Module 1: Understanding Hazards Associated with Foods

Cooperative Extension Services

of Purdue University and Virginia Tech

Food Safety and Food Quality

• Food Safety: making a food safe to eat; free of disease causing agents

• Food Quality: making a food desirable to eat; good taste, color, and texture

Unacceptable Foods

Poor Quality Unsafe

bad color too many bacteria

wrong texture toxic chemicals

smells bad foreign objects

What are the Hazards in our Food?

• Biological: bacteria, viruses, parasites

• Chemical: sanitizers, pesticides, antibiotics

• Physical: bone, rocks, metal

How Do Foods Become Contaminated?

Controlling the Hazards

• Time and Temperature

• Separation

Biological Hazards

“Biological” means “living”

Biological hazards in foods include:

• Bacteria: Salmonella in chicken and eggs, E. coli in beef, Shigella in water

• Viruses: Hepatitis in water

• Parasites: Cryptosporidium and Cyclospora in water and produce

Examples ofBiological Hazards

In Meat and Poultry:

• Salmonella bacteria (poultry and eggs)

• E. coli bacteria (beef and ground beef)

• Trichinella spiralis parasite (pork)

Examples of Biological Hazards

On Fruits and Vegetables:

• Salmonella bacteria (bean sprouts)

• E. coli bacteria (apple juice)

• Cyclospora parasite (raspberries)

• Hepatitis A virus (strawberries)

Examples of Biological Hazards

$5,000 Cash or ... $1 doubled every 15 minutes for 4 hours

Time $5,000 $1.00

Beginning $5,000 $1

After 15 minutes $5,000 $2

After 30 minutes $5,000 $4

After 1 hours $5,000 $16

After 2 hours $5,000 $256

After 3 hours $5,000 $4096

After 4 hours $5,000 $65536

Control of Biological Hazards

Hazards are controlled by:• Controlling and monitoring storage and

processing temperature

• Preventing cross-contamination

• Following the cleaning and sanitation program

Control Using Temperature

Cooking helps to kill microbes

• >165oF for poultry and eggs• >155oF for ground beef• >160oF for pork

Holding at low temperatures (<40oF) prevents microbes from growing

Cooling from 140o-40oF quickly helps prevent microbes from growing

Chemical Hazards

• Chemical hazard: a toxic substance that is produced naturally, is added intentionally or non-intentionally

• Naturally-occurring: toxic substances produced by other living organisms

• Added intentionally: nitrates in meat, pesticide residues in feed

• Added non-intentionally: any unwanted substance (cleaning agents)

• Unidentified / wrong ingredient (colors)

Examples of Chemical Hazards

In Meat and Poultry

• Nitrate agents (red meat)

• Aflatoxins, pesticides (feed)

• Growth hormones (livestock)

• Growth promoting drugs (poultry)

• Cleaners, sanitizing agents (meat and poultry)

Examples ofChemical Hazards

Control of Chemical Hazards

• Approved and legal chemicals (cleaners, sanitizers, hormones, pesticides)

• Use a safe level• Letters of guarantee and vendor certification• Proper procedures and rinsing (cleaners

and sanitizers)• Storage of feed (aflatoxin)• Storage and labeling for ingredients and

raw materials

Physical Hazards

Physical hazard: a hard foreign object that can cause illness or injury

• Inherent to the food or ingredient

• Contaminant during processing

Examples of Physical Hazards

In the food or ingredients• Bone fragments (ground beef)• Feathers from animal carcass (turkey)

Contamination during processing• Stones, rocks, dirt in vegetables• Metal from processing equipment (ground

beef)• Jewelry, fingernails (food handler)

Control of Physical Hazards

Separate and remove physical objects

• Filter or sieve (meat grinder)

• Water bath (vegetables)

• Metal detector (all foods)

• Good employee practices (jewelry)

• Good sanitation and quality control programs