Transcript The Microworld

Microorganism
Small, living organism
Pathogen
Disease-causing
microorganism
Toxin
Poison
Spoilage Microorganism
Microorganism that causes spoilage,
but not illness
2-2
Microorganisms That Can Contaminate
Food And Cause Foodborne Illness
Bacteria
Viruses
Parasites
Fungi
2-3
Basic Characteristics
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Living, single-celled
Can be carried by food, water,
humans, and insects
Can reproduce rapidly
under favorable conditions
2-4
Basic Characteristics (continued)
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Some survive freezing
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Some form spores
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Some spoil food; others cause illness
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Some produce toxins that cause illness
2-5
Growth Stages Of Bacteria
2-6
Bacterial Growth
2-7
What Microorganisms Need To Grow
2-8
Food
Microorganisms require
nutrients found in potentially
hazardous food to grow
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Proteins
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Carbohydrates
2-9
Acidity
Microorganisms grow well
in food with a slightly acidic
to neutral pH (4.6 to 7.5)
Raw Chicken
pH = 5.5 - 6.4
Egg Yolks
pH = 6.0 - 6.3
2 -10
Temperature
TDZ = 41˚F to 140˚F (5˚C to 60˚C)
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Most microorganisms
grow well in the TDZ
Some survive and grow
outside the TDZ
2 - 11
Time
Foodborne microorganisms
can grow to harmful levels if
they remain in the TDZ for
more than four hours
2 - 12
Oxygen
Different foodborne
microorganisms have different
oxygen requirements
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Some need oxygen to grow
(aerobic)
Some grow only when oxygen
is absent (anaerobic)
Most grow with or without
oxygen (facultative)
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Moisture
Most potentially hazardous
food has a water activity (aw)
of .85 or higher
Raw chicken
aw = .95 - 1.0
2 - 14
Barriers For Controlling The Growth
Of Microorganisms
Make food
more acidic
Raise or lower
the temperature
of food
Lower the
food’s
water activity
Minimize time
food spends in
the TDZ
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Caused By Bacteria
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Bacillus cereus
Listeriosis
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Botulism
Staphylococcal
Gastroenteritis
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Campylobacteriosis
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Hemorrhagic colitis
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Vibrio spp.
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Yersiniosis
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Salmonellosis
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Shigellosis
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Clostridium
perfringens
Gastroenteritis
Gastroenteritis
Gastroenteritis
2 - 16
Illness: Salmonellosis
Bacteria: Salmonella spp.
Type of Illness: Infection, possibly toxin-mediated
2 - 17
Illness: Salmonellosis
(continued)
Bacteria: Salmonella spp.
Type of Illness: Infection, possibly toxin-mediated
2 - 18
Illness: Listeriosis
Bacteria: Listeria monocytogenes
Type of Illness: Infection
2 - 19
Illness: Listeriosis
(continued)
Bacteria: Listeria monocytogenes
Type of Illness: Infection
2 - 20
Illness: Staphylococcal
Gastroenteritis
Bacteria: Staphylococcus aureus
Type of Illness: Intoxication
2 - 21
Illness: Staphylococcal
Gastroenteritis (continued)
Bacteria: Staphylococcus aureus
Type of Illness: Intoxication
2 - 22
Illness: Clostridium perfringens
Gastroenteritis
Bacteria: Clostridium perfringens
Type of Illness: Toxin-mediated infection
2 - 23
Illness: Clostridium perfringens
Gastroenteritis (continued)
Bacteria: Clostridium perfringens
Type of Illness: Toxin-mediated infection
2 - 24
Illness: Botulism
Bacteria: Clostridium botulinum
Type of Illness: Intoxication
2 - 25
Illness: Botulism
(continued)
Bacteria: Clostridium botulinum
Type of Illness: Intoxication
2 - 26
Illness: Hemorrhagic colitis
Bacteria: Shiga toxin-producing
Escherichia coli, including
O157:H7 and O157:NM
Type of Illness: Toxin-mediated infection
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Illness: Hemorrhagic colitis
(continued)
Bacteria: Shiga toxin-producing
Escherichia coli, including
O157:H7 and O157:NM
Type of Illness: Toxin-mediated infection
2 - 28
Basic Characteristics
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Unlike bacteria, they rely on a
living cell to reproduce
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Unlike bacteria, they do not
reproduce in food
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Some may survive freezing and cooking
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Can be transmitted from person to
person, from people to food, and people to
food-contact surfaces
Can contaminate both food and water supplies
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Caused By Viruses
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Hepatitis A
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Norwalk Virus Gastroenteritis
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Rotavirus Gastroenteritis
2 - 30
Illness: Hepatitis A
Virus: Hepatovirus or hepatitis A virus
Type of Illness: Infection
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Illness: Hepatitis A
(continued)
Virus: Hepatovirus or hepatitis A virus
Type of Illness: Infection
2 - 32
Illness: Norwalk Virus
Gastroenteritis
Virus: Norwalk and Norwalk-like viral agents
Type of Illness: Infection
2 - 33
Illness: Norwalk Virus
Gastroenteritis (continued)
Virus: Norwalk and Norwalk-like viral agents
Type of Illness: Infection
2 - 34
Basic Characteristics
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Living organisms that
need a host to survive
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Small, often microscopic
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Grow naturally in many animals and
can be transmitted to humans
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Can be killed by proper cooking
and freezing
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Pose a hazard to food and water
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Caused By Parasites
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Trichinosis
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Anisakiasis
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Giardiasis
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Toxoplasmosis
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Intestinal Cryptosporidiosis
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Cyclosporiasis
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Illness: Trichinosis
Parasite: Trichinella spiralis
Type of Illness: Infection
2 - 37
Illness: Trichinosis
(continued)
Parasite: Trichinella spiralis
Type of Illness: Infection
2 - 38
Illness: Anisakiasis
Parasite: Anisakis simplex
Type of Illness: Infection
2 - 39
Illness: Anisakiasis
(continued)
Parasite: Anisakis simplex
Type of Illness: Infection
2 - 40
Fungi
Commonly cause food spoilage
and sometimes illness
Fungi
Molds
Yeasts
Mushrooms
2 - 41
Basic Characteristics
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Spoil food and sometimes
cause illness
Grow well in sweet, acidic
food with low water activity
Freezing prevents or reduces
their growth, but does not
destroy them
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Some produce toxins called aflatoxins
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Pose a hazard to food
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Basic Characteristics
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Some spoil food rapidly
Grow well in sweet,
acidic food with low
water activity
May produce a smell or
taste of alcohol as they spoil food
May appear as a pink discoloration or
slime and may bubble
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Foodborne Infections
Result when a person eats food containing
pathogens, which then grow in the intestines
and cause illness
Foodborne Intoxications
Result when a person eats food containing toxins
that cause illness
Foodborne Toxin-Mediated Infections
Result when a person eats food containing
pathogens, which then produce illness-causing
toxins in the intestines
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What do microorganisms need to grow?
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