NTRN 201 | Ch. 12 - Food and Water Safety, Food Technology

LO 12.1 Describe microbial foodborne illnesses and practices that can prevent them. • LO 12.2 Identify the categories of foods that most often cause foodborne illnesses. • LO 12.3 Compare potential advantages and drawbacks of organic and conventional foods. • LO 12.4 Compare the safety of drinking water from different sources. • LO 12.5 Describe the uses and safety characteristics of some common food additives. • LO 12.6 Summarize the advantages and disadvantages of producing foods through bioengineering

MICROBES + FOOD SAFETY

Who ensures our food supply is safe?

Health and safety agencies

• monitor and regulate food safety standards to protect the public

• conduct inspections and enforce regulations to prevent foodborne illnesses

Ex: Center for Disease Control and Prevention (CDC), Environmental Protection Agency (EPA), Food and Agriculture Organization (FAO), Food and Drug Administration (FDA), US Department of Agriculture (USDA), World Health Organization (WHO)

FDA areas of concern

• microbial foodborne illness

• natural toxins in foods

• residues in food (environmental contaminants, pesticide residues, + animal drugs)

• nutrients in food

• intentional approved food additives

• genetically engineered foods

foodborne illness

• caused by microorganisms (microbes + pathogens)

• caused by infection (Salmonella bacteria or hepatitis virus)

• caused by enterotoxins or neurotoxins

• life-threatening for certain people

organisms responsible for foodborne infections

Campylobacter, Clostridium perfringens, Escherichia coli (E. coli), Listeria, Norovirus, Salmonella, Toxoplasma

organisms responsible for food borne intoxications

Clostridium botulinum, Staphyloccus aureus

most frequent food sources of foodborne illnesses

raw/undercooked meat/poultry, unpasteurized milk, contaminated water, raw fruits and vegetables, person-to-person contact, raw foods in general, improperly refrigerated stuff

main categories

protein foods (ground meat, stuffed poultry, raw + undercooked eggs, seafood, raw milk products)

most common onset/general symptoms

diarrhea, vomiting/nausea, abdominal pain, fever, headache, muscle pain

prevention methods

cooking foods thoroughly, using sanitary food-handling methods, using pasteurized milk, use treated/boiled/bottled water, use proper canning methods

table

table

food safety from farm to plate (process)

• farm

  • (workers must use safe methods of growing/harvesting'/sorting etc. food to minimize contamination hazards)

• processing

  • (follow FDA guides for contamination, cleanliness, + education/training of works; must monitor for safety at critical control pts)

• transportation

  • (containers + vehicles transportating food must be clean; cold food must be kept cold at all times)

• retail

  • grocery store + restaurant employees must follow FDA food code on preventing foodborne illnesses, establishments must pass local health inspections + train staff in sanitation

• plate

  • consumers learn + use sound food safety principles + be mindful of foodborne illness

food safety from farm to plate (notes)

• how outbreaks occur (contamination in farm to plate chain)

• food safety modernization act (food safety system shifted from responding to preventing outbreaks)

• food industry controls (inspections + Hazard Analysis of Critical Control Point (HACCP))

• consumer safety at the grocery store (know what packaging dates mean)

sell by

AKA pull date, specifies food shelf life, food after this date may still be safe for consumption if it has been handled + stored properly

best if used by

AKA freshness date or quality assurance date, specifies the last date the food will be of the highest quality, food after this date will hv diminishing quality

expiration date

the last day the food should be consumed (except eggs —> last day eggs may be sold as “fresh eggs”)

pack date

the day the food was packaged or processed

safe food practices for individuals

• food provides ideal conditions (nutrients, moisture, warmth 40°F to 140°F)

• 4 core practices to defeat bacteria (clean, separate, chill, cook)

clean

keep hands, utensils, + surfaces clean w/ soap + warm water

separate

keep raw foods separated from ready-to-eat foods, avoid cross-contamination

ex: raw eggs, meat, poultry from other food

cook

use proper temps to kill microbes + keep hot foods hot (hold at 140°F or higher)

chill

refrigerate/freeze food promptly + keep cold foods cold (40°F or below)

protein foods

• likely to cause foodborne illness

ground meats - more processing, more opportunities to be contaminated

stuffed poultry - stuffed turkey (making it even bigger)

raw/undercooked eggs

seafood - official advice is to not eat raw seafood

raw milk products

raw seafood myths

if raw seafood was eaten in the past without problems, it is safe to do today

drinking alcohol with raw seafood will kill the germs

putting hot sauce on raw seafood will kill the germs

raw seafood truths

each harvest has separate risks, seafood is increasingly contaminated

alcohol cannot make contaminated raw seafood safe

hot sauce has no effect on microbes in seafood

raw produce and other foods

• likely to cause foodborne illness

raw produce - due to contamination at the farm level (wash to prevent, even if dont eat skin/peel)

unpasteurized juices - fresh juices

sprouts - wash them, careful about pack date

imported foods - different countries have different safety regulations

honey - botulism (dont give to anyone under 1)

picnics and lunch bags - likely to land in temperature danger zone

take-out foods and leftovers - likely to land in temperature danger zone

advances in microbial food safety

irradiation and modified atmosphere packaging

irradiation benefits

control of foodborne illnesses

preservation

control of insects

delay of sprouting and ripening

sterilization

irradiation concerns

nutritional loss

the formation of new chemical compounds

environmental risks

modified atmosphere packaging benefits

inhibits growth of aerobic microbes

prevents discoloration

prevents spoilage of fats

slows ripening of produce

natural toxins

herbs

cabbage family

foods with cyanogens

seafood red tide toxin

herbs

Belladonna and hemlock are infamous poisonous herbs, but sassafras is also toxic; it contains the carcinogen and liver toxin safrole, which is so potent that it is banned from use in foods and beverages

cabbage family

Raw cabbage, turnips, mustard greens, and radishes all contain small quantities of harmful goitrogens, compounds that can interfere with thyroid hormone production and when eaten in excess, enlarge the thyroid gland

foods with cyanogens

Cyanogens, precursors to the deadly poison cyanide, are found in bitter varieties of cassava, a root vegetable staple for many people. Most cassava is low in cyanogens. Apricot and cherry pits present the cyanogen amygdalin, a fake cancer cure often passed off as a vitamin. a This poison kills cancer cells but only at doses that can kill the person, too. Other fruit pits contain lower concentrations

seafood red tide toxin

Seafood may occasionally become contaminated with the so-called red tide toxin from algae blooms. Eating the contaminated seafood can cause paralysis.

pesticides benefits

protecting crops and controlling disease vectors

pesticides risks

residues left on produce, can negatively impact the health of vulnerable individuals

pesticides regulation

reference dose

natural pesticides

often made from household items

ways to reduce pesticide residue exposure

• Trim the fat from meat and remove the skin from poultry and fish; discard fats and oils in broths and pan drippings.

• Select fruit and vegetables with intact skins.

• Wash fresh produce in running water. a Use a soft brush, and rinse thoroughly.

• Use a knife to peel an orange or grapefruit; do not bite into the peel.

• Discard the outer leaves of leafy vegetables such as cabbage and lettuce.

• Peel waxed fruit and vegetables; waxes don’t wash off and can seal in pesticide residues.

• Peel vegetables such as carrots and fruit such as apples when it seems necessary.

• Choose organically grown foods, which generally contain fewer pesticides.

animal drugs

antibiotics, bovine growth hormone (BGH), arsenic

environmental contaminants

bioaccumulation and toxicity

heavy metals (mercury, PCBs and other chemicals)

Discuss mercury levels in seafood and why it is important to minimize your consumption of mercury.

Mercury escapes from many industries, power plants, and natural

sources into the Earth’s waterways, where bacteria in the water convert

it into a highly toxic form, methylmercury. Methylmercury then

concentrates in the flesh of large predatory species of fish. Cooking

and processing do not diminish mercury in seafood. Mercury damages

living tissues and the developing brain, and pregnant women, lactating

women, and children are the most vulnerable to mercury toxicity.

Currently, for most people, the benefits of eating safer varieties of

seafood far outweigh the risks. Small, younger fish tend to have lower

mercury levels. Large fish have the highest concentrations of mercury

due to bioaccumulation. Tilefish, swordfish, king mackerel, and shark

tend to have the highest mercury levels

water safety and sources

only 1% drinking water is potable (fit for human consumption), comes from surface or groundwater

tap water safety: chlorination

bottled water: not safer/healthier, microplastics

food-safety myths

five-second rule

if it tastes and smells ok, safe to eat

we have always handled our food this way so it must be safe

i sampled it a couple hours ago and didnt get sick, so its safe to eat

food-safety truth

food dropped is contaminated the moment it lands (on microbe-laden hard surface)

most microbial contamination is undetectable by human senses

past generations did not recognize causes of illness

illnesses often take half a day or longer to develop

regulation and usage of food additives

FDA requirements – manufacturer must prove additive is effective, additive measured in final product

Generally Recognized as Safe (GRAS) List

Margin of safety

risks and benefits

food additives

antimicrobial agents (preservatives)

antioxidants (preservatives)

artificial colors

artificial flavors, flavor enhancers

bleaching agents

chelating agents (preservatives)

nutrient additives

stabilizing and thickening agents

antimicrobial agents

Prevent food spoilage by mold or bacterial growth

Ex: Acetic acid (vinegar), benzoic acid, nitrates and nitrites, propionic acid, salt, sugar, sorbic acid

antioxidants

prevent oxidative changes and delay rancidity of fats; prevent browning of fruit and vegetable products

Ex: BHA, BHT, propyl gallate, sulfites, vitamin C, vitamin E

artificial colors

Add color to foods.

Ex: Certified food colors such as dyes from vegetables (beet juice or beta-carotene) or synthetic dyes (tartrazine and others)

artificial flavors, flavor enhancers

Add flavors; boost natural flavors of foods

Ex: Amyl acetate (artificial banana flavor), non- nutritive sweeteners, MSG (monosodium glutamate), salt, spices, sugars

bleaching agents

Whiten foods such as flour or cheese.

Ex: peroxides

chelating agents

Prevent discoloration, off flavors, and rancidity

Ex: Citric acid, malic acid, tartaric acid (cream of tartar)

nutrient additives

Improve nutritional value.

Ex: Vitamins and minerals.

stabilizing and thickening illnesses

Maintain emulsions, foams, or suspensions or lend the desired thick consistency to foods

Ex: Dextrins (short glucose chains), pectin, starch, or gums such as agar, carrageenan, guar, and locust bean.

bioengineered foods

most people consume foods that are products of bioenginnering

• recombinant DNA technology

• selective breeding

positives for GMOs

golden rice

mass production of insulin and rennin

greater crop yields

faster growing fish

GMO concerns

overdoses of nutrients or phytochemicals

accidental ingestion of drugs

pesticide residues

environmental effects (outcrossing, wildlife)

ethical arguments