Lecture
Outline
Chapter 12
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Food Safety Concerns
Chapter 12
Chapter Learning Outcomes
1. List some common types and sources of
microbes that can cause food-borne illness.
2. Identify the government’s role in protecting the
food supply.
3. Describe procedures that can reduce the risk of
food-borne illness.
4. Identify various food preservation methods.
5. List at least three functions of food additives.
6. Identify sources of contaminants in food.
7. Discuss the pros and cons of pesticide use.
Quiz Yourself
True or False

1.
Aflatoxins are the most common sources of food-borne
illness in the United States. T F
2.
In the United States, foods such as ready-to-eat cereals,
commercially canned vegetables, and orange juice are
common sources of food-borne illness. T F
3.
Certain fungi, such as button mushrooms, are safe to
eat. T F
4.
The Environmental Protection Agency (EPA) regulates
the proper use of pesticides in the United States. T F
5.
The best way to tell if a food is safe to eat is to smell it.
T F
Quiz Yourself
True or False

1. False Food-borne illness resulting from
aflatoxins rarely occurs in the United States.
2. False These foods are not common sources of
food-borne illness.
3. True Certain fungi, such as button mushrooms,
are safe to eat.
4. True The Environmental Protection Agency
(EPA) regulates the proper use of pesticides in
the United States.
5. False Smelling a food is not a reliable way to
test its safety.
Key Terms
• Bacteria
– Simple single-celled microorganisms
• Food-borne illness
– Illness caused by microscopic diseasecausing agents or their toxic by-products in
food
• Pathogens: Disease–causing microbes
• Food intoxication: Illness that results when
poisons produced by certain pathogens
contaminate food and irritate the intestinal tract
Protecting Our Food
• Food and Drug Administration (FDA)
– Regulates food sold in interstate trade
– Establishes standards for safe food manufacturing
• Department of Agriculture (USDA)
– Enforces food safety laws
• Environmental Protection Agency (EPA)
– Monitors quality of drinking water
– Regulates toxic substances and wastes
• Federal Trade Commission (FTC)
– Oversees consumer protection laws
Microbes in Food
• Certain food microbes are beneficial
– Alter the color, texture, taste, and other factors
in production
• hard cheese, raised bread, pickled foods, or alcohol.
• Other microbes contaminate food, making it unsafe
for humans.
– Contaminates include pathogens, insect parts,
pesticide residues, and metal fragments.
How Pathogens Enter Food
• Entrance can be from
air, water, soil,
sewage, or animals.
• To reduce risk of
illness, keep flies,
cockroaches, and
other vermin away
from food.
• Insert photo of fly on
meat from page 407
Common Routes for
Transmitting Pathogens
• Vermin
– Animals such as flies, cockroaches, mice, and rats that
live around sewage or garbage
• Poor personal hygiene
– Failure to wash hands after using the toilet or coming in
contact with sources of pathogens
• Improper food handling
– Cross-contamination or failing to keep foods at the
proper temperatures
Food-Borne Illness
• Illnesses generally involve the digestive tract
– Signs and symptoms include nausea, vomiting, diarrhea, and
intestinal cramps
– Incubation period can make identifying source of illness difficult
• The number of pathogenic microbes or amount of
toxin influences whether a person becomes ill.
• Populations at risk include:
•
•
•
•
Pregnant women
Very young children
Elderly persons
People who have serious chronic diseases or weakened
immune systems
Summary of Some High-Risk Foods and
Their Primary Pathogens
• Insert Table 12.1
Is It the Stomach Flu?
• Influenza (“the flu”)
– Viruses that infect
respiratory tract
• Characterized by coughing,
fever, weakness, and body
aches
• Food-borne illness
– Pathogens that infect
intestinal tract
• Characterized by intestinal
cramps, diarrhea, and
vomiting
Food-Borne Pathogens
• Bacteria — Single-celled microbes
– Certain bacteria require oxygen
– Common pathogenic bacteria: Campylobacter,
Clostridium, Escherichia, Listeria, Salmonella, and
Staphylococcus.
• Viruses — Genetic material coated with protein
• Parasites — Organism lives in/on other living
things
– Examples: Giardia, Cryptosporidium, Trichinella, and
Anisakis
• Fungi — Lives on dead/decaying organic matter
Common Sources of Food Borne Illness:
Bacteria
• Insert Table 12.2
Common Sources of Food Borne Illness: Viral
• Insert Table 12.3
Common Sources of Food Borne Illness:
Parasites
• Insert Table
12.3
Reducing Risk When Purchasing Food
• When shopping for groceries:
– Purchase frozen foods and highly perishable
foods, such as meat and fish, last.
– Avoid precut bagged produce or salads.
– Check “best by” dates on packages of
perishable foods. Choose products with the
latest dates.
– Don’t buy food in damaged containers.
– Don’t buy cartons with cracked eggs.
Reducing Risk When Purchasing
Food (continued)
• Purchase only pasteurized dairy foods and
juices.
• Purchase only the amount of produce for 1
week’s use.
• Pack meat, fish, and poultry in plastic bags to
avoid cross-contamination of other foods.
• After shopping, take groceries home
immediately.
• Refrigerate (or freeze) meat, fish, or poultry.
• Refrigerate eggs and milk products.
Reducing Risk: Food Preparation
• Use a fresh paper towel or clean hand towel
to dry hands.
• Before preparing foods, clean food
preparation surfaces with hot soapy water.
– A solution made by adding 1 tbsp bleach
to 1 gallon of water kills most pathogens.
• Use easy-to-clean, non-porous cutting
boards.
Reducing Risk: Food Preparation
(continued)
• Replace cutting boards when they
become streaked with cuts.
– Have 3 different cutting boards, one for
meats, the second for produce, and third
for breads.
• Sanitize food preparation surfaces and
equipment that came in contact with
meat, fish, or poultry.
Proper Hand Washing
• Wash hands thoroughly with hot, soapy water for
at least 20 seconds, before and after touching
food.
• Insert photo of hands and
sink from page 415.
Reducing Risk During Food Preparation
• Don’t use foods from containers that:
– leak, bulge, or are severely dented
– have damaged safety seals
– spurt liquid or have a bad odor
• Read product labels to determine proper
storage conditions.
• Wash fresh produce under running water to
remove surface dirt and bacteria.
Remember: When in doubt, throw it out.
Maintaining Proper Temperature
of Foods
• Most microbes grow well
when temperatures are
between 40o F to 140o F.
– Cooking food to the proper
temperature destroys foodborne pathogens.
• Microwave cooking can result
in uneven temperatures that
may not destroy all
pathogens.
• Insert figure
12.3
To Reduce Your Risk of
Food-Borne Illness
• Always thaw high-risk foods in the refrigerator,
under cold running water, or in the microwave.
• Cook foods immediately after thawing. Do not
refreeze.
• Marinate food in the refrigerator, and if
marinating meat, fish, or poultry, discard the
marinade.
• Don’t remove cold foods from the refrigerator or
hot foods from the stove until serving time.
Food Pathogens and Temperature
Raw Fish
•
Insert sushi photo from page 418.
• Eating raw fish is
safe for most
healthy people, if
the fish is very fresh
before being
commercially frozen
and then thawed
properly.
Ground Meats, Poultry, and Fish
• The interior portion of meat
contains no bacteria,
however, the surface may
contain bacteria.
• Grinding mixes pathogenic
bacteria throughout the meat.
• To avoid food-borne illness,
cook ground meats
thoroughly.
• Insert raw ground meat
photo from page 418.
To Reduce Your Risk of
Food-Borne Illness
• Cook beef, poultry, pork, thick pieces of
fish, and egg-containing dishes
thoroughly.
• Cook eggs until the yolk and white
solidify.
• Heat sprouts until they are steaming.
• Cooked seafood should lose its glossy
appearance and flake easily.
To Reduce Your Risk of
Food-Borne Illness (continued)
• Bake stuffing separately from
poultry.
• Serve meat, poultry, and fish on a
clean plate.
• During picnics, keep salads, desserts
and other perishable picnic foods on
ice.
Storing Food
• Refrigerate or freeze
left-over foods within 2
hours.
– If environmental
temperatures are >90o F,
refrigerate within 1 hr.
• Separate food into
shallow pans to ensure
faster cooling.
• Insert figure 12.7
Reducing Risk When Storing Foods
• Keep refrigerator temperature below 41°F.
• Cook or freeze ground meats and poultry soon after
purchasing.
• Cook raw fish, shellfish, and poultry the day they are
purchased.
• Use refrigerated ground meat within 1 to 2 days and
use frozen meat and patties within 3 to 4 months
after purchasing them.
• Use refrigerated leftovers within 4 days.
• Reheat leftovers to 165°F; reheat gravy to a rolling
boil.
Cold Storage Time Limits for Perishable Foods
• Insert Table 12.6
FIGHT BAC!
1. CLEAN
Wash hands and surfaces
often.
• Insert FIGHT BAC
from page 420.
2. SEPARATE
Don’t cross-contaminate.
3. COOK
Cook to proper temperature.
4. CHILL
Refrigerate promptly.
www.homefoodsafety.org
Food Spoilage
Summary of Food Preservation Methods
•
Insert Table 12.7
Home-Canned Foods
• Home-canned foods may
contain the deadly Clostridium
botulium and its toxin.
– Low acid foods, such as
corn and beans, are most
susceptible.
• Do not taste home-canned,
low-acid foods before they are
boiled for at least 10 min.
Irradiation
• Food irradiation preserves food
by using a high amount of
energy to kill pathogens.
– Process does not make foods
radioactive
• Used on spices, dry vegetable
seasonings, meats, seeds, shell
eggs, and fresh produce
• Irradiated foods (except dried
seasonings) must have the
Radura symbol on package.
• Insert figure
12.8
Preparing for Disasters
Water
• Store at least 1 gallon of water/person/day. Keep a 3
to 5 day supply.
• Keep water in a cool place and in sturdy plastic
containers.
• Store water away from toxic substances.
• Change stored water every 6 months.
• Drink only bottled, boiled, or treated water until public
water supply is safe.
• Fill a bathtub with water to use, if needed.
• Make sure the seal on bottled water has not been
broken.
Emergency Food Supply
• Store at least a 3-day supply of food for emergency use.
• Choose foods that have a long shelf life, require no
refrigeration, and can be eaten without cooking.
• Store a manual can opener, paper towels, and eating
utensils.
• Unopened canned and boxed foods should last 2 years.
• If there’s no electricity, eat foods in the refrigerator and
freezer before the emergency food supply.
• For more information, visit the CDC website:
www.bt.cdc.gov/disasters/
Food Additives
Food additive: any substance that
becomes incorporated in food during
production, packaging, transport, or
storage
– Direct or intentional additives are added to
foods to facilitate processing, increase
nutrient content, prolong freshness, enhance
taste, improve color, or make the food safe.
– Color additives include dyes, pigments, or
other coloring agents such as beta-carotene.
Common Types of Direct Food Additives
• Insert Table 12.9
Food Safety Legislation: Food
Additives
• Food Additives Amendment (1958)
– Required manufacturers to provide evidence that a
new additive is safe before use in products
• Generally Recognized a Safe (GRAS) — List of
ingredients used before 1958 that were thought
to be safe
– Exempt from safety testing
– GRAS list substances are not classified as additives
All new additives must undergo safety testing
before FDA grants approval.
Food Safety Legislation: Food
Additives
• Delaney Clause of the Food Additives
Amendment — prevents manufacturers from
adding a new compound to foods that causes
cancer at any level of intake
– Does not apply to pesticide residue
• The Food Quality Protection Act of 1996
established safety standards of “a reasonable
certainty of no harm” for pesticide residues.
Other Substances in Food
Unintentional food additives — substances
that are accidentally in foods
– FDA permits very small amounts of
unavoidable, naturally occurring substances
like dirt and insect parts in foods.
• Small amounts are not harmful when
consumed in minute amounts.
– Chemical contaminants like lead or mercury,
are naturally in our environment and may be in
foods.
Benzene
• Benzene is a cancer-causing agent in some
beverages and foods derived from natural or
from manufactured sources.
– In 2005, FDA received reports that low levels
of benzene were found in soft drinks that
contain ascorbic acid and benzoate salts.
• FDA’s Center for Food Safety and Applied
Nutrition sampled drinks and found either no
detectable amounts of benzene or amounts
within the allowable range.
What Are Pesticides?
• Pesticides: any substances used to control or kill
unwanted organisms
–
–
–
–
Insecticides — control or kill insects
Rodenticides — control or kill mice and rats
Herbicides — destroy weeds
Fungicides — limit spread of fungi
Pesticide Residue Tolerances — maximum amount
of pesticide residues allowed
Nonchemical Methods of Pest
Management
• Insert figure
12.10
• Integrated Pest Management
(IPM) involves methods that
control pests while limiting
damage to the environment.
– Examples: growing pest-resistant
crops, using predatory wasps, or
trapping adult insects
• Produce grown without pesticides
may be labeled as “organic.”
How Safe Are Pesticides?
• Pesticides have the potential to harm
humans, animals, and the environment.
– Once pesticides are applied to cropland,
they may remain in the soil, be taken up
by the plant root, enter groundwater and
other waterways, or be carried to other
locations by the wind.
• Each path can be a route to the human
food chain.
Pesticide Pathways
• Insert Figure 12.11
Chapter 12 Highlight
Avoiding “The Revenge”
Traveler’s Diarrhea (TD)
– Results from consuming food or water that has
been contaminated with pathogens
– Causes abrupt onset of abdominal cramps, loose
or watery bowel movements, nausea, vomiting,
bloating, and fever
– Generally lasts 3 to 4 days
Areas of Risk for Traveler’s Diarrhea
• Insert figure 12.A
Reducing Your Risk of TD
• Use caution when selecting foods and
beverages.
– Avoid food from street vendors,
undercooked meats, and raw foods
washed in water.
• Avoid contact with contaminated waterways.
• Sanitize drinking water and water for
brushing teeth or hand washing.
Sanitizing Water
• Boiling
• Using chemical disinfectants that
contain chlorine or iodine (These
products do not kill Crypto.)
• Filtering water
– Removes bacteria and protozoans but not
viruses
Preventive Medication
•• Before leaving the United States, consult a
physician.
• Bismuth subsalicylate (BSS) can reduce the
risk.
• Side effects of BSS can include nausea,
constipation, and blackening of the tongue
and bowel movements.