Transcript Food: It Shouldn`t Be a Mystery

Food: It Shouldn’t Be a
Mystery
Alan M. Tart
Regional Retail Food Specialist
U.S. Food and Drug Administration
Atlanta, GA
1
Objectives




Name several examples of chemical, physical,
and biological hazards found in food
Review principles of microbiological growth &
survival
Identify at least one nutritional risk in food
Discuss how to prevent, eliminate, or reduce
hazards/risks of concern
2
Foodborne Illness in the U.S.
3
The Problem – Foodborne Illness

Estimated 76 million illnesses

325,000 hospitalizations annually;
hospital stays estimated at more than
$3 billion

and 5,000 deaths!
Mead et al., Emerg. Infect. Dis. 5:607-625
4
Factors Affecting Foodborne
Illness in the U.S.






Globalization of the food
supply
Food consumption patterns
Methods/Surveillance/
Awareness
Changing production and
processing practices
Evolution of new strains
Increased longevity
5
Controlling Food Safety Hazards
6
Hazard
A physical, chemical, or biological
property that may cause an
unacceptable consumer health risk.
7
Physical Hazards

Poor handling
procedures in the
food flow

Examples: plastic,
bones, wood, glass,
metal fragments,
8
Naturally Occurring Chemical Hazards






Scombrotoxin
Ciguatera Toxin
Shellfish Toxins
Tetrodotoxin
Toxic Mushrooms
Allergens
9
Biological Hazards

Includes bacterial, viral, and parasitic
organisms
Dennis Kunkel
10
Percentage of Foodborne Illness
Attributable to Known Pathogens
Bacteria
30%
Protozoa
3%
Mead et al., 1999
Viruses
67%
11
Bacteria, Viruses, and Parasites –
What’s the Difference?

Bacteria grow in food and in the body


Bacterial Infection vs. Intoxication
Viruses and parasites cannot grow in food, only
in the body.
12
Factors Needed for Bacterial Growth






Food
Acidity
Time
Temperature
Oxygen
Moisture – Available Water
13
Oxygen Requirements of Bacteria
Aerobic
Oxygen Dependent
Facultative
Anaerobic
Oxygen Intolerant
14
Vegetative Bacteria

Found on many raw animal foods (meat, fish, eggs,
milk), as well as processed foods

Examples





Salmonella
E. coli O157:H7
Listeria monocytogenes
Vibrio spp.
Control Measures





Cooking
No bare hand contact with RTE food
Handwashing
Not working when ill
Temperature control
15
Staphylococcus aureus




High numbers of cells produce heat
stable toxin in ready-to-eat food
Caused by bare hand contact with
ready-to-eat food and temperature
abuse
Poor competitor on raw foods
Normal reheating will not destroy
toxin
16
Bacterial Spore Formation

Spore – survival mechanism for certain bacteria

Heat resistance exceeds normal cooking
temperatures

Spore-forming organisms




C. perfringens
C. botulinum
B. cereus
Control Measures


Proper cooling
Hot and cold holding
17
Clostridium botulinum



Proteolytic strains of Type A and B will
not grow below 10°C (50°F)
Non-proteolytic strains of type B and E
will not grow below 3.3°C (38°F)
C. botulinum will not grow at a water
activity of 0.94 or less
18
Recent Botulism Outbreaks



Most cases of botulism are due to homeprepared foods
Nearly all of the recent botulism outbreaks
due to commercial foods are the result of
extreme temperature abuse of refrigerated
foods (2 or more days at room temperature)
Outbreaks due to commercially processed low
acid canned foods are rare
19
Recent Botulism Outbreaks







Refrigerated pasta sauce in a plastic pouch
in a cardboard carton
Refrigerated bean dip in a 16 oz plastic tub
with a snap fit lid
Garlic in oil
Sautéed onions left in a warm skillet
overnight
Frozen shredded potato patty
Refrigerated carrot juice in a plastic bottle
Baked potato wrapped in foil
20
Foodborne Viruses

Hepatitis A


F.P. Williams, U.S. EPA
Noroviruses





83,000 cases (5% foodborne)
Formally known as Norwalk-like viruses
23M cases (40% foodborne)
Noroviruses are the #1 cause of foodborne
illness in the U.S. (67%)
Example outbreaks
Other viruses
Mead et al., 1999
21
Viruses and Cooking


Viruses display variable resistance to
heat
Important controls



No bare hand contact with ready-to-eat
food
Proper handwashing
Not preparing food when ill
22
Why Viruses are Such a Problem


10,000,000 - # of viral particles you start
with in 1 ml of feces
 1,000,000 - # of virus particles left after
properly washing your hands (2 log
reduction) (Ayliffe et al., 1978)
 100,000 - # of virus particles transferred
from an ungloved hand to food (10%)
(Montville, 2001)
In contrast, it takes ~10 virus particles to
make you sick
23
Behavioral Causes of Foodborne
Illness
24
Foodborne Illness Risk Factors

Food from Unsafe Sources

Inadequate Cooking

Improper Holding Temperatures


Contaminated Equipment/Cross
Contamination
Poor Personal Hygiene
25
Food from Unapproved Source
26
Food from Unapproved Source
27
Food from Unapproved Source
28
Unapproved Cheese Product
29
CDC’s EHS NET OUTBREAK/ NONOUTBREAK STUDY Contributing Factors Identified in Outbreaks,
EHS-NET, 2002-2003
Infected Person Handling
Food
C- Contamination Factors
P- Proliferation Factors
S- Survival Factors
Bare Hand Contact
Cross Contamination from
Raw Animal Food
Raw Food Contaminated at
Source
Holding Food at
Room
Temperature
Insufficient
Time/Temp. During
Initial Cooking
30
Nutritional Risks in Food
31
Nutritional Risk in Food


Obesity epidemic

Genetic causes

Environmental causes
Health risks associated with obesity
32
Questions?
Alan M. Tart
Regional Retail Food Specialist
U.S. Food and Drug Administration
60 8th Street, N.E.
Atlanta, GA 30309
[email protected]
(404) 253-1267
33