(Chapter 13) How Safe Is Our Food Supply?

(3) CONCEPT CHECK - Agricultural and Industrial Chemicals in Food: 1. How can a pesticide used on broccoli plants end up in milk? 2. How can organic food cause food-borne illness? 3. What can you do to minimize PCBs in your diet?

1. By bioaccumulation. When a cow eats a contaminated broccoli plants and excretes its contaminated milk. Pesticides can travel into water supplies, soil, and other parts of the environment. Because pesticides enter the environment, pesticide residues are found not only on the treated plants but also in meat, poultry, fish, and dairy products. 2. They are not completely free of synthetic pesticides and other agricultural chemicals not approved for organic use because irrigation water, rain, and a variety of other sources can introduce trace amounts into organically grown foods. The threshold for pesticide residues in organic foods is set at 5% of the EPA's pesticide-residue tolerance. Choosing organic food will reduce pesticide exposure, but it will not make your food risk free. 3. Avoid certain types of fish and limit consumption of others. Make sure your food was checked for PCBs and check with your local health department for recommendations regarding fish consumption.

(1) CONCEPT CHECK - Keeping Food Safe: 1. What causes food-borne illness? 2. Why might the same food make one person sick and not another person? 3. Who is responsible for the safety of the food you eat? 4. How does HACCP differ from traditional visual food inspection?

1. Caused by eating food that has bacteria, viruses, and fungi (microbes). 2. It will depend on their overall health, nutritional status, and immune system. 3. Agencies at international, federal, state, and local levels monitor the safety of the food supply (government). Food Manufacturers and Retailers with a Hazard Analysis Critical Control Point (HACCP) and consumers. Most cases consumers are responsible. 4. Traditional methods of protecting the food supply, which use visual spot checks and random testing to catch contamination after it occurs, HACCP systems are designed to prevent contamination. Where as a HACCP system analyzes food production, processing, and transport, with the goal of identifying potential sources of contamination and points where measures can be taken to control contamination.

(1) LEARNING OBJECTIVES - Keeping Food Safe: 1. Name the primary cause of food-borne illness. 2. Explain why a contaminated food does not cause illness in everyone who eats it. 3. Discuss the roles of the federal agencies responsible for the safety of the U.S. food supply. 4. Explain how a HACCP system helps prevent food-bone illness.

1. Contaminated foods y microbes; occasionally it is caused by toxic chemicals or other contaminants that find their way into food. 2. Whether or not you get sick from eating a contaminated food depends on how potent the contaminant is, how much of it you consume, and how often you consume it, as well as on your age, size, and health. Some can have a good immune system, others don't absorb the contaminants. An individual's size, overall health and nutritional status, an immune function affect his or her risk of food-borne illness. 3. Federal agencies set standards and establish regulations for the safe handling of food and water and for the information included on food labels. They regulate the use of additives, packaging materials, and agricultural chemicals; inspect food processing and storage facilities; monitor domestic and imported foods for contamination; and investigate outbreaks of food-borne illness. 4. a) conduct a hazard analysis b) identify the critical control points c) establish critical limits d) establish monitoring procedure e) establish corrective action f) keep records g) verify procedure

(4) LEARNING OBJECTIVES - Technology for Keeping Food Safe: 1. Describe how temperature is used to prevent food spoilage. 2. Discuss how irradiation preserves food. 3. Explain how packaging protects food. 4. Discuss the risks and benefits of food additives.

1. Cooking kills disease-causing organisms and destroys most toxins. Lowering the temperature of food by means of refrigeration or freezing does not kill microbes but preserves the food and protects consumers because it slows or stops microbial growth. 2. Irradiation exposes food to high doses of X-rays, gamma radiation, or high-energy electrons in order to kill microbes and insects and inactivate enzymes that cause germination and ripening of fruits and vegetables. Irradiation is a process that exposes foods to radiation in order to kill contaminating organisms and retard the ripening and spoilage of fruits and vegetables. 3. Modified Atmosphere Packaging (MAP): It keeps molds and bacteria out, keeps moisture in, and protects food from physical damage. Oxygen is taken out to prevent from the growth of aerobic bacteria, slows the ripening of fruits and vegetables, and sows down oxidation reactions, which cause discoloration in fruits and vegetables and rancidity in fats. 4. Risks that some individuals are allergic or sensitive to certain food additives. Benefits used to make food safer; maintain palatability and wholesomeness; improve color; flavor; or texture; aid in processing; and enhance nutritional value. Their use ensures the availability of wholesome, appetizing, and affordable foods that meet consumer demands throughout the year.

(2) CONCEPT CHECK - Pathogens in Food: 1. How does Clostridium botulinum cause food-borne illness? 2. What pathogenic bacteria commonly contaminate chicken and eggs? 3. How do viruses make us sick? 4. How does refrigeration help prevent food-borne illness?

1. Deadliest of all bacterial food toxin. Have heat-resistant spores and produces toxins when they begin to grow and develop. When consumed, the toxin blocks nerve function, resulting in vomiting, abdominal pain, double vision, and paralysis that leads to respiratory failure. You get ill from the toxin if your body absorbs it in gastrointestinal tracts and it enters the blood stream. Infants are more likely to get it due to not enough intestinal bacteria to kill the toxin. 2. Salmonella and campylobacter 3. Viruses make us sick by turning our cells into virus-producing factories. They cannot live on its own, they have to invade a cell to replicate itself. It doesn't have any cell organs. 4. Storing food at refrigerator or freezer temperatures either limits or stops microbial growth. The temerature range that is most favorable for microbial growth is the range at which food usually sits between service and storage (room temperature).

(5) LEARNING OBJECTIVES - Biotechnology: 1. Explain how genetic engineering introduces new traits into plants. 2. List ways in which genetic engineering is being used to enhance the food supply. 3. Discuss some potential risks associated with genetic engineering. 4. Describe how genetically modified foods and crops are regulated to ensure safety.

1. Desirable genes from plants, animals, bacterial cells and transferred to plant cells. A piece of DNA containing the gene for a desired characteristic: a) The desired gene is identified. b) The gene is clipped out using DNA-cutting enzymes. c) Various techniques are used to transfer the gene into the plant cell. d) The gene migrates to the cell's nucleus is integrated into the plant's DNA. e) Modified plant cells are identified and placed into cell culture medium to multiply. f) Special culture medium allows the cells to differentiate into the various types of cells that make up a whole plant. g) Each mature plant carries the new gene and the trait for which it codes. 2. It can make food resistant to viruses. Contain enriched nutrients. By making plants resistant to herbicides, insects, and various plant disease, this technology has increased crop yields and reduced damage from insects and plant disease. By altering enzyme activity and other traits, biotechnology is being used to increase the shelf life of fresh fruits and vegetable and create product that greater consumer appeal. Also used in food processing. 3. Created health problems and environmental damage. Severe allergic reaction, obesity. Non-genetic species and varieties may eventually become extinct, and the genes for the traits they possess may be lost forever. An environmental concern about GM crops is that they will be used to the exclusion of other varieties, thereby reducing biodiversity. Another environmental issue is the possibility that GM crops will create "superweeds" producing a fast-growing weed that would compete with the domesticated species. There is also concern that crops that have been engineered to produce pesticide-resistant insects. 4. Premarket approval is required, and information about the safety of the new plants at a relatively early stage of development is asked to be provided to a FDA.

(2) LEARNING OBJECTIVES - Pathogens in Food: 1.Distinguish food-borne infection from food-borne intoxication. 2. Discuss three types of bacteria that commonly cause food-borne illness. 3. Explain how viruses, molds, and parasites can make us sick. 4. Describe how careful food handling can prevent food-borne illness.

1. Food-borne infection: any food-borne illness caused by pathogens hat multiply in the human body. bacteria itself infect the body or produce toxins with the body. Food-borne intoxication is caused by consuming a food that contains toxins produced by pathogens. 2. Salmonella - contaminated meat, dairy products, seafood, fresh produce, and cereal have caused outbreaks, bur poultry and eggs are foods most commonly contaminated with the bacterium. because it can be killed by heat, foods that are likely to be contaminated should be cooked thoroughly. Campylobacter jejuni - leading cause of acute bacterial diarrhea in developed countries. common sources are undercooked chicken, unpasteurized milk, and untreated water. it grows slowly in cold temperatures and is killed by heat, so careful storage and thorough cooking help prevent infection. Escherichia coli (E. coli) - is a bacterium that inhabits the gastrointestinal tracts of humans and other animals. It comes into contact with food through fecal contamination of water or unsanitary handling of food. There are different strains of E. coli that cause different symptoms. One strain of E. coli, found in water contaminated by human or animal feces, is the cause of "travelers' diarrhea." Another strain, E. coli O157:H7, produces a toxin in the body that causes abdominal pain, bloody diarrhea, and in severe cases a form of kidney failure called hemolytic-uremic syndrome. 3. Viruses make us sick by turning our cells into virus-producing factories. Mold produce toxins under certain conditions. When we consume it, we absorb toxins in our blood stream. Cooking and freezing stop mold growth but do not destroy toxins that have already been produced. Parasites can be transmitted through consumption of contaminated food and water with animal's feces or raw/undercooked meat. 4. Taking preventative measures such as a fight BAC method: clean - wash hand and surfaces often, separate - don't cross-contaminate, cook - cook to proper temperatures, and chill - refrigerate promptly.

(5) CONCEPT CHECK - Biotechnology: 1. Where does the DNA introduced into GM plants come from? 2. How does biotechnology increase crop yields? 3. Why might a GM food cause an allergic reaction when the unmodified food does not? 4. What types of GM foods carry special labels?

1. From plant, animal or bacterial cells. 2. By keeping them resistant to insects and plant disease. 3. Possibility that the nutrient content of a food may have been negatively affected or that an allergen or a toxin may have inadvertently been introduced into a food that was preciously safe. DNA from an allergen containing food. 4. Food manufacturers are not required to provide special labeling unless the food is known to pose a potential risk. The nutritional composition of the food has been altered; if it contains potentially harmful allergens, toxins, pesticides, or herbicides; if it contains ingredients that are new to the food supply; or if it has been changed significantly enough that its traditional name no longer applies.

(3) LEARNING OBJECTIVES - Agricultural and Industrial Chemicals in Food: 1. Illustrate how contaminants move through the food chain and into our foods. 2. Compare the risks and benefits of using pesticides with those of growing food organically. 3. Describe how to minimize the risks of exposure to chemical contaminants.

1. Some contaminants are eliminated from the environment quickly because they are broken down by microorganisms or chemical reactions. Others remain in the environment for very long periods, and when taken up by plants and small animals, they are not metabolized or excreted. When these plants or small animals are consumed by larger animals that are in turn eaten by still larger animals, the contaminants accumulate, reaching higher concentrations are each level of the food chain. This process called bioaccumulaion. 2. Risks of pesticides contaminating the environment and harmful to consumers. In organic food there are no pesticides which it eliminates the chance of contaminating with these chemicals. Benefits of pesticides it prevent plant diseases and insect infestations. And have higher crop yield food resulting to cheaper cost. However for food organic is produced using methods hat emphasize a reduction in the use of chemical pesticides and fertilizes, the recycling of resources, and the conservation of soil and water to protect the environment. Also it's healthier and is not chemically altered and has a lower impact on the environment. 3. Choosing a wide variety of foods, thus avoiding excessive consumption of contaminants that may be present in any one food. Washing and in some cases peeling fruits and vegetables. To minimize consumption of contaminants, remove the skin, fatty material, and dark meat from fish. Use cooking methods such as broiling, poaching, boiling, and baking, which allow contaminants from the fatty portions of fish to drain out.

(4) CONCEPT CHECK - Technology for Keeping Food Safe: 1. What is pasteurization? 2. How does irradiation help extend the shelf life of food? 3. How does modifies atmosphere packaging prevent food spoilage? 4. Why are food additives regulated?

1. The process of heating food products in order to kill disease-causing organisms. 2. Kills microbes and inactivate enzymes that cause germination and ripening of fruits and vegetables. 3. It uses plastics or other packaging materials that are impermeable to oxygen. The air inside the package is vacuumed out in order to remove the oxygen. The product can then remain packaged in a vacuum, or the package can be infused with another gas, such as carbon dioxide or nitrogen. The lack of oxygen prevents the growth of aerobic bacteria. 4. To prevent them from being harmful. Regulated to make food safer to eat with the additives in it. Also to make sure it doesn't cause cancer. Food additives improve food quality and help protect us from disease, but if the wrong additive is used or the wrong amount is added, it could do more harm than good.

Pathogen

A biological agent that causes disease.

Nitrosamine

A carcinogenic compound produced by reactions between nitrites and amino acids.

Acrylamide

A chemical formed in foods when starches and other carbohydrates are overheated (over 120*C or 250*F) during cooking; may be a carcinogen.

Polycyclic Aromatic Hydrocarbons (PAHs)

A class of mutagenic substances produced during cooking when there is incomplete combustion of organic materials -- for example, when fat drips on a grill.

Heterocyclic Amines (HCAs)

A class of mutagenic substances produced when there is incomplete combustion of amino acids during the cooking of meats -- for example, when meat is charred.

Delaney Clause

A clause added to the 1958 Food Additives Amendment of the Pure Food and Drug Act that prohibits the intentional addition to foods of any compound that has been shown to induce cancer in animals or humans at any dose.

Hemolytic-Uremic Syndrome

A disorder, usually in children, that occurs when an infection in the digestive system produces toxic substances that destroy red blood cells causing them to block capillaries, eventually resulting in kidney failure.

Bovine Spongifrom Encephalopathy (BSE)

A fatal neurological disease that affects cattle (mad cow disease) and may be transmitted to humans by consuming contaminated beef by-products.

Hazard Analysis Critical Control Point (HACCP)

A food safety system that focuses on identifying and preventing hazards that could cause food-borne illness.

Generally Recognized as Safe (GRAS)

A group of chemical additives that are considered safe, based on their long-standing presence in the food supply without harmful effects.

Bovine Somatotropin (bST)

A hormone naturally produced by cows that stimulates the production of milk. A synthetic version of this hormone is now being produced by genetic engineering.

Integrated Pest Management (IPM)

A method of agricultural pest control that integrates nonchemical and chemical techniques.

Prion

A pathogenic protein that is the cause of degenerative brain diseases called spongiform encephalopathies. Prion is short for proteinaceous infectious particle.

Critical Control Point

A possible point in food production, manufacturing, and transportation where contamination could occur or be prevented or eliminated.

Infant Bolulism

A potentially life-threatening disease in which the bacteria Clostridium botulinum grows within the baby's gastrointestinal tract.

Modified Atmosphere Packaging (MAP)

A preservation technique used to prolong the shelf life of processed or fresh food by changing the gases surrounding the food in the package.

Irradiation

A process that exposes foods to radiation in order to kill contaminating organisms and retard the ripening and spoilage of fruits and vegetables.

veriant Creutzfeldt-Jakob Disease (vCJD)

A rare, degenerative, fatal brain disorder in humans. It is believed that the persons who have developed vCJD became infected through their consumption of cattle products contaminated with BSE.

Genetic Engineering

A set techniques used to manipulate DNA for the purpose of changing the characteristics of an organism or creating a new product.

Botulism

A severe food-borne intoxication that results from consuming the toxin produced by Clostridium botulinum.

Accidental Contaminant

A substance not regulated by the FDA that unexpectedly enters the food supply.

Indirect Food Additive

A substance that is expected to unintentionally enter food during manufacturing or from packaging. Indirect food additives are regulated by the FDA.

Direct Food Additive

A substance that is intentionally added to food. Direct food additives are regulated by the FDA.

Food Additive

A substance that is intentionally added to or can reasonably be expected to become a component of a food during processing.

Prior-Sanctioned Substances

A substance that the FDA or the USDA had determined was safe for use in a specific food prior to the 1958 Food Additives Amendment.

Food-borne Illness

An illness caused by consumption of contaminated

Parasites

An organism that lives at the expense of another.

Genetically Modified (GM)

An organism whose genetic material has been altered using genetic engineering techniques; a product containing or produced by genetic modification.

Transgenic

An organism with a gene or group with a gene or group of genes intentionally transferred from another species or breed.

Polychlorinated Biphenyls (PCBs)

Carcinogenic industrial compounds that have found their way into the environment and, subsequently, the food supply. Repeated exposure causes them to accumulate in biological tissues over time.

Recombinant DNA

DNA that has been formed by joining DNA from different sources.

Organic Food

Food that is produced, processed, and handled in accordance with the standards of the USDA National Organic Program.

Food-Borne Intoxication

Illness caused by consuming a food containing a toxin.

Food-Borne Infection

Illness produced by the ingestion of food containing microorganisms that can multiply inside the body and produce effects that are injurious.

Microbes

Microscopic organisms, or microorganisms, including bacteria, viruses, and fungi.

Mold

Multicellular fungi that form filamentous branching growths.

Tolerances

The maximum amount of pesticide residues that may legally remain in food, set by the EPA.

Aseptic Processing

The placement of sterilized food in a sterilized package using a sterile process.

Bioaccumulaton

The process by which compounds accumulate or build up in an organism faster than they can be broken down or excreted.

Biotechnology

The process manipulating life forms via genetic engineering in order to provide desirable products for human use.

Pasteurzation

The process of heating food products in order to kill disease-causing organisms.

Cross-Contamination

The transfer of contaminants from one food or object to another.