Ch. 12 Protecting our Food Supply

What practices are prohibited in organic farming

• Synthetic pesticides

• fertilizers

• hormones

• antibiotics

• sewage sludge

• genetic engineering

• irradiation.

What practices are used in organic farming

• Biological pest management

• composting

• manure use

• crop rotation

What does the USDA organic seal indicate

Food grown on farms certified under the Organic Foods Production Act of 1990.

Why do people choose organic foods

To reduce pesticide exposure, protect the environment, and improve perceived diet quality.

Are organic foods more nutritious than conventional

No significant nutrient differences

• organic label isn’t a guarantee of better health

What is food biotechnology

Genetic engineering using recombinant DNA to alter an organism for improved yield or quality.

What crops make up most U.S. GMO production

Corn and soybeans

Are FDA-approved GMOs considered safe

Yes, FDA states approved GMOs are safe to consume.

Benefits of GMO crops

35 % less pesticide use, >20 % higher yield, ≈70 % higher farmer profit

Goals of sustainable agriculture

Meet food needs, protect environment, use resources efficiently, maintain farm economy, and improve community life.

Why is locally grown food popular

Transparency, freshness, lower transport cost, supports local economy

• not proven safer.

True or False: a localvore eats local grown food when possible

true

Definition of a pesticide

Substance that prevents, destroys, repels, or mitigates pests including insects, weeds, fungi, and rodents.

Why use pesticides

Increase yield, lower food cost, improve appearance, and prevent natural carcinogen formation.

How does pesticide safety depend on exposure

Depends on toxicity, concentration, intake frequency, and individual susceptibility.

What did the USDA Pesticide Data Program find

99 % of foods below EPA limits; ≈40 % with no detectable residue.

What do the EWG “Dirty Dozen” and “Clean 15” lists caution

Even high-residue produce is typically far below EPA safety thresholds.

How to reduce pesticide exposure

Wash produce, peel and trim, discard outer leaves, vary food sources, and choose organic when desired.

What fish contaminants cause concern

Mercury and polychlorinated biphenyls (PCBs).

Who should avoid high-mercury fish

Pregnant women; avoid swordfish, shark, tilefish, king mackerel.

Safe fish consumption guideline

Up to 12 oz of low-mercury fish 2x weekly.

How does the FDA evaluate food additives

Reviews composition, amount consumed, health effects, and safety factors.

Why are food additives used

Prevent spoilage, preserve color/flavor, inhibit microbes, and ensure safe distribution

What is the GRAS list

“Generally Recognized As Safe” substances exempt from pre-market review, established 1958.

Who ensures substances don’t belong on the GRAS list

The FDA.

Information required for new additive approval

Identity, composition, manufacture, measurement in foods, purpose, and proof of safety.

When can additives not be approved

If used to hide defects, deceive consumers, or are unnecessary.

U.S. vs E.U. additive regulation difference

EU uses precautionary principle

U.S. requires proof of harm

How many Americans get foodborne illness yearly

≈48 million cases, 128 000 hospitalizations, 3 000 deaths.

Groups most at risk for foodborne illness

Infants, children, elderly, pregnant women, immunocompromised, and chronically ill.

Modern trends increasing foodborne risk

More raw foods, dining out, long supply chains, and global trade.

Foods where microbes grow best

Moist, protein-rich foods with neutral or slightly acidic pH.

Traditional food preservation methods

Salting, sugaring, smoking, fermenting, and drying to limit microbial water use.

Modern preservation methods

Pasteurization, refrigeration, freezing, and canning.

Danger-zone temperature range for bacteria

40 °F–140 °F (4–60 °C).

Can bacteria grow in the refrigerator

Most cannot, but Listeria can.

Do high temperatures destroy bacterial toxins

No, they kill bacteria but not toxins.

Three ways bacteria cause illness

Infection (invade intestinal wall)

toxin-mediated infection (colonize GI)

intoxication (secrete toxin into food)

Leading viral cause of foodborne illness

Norovirus.

How does Norovirus spread

Through contaminated food, water, and surfaces

• survives freezing and chlorination.

What are parasites? How are they transferred?

live in or on another organism (host)

• person-to-person in contaminated food/water/soil

93+ known parasites

Where are parasitic infections most common

Tropical regions with poor sanitation.

Main U.S. food safety steps

Clean, Separate, Cook, Chill.

Proper hand-washing?

20–30 seconds with warm soapy water before and after handling food.

Cutting-board safety

Use separate, nonporous boards

• avoid wood with cracks

***MINIMIZE cross-contamination*

How to wash produce

Under running water

• remove moldy or damaged areas

Should you follow the 5-second rule

No, dropped food picks up bacteria instantly.

Safe shopping tips

Select perishables last, avoid damaged packages, buy pasteurized dairy, and check expiration dates.

How to thaw food safely

In refrigerator, under cold running water, or microwave on defrost.

General rule for raw animal foods

Do not eat raw

• cook stuffing separately.

Safe outdoor cooking practice

Cook fully on-site

• never reuse plates from raw meat.

How to cool leftovers safely

Cool to 70 °F within 2 h and to 40 °F within 4 h.

Safe refrigerator temperature

Below 40 °F (4.4 °C)

How long to keep leftovers refrigerated

Only recommended times per foodsafety.gov.

Safe reheating temperature

165 °F (74 °C).

Where to store high-risk foods in fridge

On lower shelves to avoid drips.

How to maintain fridge safety during power outage

Keep doors closed as much as possible.

Best way to prevent cross-contamination

Keep raw meat separate from ready-to-eat foods.