Food Safety & Toxicology

What is Food Safety? Food Safety is making a food safe to eat and free of disease causing agents such as: Too many infectious agents Toxic chemicals Foreign objects

What is Food Quality? Food Quality is making a food desirable to eat with regards to good taste, color, and texture; bad food quality can be judged by: Bad color Wrong texture Smells bad

Unacceptable Foods Poor QualityUnsafe bad colortoo many bacteria wrong texturetoxic chemicals smells badforeign objects

Hazard A biological, chemical or physical agent that is reasonably likely to cause illness or injury in the absence of its control

What are the Type of Food Hazards? Biological: bacteria, viruses, parasites Chemical: heavy metals, natural toxins, sanitizers, pesticides, antibiotics Physical: bone, rocks, metal

A. Biological Hazards Microorganisms Yeast Mold Bacteria Viruses Protozoa Parasitic worms

How Do Foods Become Contaminated?

What do microorganisms need? Food Water Proper temperature Air, no air, minimal air

Bacterial Hazards Food infection and food intoxication Sporeforming and nonsporeforming bacteria

Sporeforming Bacteria (Pathogens) Clostridium botulinum Proteolytic Nonproteolytic Clostridium perfringens Bacillus cereus

Nonsporeforming Bacteria Brucella abortis, B. suis Campylobacter spp. Pathogenic Escherichia coli (e.g., E. coli O157:H7) Listeria monocytogenes Salmonella spp. (e.g., S. typhimurium, S. enteriditis) Shigella spp. (e.g., S. dysinteriae) Pathogenic Staphylococcus aureus (e.g., coagulase positive S. aureus) Streptococcus pyogenes Vibrio spp. (e.g., V. cholerae, V. parahaemolyticus, V. vulnificus,) Yersinia enterocolitica

In meat and poultry: Salmonella bacteria (poultry and eggs) Trichinella spiralis parasite (pork) On fruits and vegetables: E. coli bacteria (apple juice) Cyclospora parasite (raspberries) Hepatitis A virus (strawberries)

Viral Hazards Very small particles that cannot be seen with a light microscope Do not need food, water or air to survive Do not cause spoilage Infect living cells and are species specific Reproduce inside the host cell Survive in human intestines, water or food for months Transmission usually by fecal-oral route and related to poor personnel hygiene

Control of Viruses No Virus survives heating at 140 ° F (60 o C) for 30 minutes Inactivated by boiling at 212 ° F Hand sanitizers/antiseptics ineffective Important controls No bare hand contact with ready-to-eat food Proper handwashing Not preparing food when ill

Parasites in Foods Parasites are organisms that need a host to survive Thousands of kinds exist worldwide, but only about 100 types are known to infect people through food contamination Two types of concern from food or water: Parasitic worms [e.g., roundworms (nematodes), tapeworms (cestodes), flukes (trematodes)] Protozoa Role of fecal material in transmission of parasites

Parasitic Protozoa and Worms Roundworms (nematodes) Anisakis simplex Ascaris lumbricoides Pseudoterranova dicepiens Trichinella spiralis Tapeworms (cestodes) Diphyllobothrium latum Taenia solium, T. saginata Flukes (trematodes) Protozoa Cryptosporidium parvum Entamoeba histolytica Giardia lamblia

Foodborne Illness

Percentage of Foodborne Illness Attributable to Known Pathogens Mead et al., 1999

What is a Foodborne Illness? Foodborne illnesses are caused by agents that enter the body through the ingestion of food. Every person is at risk of foodborne illness. May be serious for very young, very old, people with long term illness Reaction may occur in a few hours or up to several days after exposure Symptoms Abdominal cramps, headache, vomiting, diarrhea (may be bloody), fever, death

What is the Impact of Foodborne Illness? In the US (Centres for Disease Control and Prevention) annually: 76 million cases of foodborne diseases 325,000 hospitalization 5,000 deaths In China (1994) Salmonella Outbreak : estimated 224,000 persons

Why is Foodborne Illness increasing in the US? Food: Preference for “ rare ” meats Increase shelf life of products which allow for bacterial growth Increase consumption of imported ready-to-eat foods

How can you prevent Biological Hazard to Foods? Prevention of microbes growing Holding at low temperatures (<40 o F) Cooling from 140 o -40 o F quickly Cooking helps to kill microbes >165 o F(73 o C) for poultry and eggs >155 o F (68 o C) for ground beef >160 o F (71 o C) for pork

Food from Unapproved Source

Unapproved Cheese Product

B. Chemical Hazards in Food Chemical hazard: a toxic substance that is produced naturally added intentionally or un- intentionally Naturally-occurring: Natural toxins (aflatoxins) Added intentionally: Antibiotics, preservatives Added non-intentionally: Cleaning agents, Pesticide residues

Intentionally Added Chemicals - Food Additives Preservatives (e.g., nitrite and sulfiting agents) Nutritional additives (e.g., niacin, vitamin A) Color additives (e.g., FD&C Yellow No. 5)

Unintentionally or Incidentally Added Chemicals Agricultural chemicals e.g., pesticides, fungicides, herbicides, fertilizers, antibiotics and growth hormones Toxic elements and compounds e.g., lead, zinc, arsenic, mercury, cyanide Secondary direct and indirect e.g., lubricants, cleaning compounds, sanitizers, paint

Mercury

Polluting with HG

MeHg kid

C. Physical Hazards In Food Physical hazard: a hard foreign object that can cause illness or injury Examples: plastic, bones, wood, glass, metal fragments Poor handling procedures in the food flow

Hazard Analysis Critical Control Point (HACCP)

What is Hazard Analysis Critical Control Point (HACCP)? The purpose of HACCP is to help ensure the production of safe food The goal of HACCP is to prevent and/or minimize risks associated with biological, chemical, and physical hazards to acceptable levels It is based on PREVENTION rather than detection of hazards Pioneered in the 1960 ’ s: first used for the space program (Pillsbury & NASA)

What are the Steps involved in HACCP? 1. Identify hazards 2. Determine Critical Control Points (CCPs) 3. Determine safety limits for CCPs 4. Monitor CCPs 5. Corrective action 6. Record data 7. Verify that the system is working

Good Practices in Food Chain  Good Agricultural Practices (pesticide use)  Good Catering Practices (ensure food served is safe)  Good Hygiene Practices  Good Manufacturing Practices  Good Storage Practices  Good Transport Practices

Shared responsibility GovernmentConsumerIndustry Food legislation/ enforcement Educated publicGood practices by producers & distributors Consumer educationSafe food practice in home Appropriate process & technology

Safe Eating …….