Judith E. Brown

Prof. Albia Dugger • Miami-Dade College

www.cengage.com/nutrition/brown

The Multiple Dimensions of Food Safety

Unit 32

Threats to Food Safety

• Each year, US foodborne illnesses cause:• Sickness in 76 million people• 325,000 hospitalizations•Over 5,000 deaths

Key Terms

• Foodborne illness• Illness related to consumption of foods or

beverages containing disease-causing bacteria, viruses, marine organisms, fungi, toxins, parasites, or other contaminants

How Good Foods Go Bad

• The most common contaminants (bacteria and viruses) enter the food supply during food processing, storage, or preparation

• Contamination through feces is common• From intestines in meat processing• From animal manure used on vegetable crops• From handling by people with dirty hands

Potential for Spreading Foodborne Illness

Contaminants In Foods

• Foods can be contaminated from the inside• Eggs of chickens infected with Salmonella• Shellfish that filter contaminants from water• Bacteria that enter fruits and vegetables with

broken skins

Cross-Contamination

• Cross-contamination occurs when food that is contaminated comes into contact with another food• At food processing plants•During preparation at home

Other Substances in Foods

• Foods can be contaminated with other substances that have been intentionally or unintentionally added• Antibiotics•Hormones• Pesticides and PCBs

Antibiotic Resistance

• Farm-raised animals are commonly given antibiotics in feed

• Microorganisms become resistant to the antibiotics and infect people – and infections caused by antibiotic-resistant organisms are difficult to treat

Hormones

• Farm-raised animals are commonly given hormones to promote growth or improve milk production

• The safety of consuming meat and milk products containing these hormones is under investigation

Pesticides and PCBs

• Pesticides containing organophosphates, mercury-containing fungicides, and DDT can cause foodborne illnesses

• PCBs from contaminated land and water have been linked to cancer

Pesticides and PCBs

• <1 in 10,000 foods contain excessive pesticide levels

• Farm workers are at greatest risk

Causes of Foodborne Illness

• Over 250 types of foodborne illnesses caused by infectious and noninfectious agents have been identified

• Effects range from nausea and diarrhea to death within minutes

High-Risk Groups

Top 4 Causes

Salmonella

• CDC estimates >1.4 million cases of Salmonella infection occur each year

• 5% of US population experience a Salmonella infection each year

Other Causes: Seafood

• Illnesses caused by seafood contaminated by water pollution• Mercury poisoning• Ciguatera poisoning• “Red tide” poisoning

Seafood

• Mercury contamination• In large fish from mercury-contaminated waters

• Ciguatera (neurotoxin)• In fish from reefs with toxic dinoflagellates

• “Red tide” (neurotoxin)• In shellfish that eat toxic microorganisms

Ciguatera Poisoning

• Tropical reef fish eat toxic dinoflagellates

• Poison cannot be destroyed, and there is no effective treatment

Other Causes: Botulism

• C. botulinum bacteria produce deadly toxin in airtight containers

• Foods in bulging containers should not be eaten

Other Causes: Parasites

• Parasitic tapeworms, flatworms, and roundworms enter food and water through fecal material and soil

• Most are killed by cooking or freezing

Other Causes: Mad Cow Disease

• Bovine spongiform encephalopathy (BSE)•Deadly disease caused by an infectious protein

(prion) – not destroyed by cooking• Started when cows were fed sheep body parts• Transmitted to humans who ate infected cows•Human disease may take 20 years to develop

Preventing Foodborne Illness

• There are two major approaches to prevention of foodborne illness: •Regulations that control food processing and

handling practices•Consumer behaviors that reduce risk of

consuming contaminated food

Food Safety Regulations

• The Federal Food, Drug, and Cosmetic Act regulates all substances added intentionally or accidentally to foods – except pesticides

• Pesticides with a “negligible risk” of health problem are permitted in foods

Irradiation of Foods

• Irradiation destroys bacteria, parasites, and viruses in foods

• Irradiation does not destroy prions, toxins, pesticides, mercury or PCBs – or prevent later contamination

The Consumer’s Role

• Food Safety Basics:• Scrub your hands thoroughly with soap and water

for at least 20 seconds•Cook foods thoroughly; keep hot foods above

140°F, and cold foods below 40°F•Don’t consume raw milk, meat, or eggs• Follow USDA safe handling instructions• Throw away canned foods that bulge out

Safe Cooking Temperatures

Safe Handling Temperatures

Safe Storage

USDA Safe Handling Instructions

Take Action:

• Until contamination of food is prevented, consumers must take responsibility for reducing risks of foodborne illnesses• Buy locally grown produce• Plant a vegetable garden• Buy irradiated raw meats• Buy only pasteurized dairy products