Food & Nutrition Study Guide: Interrelationships between Food, Nutrition & Environment, Exams of Nursing

Download Food & Nutrition Study Guide: Interrelationships between Food, Nutrition & Environment and more Exams Nursing in PDF only on Docsity! FOOD AND NUTRITION REVISION STUDY GUIDE NOTES Topic 1 (Unit 1): Food, Nutrition, and the Environment – The Interrelationships. Learning Objectives: Part A • Define the common terms in food science and nutrition. ✓ • List the 6 classes of nutrients and their division into 2 subgroups. ✓ • Differentiate between essential, non-essential and conditionally essential nutrients. ✓ • Define calorie and recall the food energy provided by carbohydrates, protein, fat, and alcohol. ✓ • Define phytochemical, functional food, and nutraceutical, and discuss their potential role in health. ✓ Definition of Food: - “Food are vehicles for nutrients.” As said by prof. - Any solid or liquid material consumed by a living organisms that maintains life and growth. - Supplies energy and is a carrier of nutrients. - Can be processed OR raw. (Fresh pineapple is an example of raw food.) Any form of processing (e.g., packaging is considered “processed” food.) Definition of Nutrition: - Nutrients are substances the body uses for the growth, maintenance, and repair of its tissues. - The science of food, the nutrients and other substances. - Their action, interaction, and balance in relation to health and disease. - The process by which the organism (body) consumes, absorbs, transports, utilizes, and excretes of food substances. Classification of Nutrients: - Essential Nutrients : Must be obtained from food; Can get a vitamin deficiency or any disease related to a deficiency (example: anemia) or illness this way. (body cannot make this.) - Conditional Essential Nutrients : The body cannot make enough to meet the requirements for health. The body can make this, but it is not enough. - Non-Essential Nutrients: The body is able to produce these itself. (example cholesterol) Classification of Nutrients: 1. Carbohydrates 2. Lipids (Fat) 3. Proteins (all proteins contain nitrogen) 4. Vitamins ALL 1-4 ARE EXAMPLES OF ORGANIC NUTRIENTS. *O.N. means that contain Carbon. 5. Water 6. Minerals 5 AND 6 ARE INORGANIC NUTRIENTS. *IO.N. means they do not contain one of the elements of Carbon, Oxygen, and Hydrogen. For example, water has H20, but does not contain Carbon therefore it is an inorganic nutrient. Classification of Nutrients/Energy Yielding Nutrients: - Only 3 of the organic nutrients are used by the human body to produce energy. These are: ➢ Macro-Nutrients: Carbohydrates, Proteins, and Fat (Lipids.) One way to classify nutrients. These are the nutrients needed in LARGE quantities. (Grams) ➢ Micro-Nutrients: Vitamins and Minerals do NOT yield energy in the human body. However, they are involved as co-factors in various metabolic processes that convert the organic nutrients into energy. (Milligrams) ➢ Water (needed in large quantities), does NOT yield energy, but it is considered a ‘Macro- Nutrient’ Kilocalorie (Kcal) = 1000 Calories: - 1 Kcal = The heat energy required to raise the temperature of 1 kg of pure water by 1 degree Celsius. Energy from Foods: Remember This for Activity!! - The amount of energy a food provides depends on the on the content of carbohydrate, fat, and protein. ➢ Complete breakdown of a gram of carbohydrate in the body yields about 4 kcal of energy. ➢ A gram of proteins also yield 4 kcal. ➢ A gram of fat yields 9 kcal. ➢ Alcohol, though NOT a nutrient contributes to energy (7 kcal/gram) How to Calculate the Energy Available from Foods: 1. Multiply the number of grams of: Carbohydrate by 4 Protein by 4 Fat by 9 2. Add results together. For example: 1 slice of bread with 1 tablespoon of peanut butter on it contains 16 grams of carbohydrates, 7 grams of protein and 9 grams of fat. 1. Carbohydrate (16g x 4kcal/g) = 64 kcal Protein (7g x 4kcal/g) = 28 kcal Fat (9g x 9kcal/g) = 81 kcal 2. 64 kcal + 28 kcal + 81 kcal = 173 kcal ✓ How to Calculate % of kcal for Each Nutrient (in relation to total kcal from the nutrients): 1. Divide kcal of nutrition by total kcal ➢ For fat (81 x 173) 0.468) 2. Multiply result of division by 100 (0.468 x 100 = 46.8%) 3. Health Canada recommends in of NO MORE THAN 30% KCAL FROM FAT PER DAY. Functional Foods: STARRED SLIDE - Trying to consume foods believed to be rich in one or more bioactive compounds. Typically, a good source of phytochemicals. Can be plant food, or animal food. - Similar to conventional foods. (Example, yogurt, fruits) - Consumed as part of usual diet. - Demonstrated physiological benefits or abilities to reduce chronic diseases risk beyond basic foods. - Example: Regular consumption of foods containing soybean and risk of developing hypertension. - Example: Adding Saskatoon berries into plain yogurt to add antioxidants making it a ‘functional foods.’ (Don’t need to remember this though, just an example) Categories of Functional Foods: (These 2 Are Mainly ‘Whole’ Foods) 1. Basic foods (natural or processed) Ex. Fruits, Vegetables, Milk, Meat and Grains. ➢ Berries are natural foods, rich with antioxidants. (good for inflammatory conditions or cancer) ➢ Oat bran cereal is a processed food, naturally rich with beta-glucan. 2. Processed foods with added ingredients (adding vitamin D) 3. Foods enhanced to have more of a functional component. ➢ Omega-3 eggs, omega-3 milk. Nutraceuticals: Basically Pills - Products isolated or purified from food, generally sold in a medicinal form not usually associated with food and has physiological benefit or provides protection against chronic disease. - Example: Genistein (phytochemicals) from soybeans can be extracted and sold in pill form. - Example: Isoflavone activities mimic those of hormones such as estrogens and may be protective against breast cancer. Natural Health Products (NHP): *8-digit number on the label - These are not drugs; they are supplements that are extracted or synthesized from food. - Vitamin and minerals - Herbal remedies - Homeopathic medicines - Traditional medicine (chinse medicine) - Probiotic - Amino acids - Essential fatty acids Risks of Using NHP’s: STARRED SLIDE - Manufacturing problems (contamination, incorrect dosage) - Unproven claims may lead to use of the wrong product for serious conditions or to delay proper treatment. - Not enough information for people to make an informed choice (like incorrect instructions or no warnings that the product may not be suitable for certain groups.) - Interaction with prescription drugs or other NHP’s. - Unwanted side effects (allergic reactions) How Food Science is Guided by Research: Learning Objectives: Part B • Describe the scientific method (2 main kinds – 1 is to help scientist generate a hypothesis and the other 1 is meant to help scientist support or deny the hypothesis) ✓ • Differentiate between the research study designs. ✓ Food Science: - The scientific study of raw food materials, their behavior (chemical, physical, and biological), during formulation, processing, packaging, storage, and transportation and their evaluation as consumer food products. - Food science and nutritional science is different. - Food science is made up of 6 groups: ➢ Chemistry: Looking into the chemical behavior of different ingredients in food. We will be looking into the chemistry of nutrients and non- nutrients, but mainly focus on nutrients like carbohydrates, fat, and protein (energy providing nutrients). ➢ Microbiology: Deals with any microorganisms that cannot be seen by the naked eye. Will be looking into positive and negative effects of food products from farm to fork. ➢ Biology: Components of food are biological, basically looking into plants. ➢ Physics: Linked to Biology. ➢ Engineering: Industrial process involved in making food edible to humans. ➢ Nutrition: Looking into the nutritional value of food. Food Technology: - Applied agriculture (food) science to the: • Selection of raw ingredients. For example, quinoa milk as a milk alternative. There are many different types of quinoa that have different types of composition. So, how would the chemistry affect the final product? • Preservation (adding salt or sugar to preserve the food for a longer time) • Processing changing some of the chemical properties of food. • Packaging, such as waxing fruits and veggies, canning them etc. • Distribution (related to the industrial aspect of food technology) • Use (how long food will stay on the shelf) - Food needs to be safe, nutritious, wholesome food. Safety and Quality of Food: - Food science considers all safety and quality aspects of foods before it is consumed including the following aspects: • Food processing and manufacturing. • Food preservation and packaging. • Food safety and wholesomeness. • Food quality evaluation. • Food distribution. • Consumer food use and preparation. Food and Health: - Diet has always played a vital role in supporting health. - Early nutrition research focuses on identifying the nutrients in foods that would prevent such common disease as rickets (vitamin D deficiency) and scurvy (vitamin C deficiency) - Deficiencies no longer pose serious health threats. - Nutrition research is currently focused on chronic diseases associated with excess energy and nutrient intakes (CVD, obesity, diabetes, hypertension… etc.) Food Science and Nutrition Research: - Research begins with a question. “What foods or nutrients might protect against the common cold?” - In search of an answer, scientists make an educated guess called a ‘hypothesis’ (can be supported or denied, a hypothesis is NOT a fact or a theory) - Then systemically conduct research studies to test each hypothesis. The Scientific Method: - Define the problem: A question essentially. (A problem or an observation) - Formulate a hypothesis: An educated guess. Can be more than 1 hypothesis, will just have to pick the top 3 agreed upon hypothesis that you want tested. - Collect data: Test the hypothesis. - Interpret the data: Being able to describe the findings. Whether its descriptive or quantitative or both. - Generalize the findings: Once the data is interpreted you should be able to know if the hypothesis is supported or denied. Will become a ‘theory’. To generalize the theory, it must be tested at different locations in the hopes of getting the same findings. What is the Difference Between a Meta-Analysis and a Systematic Review? - Systematic review (SR): Is a comprehensive and explicit way of interrogating the medical literature. • Asking an answerable question • Identifying databases to search • Developing an explicit search strategy • Selecting titles, abstracts, and manuscripts • Abstracting dad in a standardized format - Meta-Analysis (MA): A statistical approach to combine the data derived from a systemic review. • Every MA should be based on an SR, but not every SR leads to a MA. Sometimes there isn’t much evidence to come with an MA. Learning Objectives: Part C • Describe the factors that play a role in food choices. ✓ • Define ethnocentrism and cultural relativism. ✓ • Discuss the food consumption trends that are forecast to 2020. ✓ Food Choices: - For the majority of people, the food choices made each and every day will benefit or impair their health in proportion to the wisdom of those choices. - People decide what to eat, when to eat, and even whether to eat in highly personal ways, often based on behavioral or social motives rather than on awareness of nutrition’s importance to health. Why Do We Choose Foods? 1. Personal preference: • People choose food because of taste. Most preferences are for the taste of sugar and salt. • Recent research suggests that genetics may influence people food preference. • Example: Aly doesn’t like banana’s due to the texture. • Food choices can also be caused by genetics, but more research is needed to confirm this. 2. Habit: • People sometimes select food out of habit. Eating a familiar food and not having to make any decisions can be comforting. • Example: Culture (Filipino’s eat everything with rice) • Some people can be too lazy to change their food habits. 3. Cultural/Ethnic Factors: • People eat the foods they grew up eating. Every country and every region of a country has its own typical foods and ways of combining them into meals. • Example Filipino’s with rice. 4. Social Interactions: • Most people enjoy companionship while eating. Meals are social events and the sharing of food is part of hospitality. 5. Availability, Convenience, and Economy: • People eat foods that are accessible, quick and easy to prepare and within their financial means. • Accessible, quick, and easy foods. 6. Positive and negative associations: • People tend to like foods with happy associations. Similarly, people can dislike foods that they ate when they felt sick or that were forced on them when they were not hungry. • Example, prof was forced to drink milk at a young age, at least 1 or 2 cups a day leading to a negative experience which resulted in her not liking milk. 7. Emotional comfort: • Some people eat in response to emotional stimuli, like relieving boredom, depression, or to calm anxiety. • Eating in response to emotions can easily lead to overeating and obesity but may be appropriated at times. • Can gain unnecessary weight due to this being a habit of a person. 8. Values: • Food choices may reflect people’s religious beliefs, political views, or environmental concerns. • For example, vegans not eating animal meats or products from animals, HALAL meat, or Kosher products. 9. Nutrition, body weight, and image. • Sometimes people select certain foods and supplements that they believe will improve their health and/or physical appearance and avoid those they believe may be detrimental. • Make sure to maintain a healthy body weight all the time. 10. Media advertising: • A commercial makes you hungry or kids commercials market food to kids through the use of cartoon characters. Food Beliefs: - Food beliefs, customs, attitudes, and taboos affect the diet of a given group. These beliefs determine what foods are deemed acceptable. This group would represent a country. - Example: People in Scotland eat porridge, however some British people will not, as they believe oats are for animal consumption, not for humans. In Mexico corn is a staple food, however, many Europeans believe that corn is for chickens, not people. Ethnocentrism: - “The belief that one’s own pattern of behavior are preferable to those of all other cultures.” - People tend to view their own patterns of behavior as being right, normal or best. - Newcomers coming to Canada thinking their own way of thinking/food is superior to others. Are not open to trying new foods from other countries. Cultural Relativism: - “The approach to understanding cultures in the context of the indigenous cultural groups.” - The view that no culture is superior to any other culture. - All cultural beliefs are equally valid and that truth itself is relative, depending on the cultural environment. Food Consumption Trends: - Agriculture and agri-food Canada have made predictions as to Canadian food trends that will be seen up to 2020. 1. Aging Canadians: • It is projected that there will be more seniors and fewer children in the Canadian population in 2020 then we have seen in past years. This will influence the types of food that there is demand for in the population. 2. An evolving society: • It is predicted that brand names will become less of a status symbol and will be used by consumers to express individuality. Other changes in society are also expected to affect food choices, including decreased family size, environmental awareness, globalization, and participation in work force. 3. Changing meal patterns: • Food preparation to decline, with a shift towards small, frequent meals or snacks instead of three meals a day. This would results in a greater demand for more portable food options. 4. Shifting expenditures: • It is forecast that the decline in amount of disposal income spent on food will continue to 2020. This is expected to impact the frequency that Canadians visit restaurants. • Disposable income, also known as disposable personal income (DPI), is the amount of money that households have available for spending and saving after income taxes have been accounted for. 5. Food for health: • The most significant health conditions expected to drive food choices are obesity, heart disease, and diabetes. 4. Necessary to determine end-product quality. ➢ Mouth feel (How does it feel in the mouth?) ➢ Taste the food even after packaging and after a certain time on the shelf as time may change the quality or taste of food. 5. Necessary to establish product specifications for quality assurance (QA) programs ➢ Part of quality management focuses on providing confidence that quality requirements will be fulfilled. 6. Necessary to establish shelf-life of products. ➢ How much time is needed to elapse before sensory properties change? ➢ Best before date is established. Sensory Factors: - Taste is determined by both taste buds and smell receptors. (Taste + smell are connected) - Taste buds are tiny receptor organs buried in the surface of the tongue, or in the lining of the mouth and back of throat. - All taste can be perceived EQUALLY well everywhere on the tongue. - Taste has the biggest impact on whether we choose a food. - Taste buds only recognize 5 sensations: ➢ Sweet ➢ Salty ➢ Sour ➢ Bitter ➢ Umami (refers to savory flavor, for example French fries) - All other ‘tastes’ are really smelled. Taste: STARRED SLIDE - Taste perception can vary from person to person and this may be due to genetic variations - Mouthfeel is the perception of a tactile sensations and thermal response by the epithelial lining in the mouth. Thermal mouthfeel sensations include heat (hot pepper), coolness (methanol), metallic (copper) and astringent (tea without milk or sugar) Smell: - The nose and the mouth are connected by the Olfactory Bulb (odor perception). - The combination of smell and taste is called the flavor. - Smell receptors in the nose are attached to nerves that enter the brain and report on the aroma’s (pleasant smells), odors (‘offensive’ smells) of food. - Aromas are a combination of a number of smell sensations, and the brain assembles the combination of scent signals and refers to the memory bank for interpretation. Sensory Factors: - Temperature can also influence taste and aroma and many tastes can be interactive. - Hot foods are easier to smell because only volatile molecules carry odor. When heated molecules can fly more easier in the air and can hit the Olfactory Bulb quicker. Sensory Factors: STARRED SLIDE - Texture also enters into the perception of ‘taste.’ - How food looks (color), feels (mouthfeel) and even sound (crunchy) can be a part of the taste sensations. - Tastes are perceived only when the ‘taste’ chemicals are dissolved in liquids (saliva) - Without being dissolved in saliva we will not be able to taste the food. - Dryness of the mouth will negatively affect the sensory evaluation of food. - Taste and perception of texture may cause the release of more saliva. Sensory Evaluation of Foods: - Sensory properties often determine the acceptance or rejection of foods. - Stimuli refers to triggers. - There are 6 classes of stimuli related to food: 1. Appearance 2. Odor/Aroma 3. Taste (perceived by mouth and nose) 4. Flavor (combination of aroma and taste) 5. Texture (touch or feel by mouth or tongue) 6. Sound (hear) Order of Senses: Food Perception 1. First is visual 2. Next is touch either through touch or utensils (texture) 3. Third is mouthfeel (flavor, aroma, taste) Texture Definition: - Whenever we take a food or beverage into our mouth, we perceive texture. - Texture is a measure of the physical characteristics of a food, measure as mechanical (e.g. hardness, cohesiveness, viscosity ((how thick or thin a liquid is)), adhesiveness, gumminess, springiness ((helps indicate a BBD))) - Geometrical properties , which refers to particle size and shape (smooth, gritty, chalky, grainy, lumpy) and particle size and orientation (flakey, pulpy, etc.) - Moisture properties, how wet, dry, oiliness, and moist food is. Mouthfeel Definition: - The perception of tactile sensations and thermal response by the epithelial lining in the mouth. - Therma l – Heat, coolness, metallic, astringent. - Metallic – Contamination with a metal copper. (accidentally swallowing chloride in pool) Sound: - Happens by hearing while eating. - Popping, crunching, crackling. (Example pop rocks) - Sounds indicate freshness and ripeness. Sensory Evaluation Technique (Research): 1. Subjective test methods: Results can be bias. ➢ Uses humans to measure opinion about or an ‘emotional’ reaction to a product. ➢ Measure how much you like a product (it’s acceptability) or your preference for one product over another. ➢ Less reproducible. (findings not reliable) ➢ Triangle Test: Participants are given 3 coded samples and told to choose the sample that is more different. Two of the samples are usually the same (only the researcher knows) ➢ Duo-Trio Test: One reference sample and the two test samples. Choose the test sample that matches the reference sample. ➢ Paired Comparisons: Participants are given two samples and have to choose one that has the highest attribute. (Example: Which of the two sample’s is sweeter) 2. Objective test methods: Free of personal bias. ➢ Measure the presence and/or intensity of specific attributes in the product using a ‘test equipment’ (using machines or devices to measure the attributes of food, ex: color meters) ➢ Are reproducible. (you can count on the findings) All Sensory Tests Require Controlled Conditions: STARRED SLIDE - Standardized samples (labeling, food size, etc.) - Minimized distractions - Air conditioning (flavor compounds may not be able to circulate freely) - Comfortable seating (may not perceive taste or smell properly if not seated well as it can cause a distraction to the participants) - Proper lighting (visual aspects) Hunger and The Global Environment: Learning Objectives: Part E • Define food security/insecurity, food poverty, and other hunger terms. ✓ • Discuss the 5 pillars of food security. ✓ • Discuss the reasons for hunger in developed and developing countries. ✓ • Discuss the methods of food recovery and Canadian programs that promote food security. ✓ Food: The World Perspective - The world population is over 7.5 billion. - There is enough food produced in the world to feed everybody if it could be distributed efficiently. Hunger in Developed Countries: STARRED SLIDE - It could because: • Lack of money: Having to pay for other necessities; Food is a sacrifice. • Political reasons: 80% of hungry children live in countries with surplus of food, policy makers decide who gets food. • Countries of war: Transportation is limited, other concerns beyond hunger. • Lack of transportation: Can they to a store? • Cannot afford: Prices increased vs same welfare or low income. To Stretch Meager Food Supplies – In a Household Level (Food Insecure): - Adults will often: ➢ Skip meals/cut their portions ➢ May be forced to break social rules (begging, stealing, eating garbage or dead animals) ➢ May rely on foods with low nutrient density, but high in calories. World Food Supply – According to Agriculture and Agri-Food Canada: - “About 1/3 of the global food supply is lost or wasted every year.” - “Analysis of food loss and waste in Canada, the U.S. and other developed countries shows that most of the food loss and waste occurs in households/food retail and service sectors.” - “In Canada, 6 billion kg of food was lost or wasted at the household and retail levels, representing 29.4% of the food supply in 2010.” Stats and Facts: Lamentable leftovers - Reheat, re-service, recycle: A University of Arizona study: ➢ 40% - 50% of all food ready for harvest in America, never gets eaten. ➢ 18% - 20% of US grown food are wasted because it is cheaper not to harvest it, when commodity markets plummet. ➢ 14% of the food an average American family buys, ends up in the garbage. ➢ 15% of the food purchased by the households are thrown away even though the products are still within the expiration date; some of them have not even been opened. ➢ 40% of the food in some fast food chains estimated to be thrown in the garbage. ➢ US: $590 is the average amount of dollars an American family wastes annually on food thrown in the garbage. ➢ $43 billion – Estimated amount of dollars wasted nationwide (in USA) by household food waste. ➢ 25% adverse environmental impacts, such as landfill use, soil, depletion, application of fertilizers, pesticides and herbicides, could be reduced, if national foods waste was cut in half. National Food Recovery Programs: - Trying to recover food lost to waste by re-using it differently. - Involves the collection of wholesome food for distribution to low income people who are hungry or food insecure. - 6 common methods of food recovery are: 1. Field gleaning : Collecting crops from fields that either have already been harvested or are not profitable to harvest. (They would be lower priced foods, or they can be given away for free) 2. Perishable food rescue or salvage: Collecting perishable produce from wholesalers and markets. 3. Prepared food rescue: Collecting prepared foods from commercial kitchens. 4. Non-perishable food collection: Collecting processed food from wholesalers and markets. 5. Local efforts : Food recovery programs depend on volunteers. Concerned citizens work through local agencies and Churches to feed the hungry. 6. Community-based food pantries: Provide groceries, and soup kitchens serve prepared meals. World Hunger: Causes and Outcomes – STARRED SLIDE - Quantity, quality, and availability of food (drought causing famine) - Discrimination factors that affect distribution (war, government, corruption) - Individual household’s access to available food (transportation to get food) - Access to clean water and health services. World Hunger: Causes and Outcomes - Individual childcare practices (knowledge on how to mix baby formula) - Inadequate food or nutrition intakes – causing malnutrition, weakness, and disease. (Food not having enough nutrients) - Ultimately disease conditions and malnutrition can worsen one another. This affects the life expectancy rates – in some African countries, the life expectancy averages 50 years of age. 2 Major Challenges Exist to End World Food Insecurity: 1. Provide enough for the worlds expanding population. 2. Make sure everyone has access to this food. Environmental Issues and Nutrition: Learning Objectives: Part F • Discuss factors that affect global food production and distribution. ✓ • Discuss biodiversity. ✓ • Define sustainability and discuss sustainable agriculture practices. ✓ • Discuss ways that you could positively impact the environment. ✓ Relationships Among Nutrition, Food, and the Environment: - Increased demand for food influenced by: ➢ Population growth expected to surpass food production. ➢ Urbanization: Destroying farmland and forest (affect the amount of food that is being produced) ➢ Food losses, waste, and spoilage. ➢ Demand for high animal-protein diets (plant vs animal) Increased Food Production is influenced by: STARRED SLIDE ➢ Productive land ➢ Deforestation ➢ Desertification ➢ Increased productivity ➢ Agriculture chemicals ➢ Biotechnology – Genetic engineering (discussed in Unit 4) ➢ Aquaculture (won’t be discussed extensively) ➢ Animal health ➢ Animal wastes ➢ Irrigation (discussed in Unit 4) ➢ Fuel (discussed in Unit 4) ➢ Increased exploitation of the seas ➢ Decreased food losses Environmental Problems Limiting Food Production: 1. Soil erosion and salinization (a by-product of irrigation), which result in the excessive loss of croplands. (Wearing a way of fields topsoil, by different factors and causes or forces including water, wind, farming activities which will limit crops from growing) 2. Deforestation which leads to soil erosion. Can be a result of forest fires which also leads to soil erosion which will then lead to limit food production. 3. Air pollution produced from burning of fossil fuels, which damages crops and depletes the ozone. 4. Ozone depletion, which allows harmful radiation from the sun to damage crops especially radiation-sensitive crops such as soybeans, the world’s leading protein crop. 5. Overfishing and water pollution, which are destroying fisheries and diminishing the supply of seafood. 6. Climate changes, which are caused by increased atmospheric concentrations of heat- trapping carbon dioxide produced by fossil fuels. 7. Water scarcity . In some areas there is not enough fresh water to support survival of crops, livestock and people. 8. Extensive overgrazing, which is causing deterioration of the rangelands. (Not allowing for crops to regrow) Carbohydrate Foods Include: 1. Cereal grains and flours (wheat, rye, corn rice) – Complex sugars (starches) 2. Legumes or pulses (peas, beans, lentils) - 3. Starchy roots or tubers (potatoes, yam, cassava) – Carbohydrate food/Root vegetables 4. Fruits (orange, apple, banana) – Simple sugars 5. Sugars (honey, jam, molasses) – Can be processed or natural 6. Milk products – Carbohydrates Are Classified According to the Number of Basic Sugar (saccharides) Units: 1. Mono saccharides – Simple sugars – 1 Unit 2. D isaccharides – Simple sugars – 2 Units 3. Oligo saccharides – Simple sugars – 3 to 10 Units 4. Poly saccharides – Complex sugars – 10+ Units (mostly in the hundreds) ➢ Comes in two types: 1. Digestible – Humans are able to break them down into smaller parts. 2. Fibers – Humans cannot digest this, but domestic animals, like cows can. Monosaccharides: - Includes 6 carbon hexoses and 5 carbon pentoses - Hexose sugars such as: (Only composed of 6 carbons) ➢ Glucose – The most common and most abundant sugar in nature in foods and in the human body. ➢ Mannose – Not that common in food but is used in food production. ➢ Fructose – Fruit/Honey sugar ➢ Galactose -Milk sugar and sometimes found in yogurt ➢ When the monosaccharides are linked together by condensation, we will get polysaccharides. - Pentose sugars such as: (Only composed of 5 carbons) ➢ Ribose -Non digestible ➢ Xylose – Non digestible ➢ Arabinose – Non digestible ➢ These sugars are the building blocks of fibers and gums. Glucose: 6 Carbons - Most important monosaccharide because it’s the fuel for the brain. Our body as humans cannot use any other calories coming from any other food or nutrient. - Main source of energy to keep the brain healthy. - Glucose is the most abundant sugar in the world. - Found in fruits, plants juices, and honey. - Often present with other sugars (honey with fructose) - This is the only form of sugar that circulates in the bloodstream, is it broken down in the body to give 3 products: ➢ Energy ➢ Water ➢ Carbon dioxide - Many complex carbohydrates such as starch and cellulose (fiber) have glucose as the basic unit. - Major component of corn syrup is formed by the hydrolysis of starch. - Corn syrup and crystalline glucose are widely used in the baking industry. Fructose: 5 Carbons - If found with disaccharides, fructose will give it a sweeter taste. - Found in fruits, plant juices, and honey. - Sweetest of all monosaccharides. - Very soluble and does not crystallize easily. - In the food industry, glucose is changed to fructose by addition of the enzyme called glucose isomerase. - The product is called high fructose corn syrup which is a sweetener used in soft drinks. Galactose: 6 Carbons - Not normally found in its free form in foods. - Forms a bond with glucose to produce lactose (milk sugar) - Some galactose is found in free form in fermented milk products (yogurt) where hydrolysis of lactose has occurred. - Basic unit of some complex carbohydrates such as vegetable gums. Disaccharides: - Consists of 2 monosaccharides that are chemically bonded together. - Common disaccharides in foods are: ➢ Sucrose – Fructose + Glucose (cane/beet sugar) ➢ Maltose – 2 Glucose (corn syrup) ➢ Lactose – Glucose + Galactose (milk sugar) - Disaccharides are not absorbed into the bloodstream from the small intestines and hence are not available as energy sources to the human body. - Too large to be absorbed or to be transported from the small intestines to the blood. - To be digested, Disaccharides must first be hydrolyzed to monosaccharides, which can then be absorbed into the bloodstream. - Non-hydrolyzed disaccharides pass through the small intestine to the large intestine where they are hydrolyzed by bacteria to produce acetic and lactic acids or gases. - When produced in sufficient quantities these acids have a laxative effect or even cause diarrhea. - Gas production can cause flatulence and abdominal cramps or discomfort. Hydrolysis: - Is a large molecule that is split into smaller sections by breaking a chemical bond by adding H to one section and OH to the other. - A water molecule enters the region of the functional group of a larger molecule and splits it off. Condensation: Oligosaccharides and Polysaccharides - The process by which 2 molecules are joined together to make a larger, complex molecule, with the loss of water. - Separate reactant molecules are linked together by special chemical bonds. - The reactants lost hydrogen and oxygen, which combine through a side reaction to form water. - Activated by the help of an enzyme to initiate the process of condensation. Sucrose: Glucose + Fructose - Table sugar. - Extracted from sugar cane and sugar beets. - All carbohydrates are calorie containing nutrients. (Derived from plants, except Lactose.) - Present with other sugars in fruits, honey, and vegetables. Lactose: Glucose + Galactose - Milk sugar - Only found in milk and milk products. Fiber in Health: 1. Insoluble fibers (hemicellulose provides body with roughage for poop) *Does not dissolve in water. (Example – whole grain) 2. Soluble fibers (pectin and chewing gum, best for inhibiting cholesterol absorption) *Dissolves in water, forms a gel-like solution. - A high fiber diet requires a high-water intake. - Large amount of fiber can bind materials. - Most Canadians do not consume enough fiber. (Should be consuming 20 – 25 grams/day) - Recommended daily intake: 25 – 35 grams/day ➢ Women – 25 g ➢ Men – 38 g Types of Fibers: 1. Cellulose (Homoglucans) • Consists of many glucose linked together by beta bonds to form a linear chain. • Found in cell walls of plants and are important for physical structure. • Can be chemically modified to make it more soluble and useful for thickening, gelling, and providing bulk in lose calorie products (replace fat in salad dressing) • Modified cellulose products include methyl cellulose and carboxymethyl cellulose. 2. Hemicellulose (Heteroglucans): Greatly retards stalling of bread as compared to bread with no Hemicellulose. • Also found in plant cell walls, contains a variety of different monosaccharaides building blocks (pentoses and hexoses) • Greatest effect is in baked goods where they improve the water binding of flour. • In bread dough they improve mixing quality, reduce mixing energy, did incorporation of protein, and loaf volume. 3. Beta-Glucans (Homoglucans): • Composed of glucose units that are linked together by beta bonds • Less linear than cellulose and more soluble in water. • Oats and barely are rich sources. • In the GI tract, it forms a viscous hydrated mass that traps bile acids and reduces the amount of cholesterol absorbed into the body. • Health claim for oat beta-glucans is 0.75 g beta-glucan/serving (3 servings/day) • Also decreases the rate of digestion of starch into glucose and also the rate of absorption of glucose from the GI tract into the bloodstream. • Therefore, beta-glucan may be good for diabetics as a means of controlling levels of blood sugar. 4. Pectic Substances (Pectin): • Found in both cell walls and in space between plant cells. Aids in cementing plant cells together. • Galacturonic acid (a derivative of galactose) is the basic building block of pectic substances. • Pectin is a pectic molecule common in fruits and is responsible for forming gels in various jams, jellies, and preserves. • Commercially, pectin is produced from apple cores or citrus peels. 5. Vegetable Gums/Hydrocolloids: • Long chain polysaccharides. • Various hexose and pentose sugars are the basic building blocks. • Dissolved in water, they produce a thickening or texture building effect. • Gums can help to retain water, reduce evaporation rates and modify ice crystal formation. • Widely used in the food industry: Ice cream, low calorie salad dressings, low fat foods. • Examples of gums/hydrocolloids: ➢ Seaweed extract: Agar, alginate, carrageenan. ➢ Plant seed gums: Locust bean gum, guar gum. ➢ Plant exudes: Gum Arabic, gum tragacanth. ➢ Microbial gums: xanthan gum, dextran. 6. Modified Cellulose: • Carboxymethylcellulose , which is used as a bulking agent in low calorie foods and in fruit fillings. • Methyl cellulose is used in reformed potato products and in coating and batters to reduce oil consumption. Processed and Functional Carbohydrates: Learning Objectives: • Discuss the processing of high carbohydrate foods. ✓ • Explain the process for brewing beer. ✓ • Discuss the use of carbohydrates as functional foods or nutraceuticals. ✓ High Carbohydrate Foods Are Often Processed into More Convenient Forms: - Corn: • Grounded to make cereals and tortillas. • Extracted corn starch. • Corn starch can be hydrolyzed to produce corn syrup (glucose + maltose) - Durum Wheat: Physically harder and contains more proteins than wheat. • Milled to form semolina (course flour) used to make pasta. - Wheat: Softer and not high in protein like durum wheat. • Wheat kernel is composed of; ➢ Bran (outer layer, high in vitamins, minerals, and fiber) ➢ Germ (the spouting part high in vitamins and fat) ➢ Endosperm (high in carbohydrates) (full of starch) • The bran and germ are removed during milling and the endosperm is made into flour. • Wheat is also made into cereals. Brewing of Beer: - Brewing of beer goes back over 6000 years and the methods have mostly stayed the same. - Beer is not a nutritious item, instead is a source of toxic ethanol. - Raw materials for beer manufacturing include: ➢ Cereal grains such as malted barley, rice, and corn which supply the carbohydrates (maltose and glucose) for fermentation. ➢ Saccharomyces yeast to ferment the carbohydrates into ethyl alcohol (help with fermentation/brewing process) ➢ Carbon dioxide (to purge oxygen from beer and enhance foaming) ➢ Hops (to intensify flavor and color) ➢ Water - The first step in beer making is to combine the malted barley and other cereals with water and mildly cook to produce a MASH. This process gelatinizes the starches and makes them more susceptible to fermentation. - The production of the MASH is done in steps so that the liquid portion, which is high in fermentable sugars, can be extracted. This liquid fraction is known as WORT. - The WORT is then pumped into a brew kettle and hops added. The mixture is brewed, and the hops residue is allowed to settle. - The WORT is drawn from the kettle through the bred of hops, which partially filters the WORT. - The WORT is then cooled and inoculated with yeast saccharomyces cerevisiae for fermentation. - Fermentation takes about 9 days and procedures as alcohol content of approx. 4.6% as well as some amounts of carbon dioxide. - After fermentation is complete the beer is quickly chilled and passed through filters to remove the yeast and any suspended materials. - This green beer is then stored in tanks for several months, which allows further settling of finely suspended materials and development of flavor compounds. - Additional carbon dioxide is added during storage, which also helps purge the beer of any oxygen that may be present. This is necessary because the presence of oxygen in the beer can destroy flavor and reduce shelf life. - After storage the beer is given a last fine filtration to yield a sparkling clear beverage. - The beer is bottled (known as racking) under pressure and pasteurized. Triglycerides: 1/3 Major Groups of Fats and Oils. - Approx. 95% of the fatty substances in foods fall into this group. - Composed of 3 fatty acids combined with one molecule of an alcohol called glycerol. - Fats in the diet can affect the type of triglycerides made because dietary fats are often incorporated into triglycerides in the body. - Mixed triglycerides are typical of those found in foods. The fat in a food is a mixture of many different mixed triglycerides. - Most fatty acids don’t exist in a free form but are combined in triglycerides. - Many triglycerides have different fatty acids attached to the glycerol molecule. - The fatty acids have carbon chains as short as 4 carbons and as long as 24 or more. - The number of hydrogen (H) atoms attached to the carbons in the chain can vary: ➢ Some have all the H atoms that the carbon can bond to – this results in no double bonds between carbon atoms. ➢ These types of fats are called Saturated ➢ 0 points of unsaturation = Saturated fatty acid ➢ Saturated fats (animal fat, butter) tend to be solid at room temperature. - Other fatty acids contain double bonds between some of the carbon atoms and do not gave all the H atoms that the carbon atom could bond – this types of fats are called Unsaturated. ➢ 1 or more points of Unsaturation = Unsaturated fatty acid. ➢ Unsaturated fats (canola oil, soybean oil) tend to be liquid at room temperature. Fatty Acids and Processing: Learning Objectives: Part B • Explain the difference (in structure, food sources, and on health) between saturated, unsaturated, and trans-fat. ✓ • Explain the effects of processing on unsaturated fats. ✓ Examples of Fatty Acids: - Butyric Acid: Found in butter, has 4 carbon atoms, and single bonds and is saturated. - Stearic Acid : Found in beef, has 18 carbon atoms, single bonds, and is saturated. - Palmitic Acid: Found in palm oil and cocoa butter, has 16 atoms, single bonds, and is saturated. - Oleic Acid: Found in olive oil and canola oil, has 18 carbon atoms, 1 double bond, and is unsaturated (monosaturated) - Polyunsaturated fatty acids: Contain more than 1 double bond, e.g., ➢ Linoleic Acid (Omega-6): Has 18 carbon atoms and 2 double bonds. It is found in most foods especially oilseeds such as canola and soybean. ➢ Linolenic Acid (Omega-3): Also has 18 carbon atoms but contains 3 double bonds and is found mostly in soybean, flaxseed, and hempseed. ➢ Linoleic and Linolenic Acids are essential fatty acids. The Cis-Trans Configuration: - Shape of fatty acids is changed by the presence of a double bond since the bond limits the rotation of the carbon atom. - Shape that is produced is dependent upon the configuration of the bond. - In the cis configuration, the H atoms are on the same side of the double bond. - The trans configuration, the H atoms are on the opposite sides of the double bond. - Fatty acid shape affects the melting point of the fat or triglyceride. - Trans fatty acids have a higher melting point than the cis fatty acids. ➢ The reason why it’s made is because it’s easier to store and handle. They have better physical properties than cis fatty acids. - “Why?” Because in the cis configuration, the triglyceride molecules cannot pack as closely together thus less energy is required to melt the fat. - Conversely the trans configuration allows more dense packing of the fatty acids and more energy is required to melt the fat. - Evidence suggests that trans fatty acids behave similarly to saturated fatty acids in raising level of body cholesterol and less consumption is recommended. Hydrogenation: Adding Hydrogen. - The forced addition of hydrogen atoms to the unsaturated bonds in an unsaturated fat. ➢ It raises the melting point of the fat. ➢ Used in food industry to harden liquid oils into semi-solid fats. ➢ It makes oil more resistant to oxidative rancidity. ➢ Linoleic acid becomes biologically inactive when converted to the trans form. - Trans fatty acids are formed mostly during the process of hydrogenation. - Hydrogenation of oils is carried out to: ➢ Make the oil more solid at room temperature (e.g. margarine and shortening) ➢ Increase the stability (smoke point) of these oils to thermal temperatures (frying oils) - Most margarines that currently sold are not hydrogenated but consist of careful blend of different oils and fats. - Therefore, consumption of non-hydrogenated margarine is recommended over hydrogenated type for maintaining a healthy status. Phospholipids: 2/3 Major Groups of Fats and Oils. - Present in foods in relatively small amounts but play important roles as emulsifying agents (substances that facilitate emulsion formation) - Lecithin (common emulsifier) is a phospholipid used in various foods including margarine. - Egg yolks and soybean oil are good sources of phospholipids. - Phospholipids also play a key role in the structure of cell membranes. They are typically present in foods in relatively small amounts but play important roles as emulsifying agents (substances that facilitate emulsion formation) - Emulsifiers: Are substances that keep water and fat dispersed in one another (helps them to mix together) *NOT harmful, made from plants - Lecithin: Is a phospholipid found in egg yolk. In mayonnaise, the lecithin blends the vinegar with the oil and keeps it from separating. Sterols: 3/3 Major Groups of Fats and Oils. - All together with Phospholipids, they represent less than 5% of the total of the total fats in a given food or even in the human body. - Cholesterol is probably the best-known sterol found in animal foods. - It is an essential component in the body cells but if levels get too high in the blood in can lead to heart disease and prevent normal flow of blood. - Vitamin D is also a sterol. Our bodies make cholesterol from vitamin D! - Plants do not manufacture cholesterol, but they do manufacture other sterols called Phytosterols (derived from plants) - Phytosterols are not well absorbed from the GI tract and interfere with absorption of cholesterol. - The most effective dietary measure in reducing blood cholesterol is to reduce saturated fats. - In everyday living, the best way to do this is to reduce your total fat intake. - Some types of foods such as margarine are fortified with phytosterols to help reduce the amount of cholesterol absorbed into the blood stream. Cholesterol: Linked to Saturated Fats - LDL: Low density lipoprotein. (bad) ➢ Carries cholesterol from liver to body tissues. - VLDL: Very low-density lipoprotein. (bad) ➢ Carries cholesterol and triglycerides from liver to body tissues. - HDL: High density lipoprotein. (good, cleansing agent, opposite to LDL/VLDL) ➢ Carries cholesterol back to the liver for disposal. - Factors that raise LDL and/or lower HDL should be avoided: ➢ High fat diet ➢ High saturated fat diet (exceeds 10%) ➢ Diet high in trans-fatty acids Fat Preservation and Deterioration Learning Objectives: Part C • Describe the process of fat preservation and deterioration. ✓ • Define fat replacer and discuss options for fat replacement in foods. ✓ Fat – Based Replacements: - Long chain fatty acids can be combined with sucrose to produce a compound known as sucrose polyester. - This product is neither digested nor absorbed from the GI tract (has no caloric value) but has characteristics similar to triglycerides in food preparation. - Once of such compounds approved for use in USA is known as OLESTRA and goes by the brand name of OLEAN. ➢ Olestra is NOT approved for use in Canada. ➢ Olestra has a core molecule of sucrose to which 8 fatty acids are chemically bonded. ➢ The digestive enzymes do not recognize this structure an olestra passes through the digestive system undigested. ➢ It is the most successful of the fat substitutes because it can be used in cooking or frying, and it tastes like fat. Safety Concerns: - Presence in the large intestine causes diarrhea, gas, and cramping in some people. - Can prevent absorption of fat-soluble vitamins. - May cause the loss of essential phytochemicals such as carotenes (chemicals you get from carrots that make Vitamin A) from the body. - Can contribute to different types of cancers. Functional Fats: Learning Objectives: Part D • Discuss the role of fats (such as CLA) as functional and nutraceuticals. • Differentiate between the structure of linoleic and linolenic acid and between omega-3 and omega-6 fatty acids. There Are 3 Main Types of Omega-3 Fatty Acids: - ALA (alpha-linolenic acid) ➢ From plant sources. - EPA (eicosapentaenoic acid) ➢ From fish sources. - DHA (docosahexaenoic acid) ➢ From fish sources. Potential Benefits of EPA/DHA: - Heart disease (supported by most studies) - Decrease serum triglyceride and cholesterol levels. - Protect against CVD and inflammatory diseases. - Cause relaxation of the blood vessels, resulting in lowering of blood pressure. - May slow the hardening of arteries, slowing the progression of atherosclerosis. - Infant growth and development (strong evidence) - DHA is important for normal brain development in infants. - DHA is important for normal vision development in infants. Fats and Oils as Functional Foods and Nutraceuticals 1. Omega-3 and Omega-6 fatty acids ➢ Linoleic acid (C18:2n6) is an omega-6 fatty acid. ➢ Alpha-linolenic acid (C18:3n3) is an omega-3 fatty acid. ➢ Both fatty acids have been reported to protect against cardiovascular and inflammatory diseases. ➢ It is the ration of omega-3 to omega-6 that is important. The higher the ratio the better the benefits. Can lead to adverse effects if the ratio is imbalanced. ➢ The low incidence of cardiovascular disease in Inuit population has been attributed to the omega-3/omega-6 ratio in their diet which is based principally on fish products. ➢ Fish oil contains a high omega-3/omega-6 ratio and has been shown to decrease serum triglyceride and cholesterol levels. ➢ Fish oil also lowered blood pressure in hypertensive patients. ➢ Another important food source of omega-3 fatty acid is flaxseed. ➢ Some food products that have been enriched with omega-3 fatty acids include margarines, bread, milk, orange juice, and eggs. 2. Conjugated linoleic acid (CLA) ➢ In linoleic acid, the 2 double bonds are separated by 2 single bonds. ➢ In conjugated linoleic acid, the 2 double bonds are separated by 1 single bond. ➢ CLA is a natural trans fatty acid found mostly in animal products such as milk and meat. ➢ Meat of ruminants – cows, sheeps, and other animals that chew the cud contains more CLA than non-ruminant meats such as turkey, chicken, and pork. ➢ This is because bacteria in the stomach of ruminant’s covert linoleic acid to CLA, which is absorbed into the animal tissues. ➢ Non-ruminants do not have this type of bacteria, so they cannot produce CLA. ➢ CLA is available in pills sold as over the counter products in grocery and drug stores. ➢ Has been found to suppress atherosclerosis (plaque formation that leads to heart attack) in blood vessels. ➢ Potential anti-carcinogenic effect has been shown in rats. ➢ A 2000 survey determined that women with the most CLA in their diets had a 60% reduction in the risk of breast cancer. ➢ Has been shown to reduce fat mass and preserve muscle tissue in rats. ➢ Human benefit for weight loss has not been completely demonstrated. ➢ Lowers insulin resistance which may help prevent adult onset of diabetes. ➢ Enhances immunity and resistance to infections. ➢ Important: Please consult your doctor before you take CLA. Protein and Amino Acids: Learning Objectives: Part E • Describe the synthesis and structure of protein. ✓ • Identify food sources of protein and discuss the role of protein in those foods. ✓ • Describe protein quality factors and discuss the strategy of protein complementation. ✓ Proteins: - Found in every living cell. (cells have 10 different types of protein in them) - Essential for human life and growth. - Plays several important roles in food such as water binding, gel formation, and Maillard reaction. - Specialized protein molecules called enzymes catalyze a number of important reaction in foods. - A protein is a chain of amino acids joined together by a peptide bond . Protein Structure: - Amino acids are joined by peptide bonds to produce long chains that constitute the primary structure of proteins. - Coiling of the long chain is the secondary structure . - The coils may fold back on themselves, usually in an irregular pattern to form a more compact and globular form called tertiary structure . - Some proteins have quaternary structure which occurs when globular proteins combine to form an even more complex structure. - Structure of a protein is critical to its function in a living cell or in food preparation. - 20 different amino acids are used as building blocks to form proteins - 9 amino acids are considered essential in human nutrition. - Balance of amino acids in a protein determine its biological value and nutritional quality. - Proteins with high biological value, i.e., complete proteins contain adequate amounts of essential amino acids. - Foods with high biological value proteins include animal products (i.e., milk, egg, cheese, meat and poultry) - Different plant proteins can be combined to provide diets with high biological value ➢ E.g., a mixture of legumes (beans/peas) and cereals (wheat/rice/corn) ➢ This is important in a vegetarian lifestyle. ➢ Cooking with moist heat (steaming, poaching) improves protein digestibility. - There are 2 characteristics of high-quality proteins (egg whites): ➢ Contain the essential amino acids proportional to the body’s need for them. ➢ Are digestible so that sufficient numbers of the amino acids reach the body’s cell. - Amino acids most easily digested and absorbed: ➢ Animal protein: >90% Denaturation and Coagulation: - Denaturation involves unfolding of protein structure without breakage of peptide bonds. - In most cases, denatured proteins are less soluble. If this is the case, an enzyme will lose its functional ability. - Denaturation is caused by cooking, freezing, changes in pH, salts, and mechanical action. - Continuous denaturation (unfolding) can lead to recombination of protein molecules in different ways to produce a new molecular shape. - The newly shaped molecules may bond together to form a continuous network referred to as coagulation. E.g., coagulation of egg whites when heated. Proteins Processing: Learning Objectives: Part G • Discuss the types and processing of protein foods. ✓ Animal Proteins: Protein, Carbohydrate, and Fat. - Meat: Red Meat (1) ➢ Broadly defined, meat includes muscle tissues and organs of beef, veal, lamb, pork, poultry, and fish. ➢ Red meat has a small carbohydrate content as the glycogen is used up in the continuing metabolic process after slaughter. ➢ Major components of red meat are water, fat, and protein, and some vitamins/minerals. ➢ Poultry tends to have lower fat content and slightly higher protein content per weight than red meat. ➢ High water content and neutral pH makes meat susceptible to spoilage, this can be reduced by curing (salt addition) or drying. ➢ Other processing of meat includes grinding, canning, and freezing. ➢ Meat usually has some visible fat within the muscle (white streaks of drops in the muscle) called marbling. ➢ Fat increases juiciness and gives better eating quality. ➢ Due to health concerns, some animals are to have leaner (less marbled, lower fat content) meat. ➢ The toughness of meat is directly related to the amount of collagen it contains. ➢ That is why older animals which have accumulated high levels of collagen yield tougher meat than young animals. ➢ The color of the meat is often used to judge freshness and it is usually wrapped in material that is permeable to oxygen to preserve the red color. ➢ Without oxygen, beef is normally bluish-purple. When meat is not fresh it turns brown. - Fish: White Means (1) ➢ Fish flesh is highly perishable because of the high levels of unsaturated fatty acids which can be readily oxidized. ➢ Fish fat is rich in a chemical called trimethylamine oxide (TMAO). ➢ After capture the TMAO is converted to trimethylamine (TMA) that is responsible for the ‘fishy’ odor. - Milk and Dairy products: (2) ➢ Milk is a near perfect food- it is an important source of high-quality protein, minerals, B vitamins and energy but low iron. ➢ Milk is composed of 2 protein fractions: • Casein – globular (about 80% total milk protein) • Whey – globular (about 20% total milk protein) ➢ During the manufacture of cheese, acid or chymosin/rennin (enzymes) is added to coagulate most of the casein proteins while the whey proteins remain in solution. ➢ Whey proteins are composed mostly of beta-lactoglobulin, alpha lactalbumin. ➢ Whey protein powders are available commercially as excellent sources of protein for the body. ➢ Homogenization is used to product a whole milk product and involves a process that decreases the size of fat globules dispersed in milk, so they are more optimally dispersed. ➢ Freezing destroys this process, hence the fact that when most milk products are frozen and then thawed, there is some separation of fat and liquid. ➢ Pasteurization is using heat to kill microbes in milk. (lasts 2 weeks) - Varieties of milk: (2) ➢ Evaporated milk: Over half of the water (about 60%) is evaporated out of the milk prior to canning. In Canada, it is fortified with Vitamin D and C. ➢ Sweetened condensed milk: A canned product where approx. half of the water content is evaporated out of the milk prior to canning and to which a high percentage of sugar is added. ➢ Cultured (fermented milk): Bacterial cultures added to ferment the lactose into lactic acid, which thickens the consistency. Ex. Buttermilk, kefir, acidophilus milk, sour cream, and yogurt. ➢ Skim milk powder: The water content of the milk is removed, first through the use of a vacuum and then by spray drying. This form of milk can be used in baked goods and can be added to water to reconstitute fluid milk. ➢ Ultra-high temperature (UHT) milk: The milk is heated for approx. 2-6 seconds at 300F to remove all viable microorganisms. i.e., the product is sterile. - Eggs: (3) ➢ Eggs have 2 major inner parts: while ➢ Eggs contain protein, fat, vitamins, minerals, and a small amount of CHO, with the yolk containing the fat and cholesterol and most of the calories (75%), while the white is the more protein-rich portion. ➢ Major protein of the egg white is ovalbumin. ➢ Major proteins of the yolk are the lipoproteins – high density lipoproteins (HDL) and low- density lipoproteins (LDL). ➢ The shell is 94% calcium carbonate and has small pores that allow carbon dioxide and water to escape, while allowing oxygen in. ➢ Inside the shell (rich in calcium and phosphorus) there is a shell membrane and an egg membrane both for protection. A space forms between the 2 membranes at the rounded end as the egg ages. Functional Characteristics of Eggs: 1. Emulsification: Lipoproteins and phospholipids present in the egg yolk help to keep fat dispersed in water. Used in mayonnaise, salad dressings, sauces (like hollandaise), ice cream and some cakes. 2. Foaming: Proteins in the egg whites have a high capacity to form strong protein films that surrounds air bubbles to produce stable foams. Used in souffles, fluffy omelets, meringues, and some cakes (e.g., angel food) – adds texture to foods. 3. Coagulation: Egg white proteins can set and form a gel during heating. They can help to bind food mixtures together, such as meat loaf, meat patties and manicotti. (coagulation works after heat is applied) Plant Proteins: - Plant proteins are divided based on solubility: A. Albumins – Soluble in water B. Globulins – Soluble in salt solutions but insoluble in water. C. Gliadins – Soluble in 70% - 90% alcohol (sanitize solution) D. Glutelin’s – Insoluble in neutral aqueous solutions, saline solutions or alcohol. Can only be solubilized by diluted alkaline solutions. Plant Protein Crops: 1. Cereals: Have protein contents no greater than 15%-17%. E.g., wheat, corn, rye, rice, oats, and barley. ➢ Wheat: Principal proteins are the gliadin and glutelin fractions, which represent about 80% of the endosperm protein. (gliadin + glutelin = gluten) ➢ Gluten is a complex formed from gliadins and glutelin’s following hydration and mixing of wheat flour. (insoluble fibers, found in wheat, rye, and barely. Responsible for the elastic consistency of dough and the chewiness of foods made from wheat flour.) ➢ The hydrated gluten complex forms a 3-D viscoelastic network that gives wheat flour its valued dough and bread-making characteristics. ➢ 2. Pulses, nuts, and oilseed (legume) storage proteins. ➢ Pulses are beans (e.g., navy beans, kidney beans, black beans, etc.), peas (e.g., split peas and chickpeas) and lentils. ➢ High protein content (18% - 45%), majority of the proteins are albumins and globulins. E.g. peas, lentils, beans, soybean, canola, and mustard. ➢ Very little gliadin and glutelin. ➢ Most pulses offer protein of good quality, while being low in fat. ➢ Legumes include pulses, soybeans (high source of protein), seeds, and peanuts. ➢ Nuts are grown on various trees and ground plants. Provide protein, unsaturated fat, fiber, vitamins, minerals and phytochemicals. - Minerals are indestructible due to their inorganic nature (not compounds, they are 1 element – more stable in foods) - Minerals are heat stable and can impact the chemical and physical properties of foods (not sensitive) - Does NOT need to be handled with the special care that vitamins require. Topic 4 (Unit 4): Food Production and Preservation Food Production and Preservation History: - Agriculture revolution – 12,000 BC: ➢ Planting and harvesting of crops. ➢ Domestication of animals and plants (> security of food supple) ➢ Salting – As a method of preservation was mastered in Europe approx. 500 BC and salt became a major commodity. - Fertile Crescent: ➢ The fertile crescent gave birth to agriculture. ➢ Region contained unusually fertile soil and productive fresh water. ➢ Was home to the 8 Neolithic founder, crops important in early agriculture: Wheat, einkorn, barley, flax, chickpea, pea, lentil, bitter vetch. - Late 15th century – The first wheat was introduced in Canada. - Industrial revolution – 18th and 19th Centuries: ➢ Technological change – Modern production processing and distribution systems. ➢ Transportation of foods a priority. ➢ Refrigeration and drying developed in the 19th century. ➢ Canning methods developed in the 1780’s. ➢ Pasteurization. - Science Revolution – 20th Century: ➢ Biotechnology. ➢ Decrease in biodiversity began with the ‘Green Revolution’ – The dramatic increase in food production in the 1960’s due to new seeds developed from crossbreeding. ➢ Planting of high yield wheat varieties: • High yields monoculture > fertilizers > pesticides > irrigation Learning Objectives: • Define the common terms in food production and food preservation that is listed in the course notes. ✓ • Discuss the 4 methods of increasing food production. ✓ Food Production: Four Methods of Increasing Food Productivity 1. Agricultural chemicals: ➢ Fertilizers and pesticides increase crop yield and quality when applied appropriately. ➢ Indiscriminate use can contaminate the water we drink and the plants and animals we eat. 2. Aquaculture (fish-farming): ➢ Practice of mass production of fish in ponds or in floating cages in rivers, lakes, or the sea. (Enabling the fishes to reproduce) ➢ Food safety concerns: • Chemical pollution and oil spills, • Residual levels of drugs in flesh, drugs are used to prevent diseases in such dense populations. (can result in fish waste and would spread different kinds of diseases within the population) 3. Irrigation: STARRED SLIDE ➢ Involves providing water to crops. ➢ Helps provide a wide variety of food that would otherwise be less available. ➢ Food safety concerns: • Higher salt in soil. • Cost of fuel to pump will increase. • Spread diseases (30+ diseases have been linked to irrigation projects and dams in tropical countries) 4. Food Biotechnology: ➢ Genetic engineering: Manipulation of the genetic material of living organisms (virus, bacteria, plants, animals, humans) ➢ Synthesizing a gene from one organism and putting it into a different organism’s gene to create a new biological products (increasing crop size, foods, etc.) ➢ Biotechnology is the practice of genetic engineering to make useful biological products. ➢ Genetic engineering has been used to: • Improve resistance of food crops to pest infestation. • Increase crop yield. • Extend shelf life. • Improve food texture/taste. • Improve quality attributes. • Enhance nutritional content. (‘super’ foods) • Increase yield from animals (i.e., milk production) • Improve health of animals. • Enhance quality of product derived. ➢ Sometimes it’s difficult to tell the difference. ➢ Genetic modification accepted for medication, but NOT for food. ➢ People have moral and cultural reactions with food. ➢ Seedless are not GMO, they are hybrids. Hybrids are ok because they are not altering the gene. Genetic Engineering: - Only the desired gene is transferred to the new variety. Learning Objectives: • Discuss the use of genetic engineering in animal plant products. ✓ • Discuss the benefits and concerns with food technology. ✓ Traditional Breeding: - The desired gene is not the only gene that is transferred during crossbreeding. Typical Examples of Genetic Engineering: - Delayed ripening in tomato fruits. - Chymosin or rennin (an enzyme) used for cheese making. - Round-up technology that confers herbicide resistance on certain crops like canola and soybean. - Bovine somatotropin hormone (BST). Also called bovine growth hormone. Improves milk production in cows by 10% - 14%. BST is not approved in Canada. - Plant and animals modified by genetic engineering are called transgenic. - Corn, soybean, and canola being altered to increase the % of more desirable unsaturated (problem with unsaturated fat – they have double bonds and whenever there’s oxygen in the food packets, it’s going to breakdown the bonds, resulting in rancidity) - Potatoes with modified starch content to absorb less fat during frying. - Rice with increased % of lysine (an essential amino acid) to reduce childhood blindness. - Poultry producing eggs with increase % of lysozyme. - Corn with increased % of protein for animal feed. - Increased gluten content of wheat and barley flours. - Plants developed to have increased resistance to frost. - Lactoferrin (essential form of iron) found in human milk being introduced to cow’s milk. - Golden rice: ➢ PSY (phytoene synthase) from daffodil (narcissus pseudonarcissus) ➢ CRTL (phytoene desaturase) from the soil bacterium Erwinia Uredovora. What Does the Biotechnology Industry Say? - Genetic engineering is an extension of plant breeding techniques. - Genetically engineered foods are not nutritionally different from conventional foods. - The potential for benefits is immense, especially with improving agriculture practices. Food Processing: - Conversion of raw plant and animal tissue into convenient and practical forms for consumption. - The basic principles of food processing to achieve preservation include: ➢ Moisture removal: Removing biologically active water in an attempt to stop microorganism growth. E.g., drying dehydrating can help remove the moisture. ➢ Heat treatment: E.g., pasteurization, bleaching, canning, baking, cooking, sterilization. ➢ Low-temperature treatment: Cold storage e.g., refrigeration, freezing the moisture. ➢ Acidity control: Controlling the pH of the food e.g., by adding an acidulant. ➢ Traditional non-thermal processing: Through chemical additives (preservatives) or food packaging. ➢ Non-thermal processing innovations: E.g., irradiation, high pressure. ➢ Food processing aids: Specific food additives like gums, natural coloring agents, enzymes, and sweeteners. Food Preservation: - The use of specific processing techniques to reduce spoilage microorganisms (loves water, high protein foods, and less acidic conditions) in food to improve safety and shelf life . - Foods spoil (rancidity) because of microbiological (E. coli, salmonella), chemical, physical, or enzyme-induced (color changing, like apples browning, NOT detrimental to health) decay. - Decrease in food losses is achieved mainly by food preservation and food additives . - Biologically active water in tissues is one of the primary cause of food spoilage. - Foods with a high aw deteriorate quickly, whereas foods with low aw can be stored for extended periods. ➢ aw = P/P0 ➢ P = Vapor pressure in food (number less than 1) ➢ P0 = Vapor pressure of pure water (high than 1) Water Activity (aw) of Common Foods: - The higher the water activity (more than 1), increases the spoilage that can happen to that food because bacteria has access to more water. - Same water content does not mean same water activity. - 2 highest water activity: ➢ Fresh meat and fish: 0.99 ➢ Raw vegetables (carrots, cauliflower, peppers): 0.99 - 2 lowest water activity: ➢ Dried fruits: 0.60 – 0.65 ➢ Dried spices and milk powder: 0.20 – 0.60 Food Preservation: - Other Major causes of spoilage: ➢ (1) Biological changes: Growth of microorganisms ➢ (2) Chemical changes: Oxidation or enzyme reactions ➢ (3) Physical changes: Separation of water and oil that can occur in foods like mayonnaise/ yogurt as they age. - The 3 main classes of food preservation: ➢ (1) Chemical: Addition of sugar, salt, or chemical preservatives. (control biological/chemical spoilage) ➢ (2) Biological: Fermentation (good microorganisms/enzymes – no additional of chemicals) ➢ (3) Physical: Drying, heating, cooling, irradiation. Chemical Preservation: 1/3 - Addition of sugar, salt, or chemical preservatives to reduce spoilage. (sugar and salt suck the moisture out) - Salt and other preservatives such as potassium sorbate, lower the aw in foods. - Preservatives: Additives that maintain the freshness of a food. Biological Preservation: 2/3 - Fermentation: A preservation technique that involves bacteria or yeast acting on the carbohydrates of a food. - Fermentation lowers the pH of the food product, resulting in taste changes. - Encourages the growth of friendly bacteria, which in turn inhibit the growth of pathogenic bacteria. - Sale of vinegar may be added to control bacterial growth during fermentation. - Examples of fermentation: ➢ Cucumbers are fermented and stored as pickles. ➢ Cabbage is fermented to produce products like sauerkraut or kimchi. ➢ Milk undergoes fermentation to become cheese, yogurt, sour cream, and buttermilk. Microorganisms: - Good (food preservations, health) - Bad (harmful; health and spoilage, toxins) - Neutral - Doesn’t like acid. Physical Preservation: 3/3 - ‘Controlling temperature or the moisture content by physical/mechanical means’ - Drying (getting rid of moisture or water content) ➢ Involves the removal of water from food. ➢ The food is preserved because microorganisms cannot survive in a dry environment. ➢ In ancient times, drying was done predominantly by the sun (issues: slow, insects, weather) ➢ Currently the food industry uses oven/plate drying, spray drying, drum drying, and freeze drying. ➢ 2 problems with drying by heat: 1. Loss of heat-sensitive nutrients such as vitamin C, riboflavin, and niacin. 2. Can alter sensory properties (color, flavor, texture) - Thermal processing (applying heat) ➢ The important heat treatment methods used in processing include: • Sterilization • Pasteurization • Blanching • Canning ➢ Thermal processing can cause a loss of heat-sensitive nutrients. - Cooling (use of cold temperatures) - Irradiation (using rays to control the growth and multiplication of the microorganism) Oven/Plate Drying: - Food spread on slatted floor or on shelves inside kilns or drying rooms. - Hot air is then blown over and through the food. - Alternatively, food can be placed on trays that travel through a tunnel of hot air (e.g., slices of fruits are placed on conveyer belts that are hot) - The high temperature removes the moisture from the food and often the moisture is removed from the air by creating a vacuum environment. Drum Drying: - Food is evaporated, the concentrated products is then poured over large heated drums that keep rotating and get coated with more and more food product. The thin layer of the food product on the heated drum dries very quickly into thin layers. These layers are further ground to obtain powders. - Used for mashed potato flakes, quick cooking hot cereals. - Home canning: 1. Boiling water processing ➢ Used for fruits and vegetables with pH below 4.6 ➢ Jars are placed in canner filled with enough water to come 2 inches up the outside of the jar. ➢ The water is then heated, and the jars are boiled. ➢ The time needed depended on the type of food being canned. 2. Pressure canning ➢ Used for meats, fish, poultry and vegetables with a pH higher than 4.6 ➢ The jars are placed in a pressure canner with water and then heated. The time needed depends on the type of food being canned. ➢ Low canning temperatures and improper seals may allow growth of Clostridium Botulinum which causes the deadly botulism poisoning. ➢ Cannot survive in acidic environments so boiling is sufficient to process foods with a low pH ➢ Foods with a higher pH need to be canned under pressure so that the temperature can reach above 116 degrees to kill Clostridium Botulinum spores. - Method chosen depends on the pH of the food to be canned. Cooling: Refrigeration: - Involves cooling of food temperatures to levels that slows down the growth of microorganisms. - Excellent for maintaining the sensory qualities and nutritive value of foods. - Refrigeration slows down food spoilage. - Some organisms, such as listeria can grow at refrigeration temperatures. - Refrigeration does not prevent the growth of molds. ➢ Ideal refrigeration temperature: 4 degrees Celsius ➢ Ideal freezing temperature: -18 to -22 degrees Celsius Freezing: - Involves cooling of food temperature levels prevent growth of microbes because it makes water unavailable to the microorganisms. - Prevents the growth of microorganisms, but enzymes can still be active and spoil foods. - Some oxygen still available; food cannot be frozen indefinitely. ➢ Freezer burn – Water loss in food by sublimation. (Food was not packaged properly) ➢ Occurs when water evaporation from the frozen food goes into the air spaces in the package and ice crystals form. ➢ The food develops white or greyish colored patches that, when thawed may have a sponge-like texture. ➢ Although its less appealing, freezer burned food is safe for human consumption. - When meat is thawed, some vitamins and minerals may be lost in the drippings. Irradiation: - Most innovative. - Radiation is applied to the food, typically food would be packaged before you would apply the radiation using different types of radiation. This changes the chemistry within the food particles and can also change the biology of the microbes to control their growth. - Sterilization treatment of food with a type of radiation energy known as ionizing radiation . - 3 different types of radiation are allowed: ➢ Gamma rays ➢ X-rays ➢ Electron beam radiation. - “Cold pasteurization” Why Use Irradiation? - Kills molds, parasites, insects, and harmful bacteria. - Slows ripening or sprouting process (e.g., onions, potatoes) - Can be used on frozen/fresh foods and dehydrated foods such as seasonings, cereals, and flours. - Can’t be used on soft foods like tomatoes because it makes the skin ‘mushy’ Irradiated Foods: - All irradiated foods must carry an international symbol called the ‘Radura.’ The symbol must be accompanied by the words ‘treated by irradiation’ or ‘treated by ionizing energy.’ ➢ The symbols come in different colors and the colors indicate the level of radiation. - In Canada only 4 types of food products have been approved for irradiation: ➢ Potatoes ➢ Onions ➢ Wheat, flour, and whole-wheat flour ➢ Dehydrated seasonings/ whole or ground spices ➢ Fresh/frozen meat or raw ground beef Why is Irradiation Not Used More? - Each year, millions of people could be spared if irradiation was used. - Raw poultry, when irradiated is 99.9% free of harmful microorganisms. - It isn’t used as much because: ➢ Consumer acceptance (people thinking it is associated with cancer) ➢ More expensive Safety of Irradiation: - 50+ years of animal research has revealed no toxic effects from irradiated foods. (No guarantee for safety regarding human consumption though) - Risk to employees in irradiation plant: Measures in place to minimizes safety risks. - Concerns for the safe transportation of radioactive materials needed for irradiating foods and the disposal of radiation active waste. Effects of Irradiation on Nutrition and Quality: - Water: Off-odors and off-flavors (hydroxyl radicals) - Lipids: Rancidity of the fat. - Proteins: Not compromised. - Carbohydrates: Some structural properties such as gelling may be reduced. - Vitamins: Vitamins A, E, C and Thiamin are sensitive to breakdown with irradiation, especially when higher doses are used and when foods are used and when foods are packaged with air in the package. - Physical properties: When high levels of irradiation are used, changes in texture, color, and flavor can occur. (e.g., tomatoes can become soft/mushy) Newer Technologies in Food Preservation: - High-hydro plastic pressure processing or ultra-high pressure (UHP) processing. ➢ Food is placed under uniform pressure of up to 100,000 lbs. per square inch. ➢ Living microbes are destroyed by anything greater than 60,000 pounds per square inch. ➢ Works well on acidic foods such as yogurt and fruit. ➢ Pressure assisted thermal sterilization (PATS) is known to kill Clostridium Botulinum, but PATS will destroy a lot of the nutrients and change the quality of the food a lot. (Still under further development. - Non-thermal: UV radiation, pulsed light, and ultrasound. - Continuous microwave process: Food is passed through a tube and the microwaves are directed towards the center of the food. This leads to heating the food from the inside out. - Antimicrobial chemicals: ➢ Can be sprayed onto foods or foods can be dipped into the antimicrobial solution. ➢ Many natural chemicals exist that can inhibit microorganisms. ➢ Acetic, benzoic, and sorbic acids. Food Packaging: Learning Objectives: • Discuss the purpose of food packaging and describe the types of food packing. ✓ • Discuss the environment impact of food processing and packaging. ✓ Food Packaging: - Main purpose: To slow food deterioration by offering protection from physical, chemical, and biological factors. - Common food packaging materials include glass, paper, plastic, (thermoplastic) and metal - The type of packaging used is often dependent on the food to be packaged. For example, foods containing moisture, cannot use paper to wrap the food, only plastic. Health Canada: Sets Standards and Regulations - Food safety policy - Standards setting - Risk assessment - Analytical testing research audit Canadian Food Inspection Agency (CFIA): Ensures Standards are Met - Created in 1997, reports to the Minister of Agriculture and Agri-Food. - Provides all inspection services related to: ➢ Food safety ➢ Economic fraud ➢ Trade related requirements ➢ Plant and animal health programs - Follows your food from farm to fork to ensure each and every step is done properly to prevent contamination of food from biological and chemical hazards. - Specific Duties and Roles: 1. Controlling animal diseases and pests: • Stop diseases and pests from entering Canada. • Control or eradicate diseases if they do occur. • Inspect farmers’ field and imported plants. • Able to quarantine animals. 2. Inspect Foods: • Register and inspect all food processing plants. • Monitor imported foods. • Coordinate the food recall program. • Test foods for chemical residue. 3. Preventing Fraud: • Enforce labeling laws (details on food labels. ex, food is irradiated but it’s not shown on the label, no secret ingredients). • Check quantities, verify composition, and grade. 4. Regulate seed, feed, and fertilizers: ➢ Protects Canadians from unfair production practices. 5. Diagnostic problems: ➢ Identify problems in food products. ➢ Develop rapid methods for detecting food pathogens (disease causing microorganisms). 6. Enforcing safety standards: ➢ Work with provincial and municipal inspectors. ➢ Respond to security threats. ➢ Food recall enforce safety standards. The Safe Food for Canadians Acts: - Makes food as safe as possible for Canadian families; - Protects consumers by targeting unsafe practices; - Implements tougher penalties for activities that put health and safety at risk; - Provides better control over imports; - Institutes a more consistent inspection regime across all food commodities; and - Strengthens food traceability. Food Poisoning: Learning Objectives: • Define food borne illness and discuss the incidence and general symptoms. ✓ • Identify the population groups at greater risk for food borne illnesses. ✓ • Identify 3 types of hazards that are associated with food borne illnesses. ✓ • Differentiate between food infection and food intoxication. ✓ • Discuss the requirements of microorganisms for growth and how growth can be controlled. ✓ • For the 4-common food poisoning bacteria discussed in the notes, describe the basic characteristics of the bacteria where the bacterium is found, common foods contaminated, time of onset, common symptoms, duration of symptoms, and prevention. ✓ Microbial Food Poisoning (Food-Borne Illness): - An illness transmitted to humans through food or water. - About 4 million cases every year in Canada. For every reported case, hundreds of cases go unreported. ➢ 77% of cases occur in food service establishments ➢ 20% of cases occur in the home ➢ 3% of cases occur in food poisoning Sources of Contamination: - Environment - Agriculture - Animal husbandry (Animal husbandry is the branch of agriculture concerned with animals that are raised for meat, fiber, milk, eggs, or other products. It includes day- to- day care, selective breeding and the raising of livestock) - Processing - Packaging - Storage - Meal preparation (food handling – where the most contamination happens) - Other sources of contaminations: 1. Physical hazards (hair, metal, broken glass, jewelry, stones, etc. – can cause internal cuts, but the body should pass them, depending on the size and where the piece goes) 2. Chemical hazards (sanitizer/bleaching solutions, pesticides/antibiotics, lubricant/paint, excess food additives, natural toxins) 3. Biological hazards (bacteria, mold, viruses, parasite) ➢ Associated with the greatest number of cases of food borne illnesses and death. Food-Borne Illness Can Be Caused by Infection or Intoxication: 1. Infection: Happens when you eat (consume) the pathogen. The pathogen will begin to multiply rapidly and infect tissues in the body. ➢ Bacteria multiply and infect tissues (e.g., the intestinal tract causing damage to the epithelial cell lining) ➢ Imbalance of osmotic pressure occurs, resulting in diarrhea, damaged cells in intestinal tract signal the brain to trigger vomiting, and fever occurs) ➢ Onset (beginning) of symptoms takes 12 hours to 2 days on average (e.g., salmonella, shigella) 2. Intoxication: The bacteria produces the toxins; Causes no harm to tissues as they multiply. ➢ Bacteria produce toxins in the food or in the body as they multiply, toxins grow if food us not stored properly. ➢ Toxins can cause damage to the cells that line the intestinal tract and can travel to the kidneys and cause damage. ➢ Onset of symptoms takes a few hours; very fast (e.g., staphylococcus aureus, clostridium botulinum) • Bakery products (chocolate eclairs, milk or milk products) ➢ Prevention: • Do not allow infected persons to prepare food; • thorough heating and cooling of food; • Good sanitation 3. Escherichia Coli 0157:H7: ➢ A relatively new strain of E. Coli ➢ Onset is 12 – 18 hours (up to 8 days), duration 2 – 9 days. ➢ Typical symptoms include nausea, vomiting, watery, and bloody diarrhea, abdominal pain, and dehydration. ➢ Severe cases: Headache, muscle cramping and temporary changes in blood pressure and pulse rate may occur. ➢ 2% - 7% of cases lead to hemolytic uremic syndrome which can lead to kidney failure. ➢ Typical foods: • Raw or undercooked meat • Raw milk/unpasteurized fruit juices. ➢ Known as the hamburger disease ➢ Prevention: • Cook meat thoroughly, especially ground meat. • Pasteurize milk and fruit juices. • Avoid cross contamination. 4. Clostridium Botulinum: Toxin ➢ Anerobic (doesn’t require oxygen) bacteria present in soil, water, plants, intestinal tract of animals/fish. ➢ Produces the most powerful natural toxin that blocks nerve function. ➢ Typical foods: • Found in improperly home canned of commercially canned foods (leaky, building, dented, and broken cans). • Especially lowkey acid home canned foods (vegetables). ➢ Onset of symptoms: 12 – 72 hours. ➢ Double vision, inability to swallow, speech difficulty, and progressive paralysis. ➢ Long-term complications: Fatigue, shortness of breath (antitoxin) ➢ Prevention: Sterilize canned foods, cook/reheat food properly (spores are killed at 120 degrees Celsius). Cross Contamination: - Cross contamination is the transfer of bacteria from one food to another, or from a surface to a food (or vice versa) - An example of this would be cutting raw chicken on a cutting board and then using the same knife and cutting board to cut lettuce without cleaning it properly in between. Food Safety: Learning Objectives: • Discuss what HACCP is and the 3 reasons it was developed. ✓ • Discuss the 7 principles of HACCP. ✓ Hazard Analysis Critical Control Points (HACCP): - Initially developed in the USA to ensure safety of foods to be used in the space program. - It is a preventative system that significantly reduces production of unsafe food products. - It is food safety protocol that food processers and manufacturers follow involving: ➢ The manufacturing environment ➢ Food handling personnel ➢ Equipment ➢ Food itself - Based on risk assessment and the identification of critical control points (points during food production process that need to be controlled to ensure safety of the food product). - HACCAP was designed for 3 reasons: 1. Identify hazards that could occur to foods during their preparation. 2. Identify control steps in food production that ensure a safe product 3. Monitor these steps to ensure they are being controlled. HACCP System Consists of 7 Principles: 1. Conduct a hazard analysis. 2. Determine critical control points. 3. Establish critical limits. 4. Establish monitoring procedures. 5. Establish corrective actions. 6. Establish verification procedures. 7. Establish record-keeping and documentation procedures. Steps to Food Safety: 1. Shopping: ➢ Shop last during outing. ➢ In the grocery store, buy perishable items last. Don’t leave perishable foods for long periods without adequate storage. ➢ Pack a cooler in your car. (for frozen foods if you can’t go home directly after grocery shopping) ➢ Don’t buy if you won’t use before the expiry date. (best before date relates to the quality of the food, not when the food spoils) ➢ Buy foods in good condition (color of food, any dents in the can?) 2. Storage: ➢ Refrigerate temperature no higher than 4 degrees Celsius. ➢ Freeze temperature no higher than -18 degrees Celsius. ➢ Freeze meat if you cannot use it within a couple of days. ➢ Prevent raw juices of meat from dripping on other food. (separate meat and veggies) ➢ Don’t store foods for too long. 3. Preparation: ➢ Use good quality ingredients (e.g., not expired pasteurized milk and juices, etc.) ➢ Use sanitary equipment. ➢ Clean counter tops prior to food preparation. ➢ Ensure cutting boards and knives are clean. (different cutting boards and knives) ➢ Wash hands with soap and water before preparing food. ➢ Replace dish cloths, towels, and sponges often. ➢ Avoid cross -contamination. ➢ Use plastic cutting boards. ➢ Rinse cutting boards with sanitizing solution to prevent the growth of food spoilage microorganism. ➢ Wash raw produce prior to use. ➢ Thaw foods safely. • Under cool running water. • In a microwave oven followed by immediate cooking. • In a refrigerator until used, temperature never above 5 degrees Celsius. • As part of the cooking process. ➢ Cook poultry, ground meat, fish, eggs thoroughly. (internal temperature must reach 74 degrees Celsius) ➢ Use a meat thermometer. ➢ Keep foods out of the danger zone: • Keep cold foods below 4 degrees Celsius. • Keep hot foods above 64 degrees Celsius. ➢ When using a microwave – cover, rotate, and stir. 4. Serving: ➢ Use clean dishes. ➢ Never place cooked food on a surface that has held raw meats, fish or poultry to prevent cross-contamination. ➢ Never leave perishable foods out of refrigerator for more than 2 hours. ➢ **BACTERIA WILL DOUBLE EVERY 20 MINUTES** Handling of Leftovers: ➢ Refrigerate promptly (several small shallow dishes if necessary) ➢ Remove stuffing, store separately. ➢ Re-heat foods adequately. (Heat food back to 74 degrees Celsius) ➢ Discard foods with past expiry dates. ➢ If in doubt throw food away.