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Self-Check
The primary function of bile is toA. Digest lipidsB. Emulsify lipidsC. Digest proteinD. Emulsify proteinE. Protect the lining of the small intestine from HCl
http://www.youtube.com/watch?v=ZbH_mSk2dNk
Chapter 20:Food Safety and
Food Security
An overview of the players….
Microorganism (also known as pathogen, microbe):Microscopic living organism which multiplies under specific conditions and can cause illness in humans • Virus – Infectious agent containing genetic material + protein shell;
multiply in living cells of hosts, cannot multiply in foods• Parasite – Organism that lives on or in a host & obtain needed
nutrients from the host; cannot multiply in foods• Bacteria – Single celled microorganisms which increase in number by
doubling; multiply in foods when conditions are favorable for growth
• Under what conditions would “conditions be favorable” for bacterial growth?• Warm temperature (heat kills bacteria, while cold prevents bacteria from
multiplying)• Neutral pH (low acidic)• Low salt concentration • High moisture content • High oxygen levels
The take home message!
• If you are exposed to high levels of bacteria or toxins in food or beverages, you can get a…
• Foodborne Illness – a largely preventable disease or condition caused by consumption of a contaminated food or beverage• Mainly affects the GI tract• May also affect other systems in the body
Self-Check
What makes a nutrient essential?A. Your body does not produce itB. Your body produces some of it, but not enough for daily functionsC. You must get it in your diet to avoid deficienciesD. All of the above
Self-Check
RDAs and AIs are occasionally used on food labels.A. TrueB. False
Self-Check
The ____________ and ______________ make enzymes needed for digestion.A. Pancreas and liverB. Liver and kidneysC. Stomach cells and salivary glandsD. Pancreas and gallbladder
Self-Check
• Which type of microorganism can multiply in foods and cause illness if the food is consumed?
A. VirusB. ParasiteC. BacteriaD. Both B and CE. All other answers are correct
Types of Foodborne Illnesses• Foodborne Intoxication – an illness caused by ingesting foods that
contain a toxin• Naturally present• Produced by bacteria or fungi growing on foods• Contamination with chemicals
• Foodborne Infection – an infection that results in illness; caused by consuming foods contaminated with microorganisms that then multiply in the intestines.
Symptoms of Foodborne IllnessSymptoms commonly begin in the GI tract and may last hours or days. Common symptoms:• Nausea• Vomiting• Abdominal cramps• Diarrhea
Who is most at risk?• Those with decreased immune
function:• Infants• Children• Elderly• HIV/AIDS, Cancer, Diabetes• Pregnant women
Groups at Risk and Foods They Should Avoid
How Does Food Become Contaminated?
Microbes constantly surround us, and there are many
opportunities for food to become contaminated
Distribution of Foodborne Disease Outbreak-Associated Illnesses by the place where the food was prepared.
What is Food Safety?• Food Safety – the policies and
practices that apply to the production, handling, preparation, and storage of food in order to prevent contamination and foodborne illness
How is the food supply kept safe?
• HACCP – Hazard Analysis and Critical Control Points• Laws that require food manufacturers to follow safe processes• Inspectors in food processing plants• Locations on the food chain where foods are likely to be contaminated are
carefully self-monitored• Samples of meats and foods are tested for presence of harmful bacteria
Irradiation• Irradiation – Low
doses of radiation used to destroy insects and bacteria in foods • Not effective for ALL
foods• FDA has approved
irradiation of some meats, fruits, and vegetables, and spices
What can you do to keep your food safe?
Four Steps to Home Food Safety
CleanHands, surfaces, dishes, and fresh produce
Separate• Cross-Contamination – the
transfer of bacteria or pathogens from one source or surface to another• Separate ready-to-eat foods
and fresh produce from raw meat, seafood, poultry and eggs
Practically speaking, SEPARATE means….Preventing cross-contamination by….• Keeping meat and produce separate from each other everywhere• Place meat in plastic bags at the grocery store• Separate meat and produce in the grocery cart and shopping bags• Store meats beneath produce in the refrigerator
• During food preparation, clean cutting boards, knives, countertops and utensils with hot soapy water immediately after coming into contact with raw meat and eggs• Serving cooked foods on clean dishware (do not put grilled meats on
the same plate that contained raw meat juices)
Cook• Properly cooking meat helps to destroy pathogens•Meat must be cooked to a certain temperature in order to kill bacteria
Practically speaking, cooking means• Destroying bacteria with heat
• Keeping the holding temperature of cooked foods at 135 degrees Fahrenheit or higher to prevent bacterial growth after foods are cooked
• Microwaving leftovers to a temperature hot enough to kill bacteria
• NOTE: ground meats & casseroles are more susceptible to bacterial contamination and must be heated to a higher internal temperature
Chill• Promptly refrigerate perishable foods to a temperature of 41 degrees
Fahrenheit or less after purchase or preparation
• Refrigerate leftovers in shallow containers instead of deep containers
• Thaw foods in a way that minimizes bacterial growth
Temperature Danger Zone and Safe Thawing of Foods
The Danger Zone!
• Temperature in which bacterial grow quickly• 41 – 135 degrees
• The goal: Keep foods OUT of the danger zone!• Keep hot foods above 135• Keep cold foods below 41
Other rules for food safety
• Perishable foods left in the danger zone for two hours should be thrown out
• If in doubt, throw it out.
Organic Foods• Organic – grown and
processed using no synthetic fertilizers or pesticides• Many people believe organic
foods are healthier and safer• May help avoid chemicals,
but organic foods are just as susceptible to bacteria
USDA Organic Foods
Are organic foods more nutritious than conventionally grown foods?A. YesB. No
What does the research say about the benefits of organic foods?
2012 Review (240 studies)• No difference in nutrient content• No difference in E.coli contamination risk• No difference in allergy outcomes• Organic foods - less pesticide residue• Conventional foods – may have many different pesticide residues
http://annals.org/article.aspx?articleID=1355685
• Food Additives – any substance added to a food product• Maintain or improve
safety and freshness• Improve nutritional
value• To improve taste or
appearance
Food Additives
Genetically Modified Organisms (GMOs) • Genetically Modified Organism
(GMO) – living organisms whose genetic material has been altered through the use of genetic engineering• Increase yield• Improve resistance to pests
• Genetically Modified (GM) Foods – foods derived from GMOs
Pros and Cons of GMOs