ch8 food safety (microorganisms, characteristics, foodborne)

define foodborne pathogen

Virus, microorganism, or other substances that cause disease.

what is the pulsenet system

a national network of public health laboratories that per form a “fingerprinting” on bacteria that may be foodborne

safety of food is impacted by both ___________ and _________-

spoilage and contamination

define spoilage

Denotes unfitness for human consumption due to chemical or biological causes

define contamination

presence of harmful substances in food

• typically is categorized as biological, physical, or chemical

• Not always visible

what are the 4 criteria to ensure food is fit to eat

• The desired stage of development or maturity of the food

• Freedom from pollution at any stage in production and subsequent handling

• Freedom from objectionable chemical and physical changes resulting from action of food enzymes; activity of microbes, insects, and rodents; invasion of parasites; and damage from pressure, freezing, heating, or drying

• Freedom from microorganisms and parasites causing foodborne illnesses

define microorganisms

organisms too small to see so require microscope

-not all are harmful

define pathogens

Harmful microorganism that can cause illness or death.

• categorized as bacteria, viruses, parasites, fungi, and natural toxins

when does biological contamination occur

when harmful microorganisms contaminate food and cause foodborne illness

what are the most common foodborne agents (5)

Salmonella, Toxoplasma gondii, Listeria monoytogenes, Norovirus, and Campylobacter

F in FAT TOM (what it stands for and details)

Food- specifically carbohydrates and proteins

A in FAT TOM (what it stands for and details)

Acidity- a pH of 4.6 to 7.5 is ideal

T in FAT TOM (what it stands for and details)

Time- food should be in the temperature danger zone for limited amounts of time

T in FAT TOM (what it stands for and details)

Temperature- growth is best between 41°F and 135°F (5°C and 57°C)

O in FAT TOM (what it stands for and details)

Oxygen- some need oxygen, others do not

M in FAT TOM (what it stands for and details)

Moisture- water activity (Aw) of 0.85 or higher is ideal for growth

what is foodborne illness

disease transmitted to people through food

-2 or more people with same symptoms after eating same foods

who is highest risk for foodborne illness (3)

 elderly, preschool ages children, people with compromised immune system

define bacteria

Bacteria are microscopic, unicellular organisms of varying size and shape, including spherical, rod, and spiral

what are the most common bacteria to cause foodborne infections (4)

 Campylobacter, Nontyphoidal Salmonella, Staphylococcus aureus, and Escherichia coli O157:H7

what is the growth log of bacteria and its stages

lag phase, log phase, stationary phase, and death phase

lag phase

Lag phase- initial stage where, although bacterial cells exist, little to no growth occurs

log phase

Log phase- a period of rapid growth in a relatively short period of time

stationary phase

Stationary phase- the rate of growth is slowed and eventually stops as bacterial cells begin to die

death phase

Death phase - bacterial cells die more rapidly, new cells are created due to lack of nutrients and the excess waste the cells create

what types of foods are most supportive of bacterial growth

high protein or carbs foods

what are the 6 things that affect bacterial growth

• temp

• time

• pH

• respiration

• moisture

• natural inhibitors

define pH value

degree of foods acidity or alkalinity

best pH for growth

near neutral (slightly acidic, neutral, and slightly alkaline food materials)

define time/temperature control for safety food (TCS)

Food items that require temperature control because they are capable of supporting growth of pathogenic microorganisms or toxin formation

food that require TCS usually have what characteristics (4)

high protein, moisture, neutral or slight acidic,  and require time and temperature controls to prevent growth of microorganisms
- include products such as milk and dairy products, meat, poultry, pork, lamb, fish and shellfish, eggs, raw sprouts, baked potatoes, tofu, and sliced melons.

spores are what (what characteristics)

more resistant to high heat, low humidity, and other adverse conditions than are vegetative bacterial cells

They may remain dormant for long periods of time and germinate when conditions are favorable into new, sensitive, vegetative cells

define thermal death time

Time required at a specific temperature to kill a specified number of vegetative cells or spores

time and bacterial growth

need only a few hours to generate more than 4 million cells

-usually illness occurs in 4 hours

define aerobic and anaerobic bacteria

• Aerobic bacteria- Bacteria that need oxygen to grow.

• Anaerobic bacteria- Bacteria that reproduce without oxygen

what moisture do bacteria need to grow and reproduce

at least as of 0.85

define foodborne infection

 Caused by activity of large numbers of bacterial cells carried by the food into the gastrointestinal tract.

define foodborne intoxication

caused by toxins formed in the food prior to consumption

• Consumption of the toxins causes the illness

• Quick onset (as little as 2 hrs)

what are the bacteria (11)

• Salmonella

• Shigella

• Listeria monocytogenes

• Staphylococcus aureus

• Clostridium perfringens

• Bacillus cereus

• Clostridium botulinum

• Campylobacter jejuni

• Escherichia coli

• Vibrio parahaemolyticus, vibrio vulnificus

• Yersinia enterocolitica, Yersinia pseudotuberculosis

salmonella

• onset time

• duration

• symptoms

• source

• associated food

• is it spore former

• prevention

• onset time: 6-48 hours

• duration: 2-3 days

• symptoms: abdominal, pain, headache, nausea, vomiting, fever, diarrhea

• source: water, soil, domestic and wild animals, also humans, specially as carriers

• associated food: poultry and poultry salads, meat and meat products, milk, shell eggs egg custard and sauces, and other protein foods

• is it spore former: no

• prevention: avoids cross contamination, cook poultry to 165, cool cooked meats and poultry quickly, avoid fecal contamination from food handlers

shigella

• onset time

• duration

• symptoms

• source

• associated food

• is it spore former

• prevention

• onset time: 12-50 hours

• duration: undefined; depends on if treatment

• symptoms: abdominal pain, diarrhea, fever, chills, dehydration, vomiting

• source: human feces, flies

• associated food: potato, tuna, shrimp, turkey, macaroni salad, lettuce, moist and mixed foods, milk and milk products

• is it spore former: no

• prevention: avoid cross contamination, fecal contamination from handlers by having personal hygiene, use sanitary food and water sources, control flies, rapidly cool foods

listerila

• onset time

• duration

• symptoms

• source

• associated food

• is it spore former

• prevention

• onset time: 3-70 days

• duration: indefined; depends on treatmeant but has high fatality with immunocompromised

• symptoms: nausea, vomiting, headache, fever, chills, backacke, meningitis

• source: humans, domestic and wild animals, fowl, soil, water, mud

• associated food: unpasteruized milk and cheese, veggies, poultry and meat, seafood, prepared, chilled, RTE foods

• is it spore former: no

• prevention: use only pasteurized milk and dairy, cook to correct temp, avoid contamination, clean and sanitize surfaces

staphylococcus aureus

• onset time

• duration

• symptoms

• source

• associated food

• is it spore former

• prevention

• onset time: 1-6 hours

• duration: 1-2 days

• symptoms: nausea, diarrhea, vomit, dehydration

• source: humans, also animals

• associated food: reheated foods, ham and other meats, dairy products, custard, meat, egg, potato salad, cream filled pastries, other protein foods

• is it spore former: YES

• prevention: avoid contamination from bare hands, exclude sick food handlers, practice sanitary habits, proper heating, cooking, and refrigeration

clostridium perfringens

• onset time

• duration

• symptoms

• source

• associated food

• is it spore former

• prevention

• onset time: 8-22 hours

• duration: 24 hours, symptoms can last 2 weeks

• symptoms: abdominal pain and diarrhea

• source: humans (intestinal tract), animals and soil

• associated food: cooked poultry and meat that is improperly cooked, held, or cooled

• is it spore former: yes

• prevention: careful time and temp control in cooling and reheating

bacillus cereus

• onset time

• duration

• symptoms

• source

• associated food

• is it spore former

• prevention

• onset time: 1.2-5 hours, or 8-16 hours

• duration: 6-24 hours

• symptoms: nausea, vomiting, diarrhea, abdomial cramps

• source: soil, cereal crops

• associated food: rice and rice dishes, custards, seasoning, dry food mixes, spices, pudding, cereal products, sauces, veg dishes and meatloaf

• is it spore former: yes

• prevention: use careful time and temp control and quick chilling; proper reheating

clostridium botulinum

• onset time

• duration

• symptoms

• source

• associated food

• is it spore former

• prevention

• onset time: 12-36 hours

• duration: several days or a year

• symptoms: vertigo, visual disturbance, inability to swallow, respiratory paralysis

• source: soil and water

• associated food: improperly processed canned goods of low acid foods, garlic in oil products, grilled onions, stews, meat/poultry loafs

• is it spore former: yes

• prevention: do not use home canned products; use temp and time control; keep sous vide refrigerated; purchase garlic in oil in small quantities, cook red onion only on request, rapidly cool leftovers

campylobacter jejuni

• onset time

• duration

• symptoms

• source

• associated food

• is it spore former

• prevention

• onset time: 3-5 days

• duration: 1-4 days

• symptoms: diarrhea, fever, nausea, abdominal pain, headache

• source: domestic and wild animals

• associated food: raw veg, unpasteurized milk and dairy products, polutry, beef. pork, and lamb

• is it spore former: no

• preventionL avoid cross contamination and cook properly

Escherichia coli

• onset time

• duration

• symptoms

• source

• associated food

• is it spore former

• prevention

• onset time: 12-72 hours

• duration: 1-3 days

• symptoms: bloody diahrrea, severe abdominal pain, nausea, vomiting, diahrrhea, and ocassional fever

• source: humans, animals, particularly cattle

• associated food: raw and undercooked beef and other red meats, imported cheeses, unpasteurized milk, raw fin fish, cream pies, mashed potatoes, and other prepared foods

• is it spore former: no

• prevention: cook beef properly, avoid cross contamination, use food and water supplies, avoid fecal contamination from handlers

vibrio (parahaemolyticus and vulnificus)

• onset time

• duration

• symptoms

• source

• associated food

• is it spore former

• prevention

• onset time: 4-96 hours

• duration: 1-8 days

• symptoms: diarrhea, abdominal cramp, vomit, headache, fever chills

• source: fish and shell fish (mainly from gulf of Mexico)

• associated food: raw or improperly cooked oysters or shellfish from contaminated waters

• is it spore former: no

• prevention: avoid raw or undercooked seafood, purchase seafood from approved sources

Yersinia enterocolitica, pseudotuberculosis

• onset time

• duration

• symptoms

• source

• associated food

• is it spore former

• prevention

• onset time: 24-48 hours

• duration: days to weeks

• symptoms: abdomial pain, vomit, diahrrhea, headache

• source: soil, water, pigs, wild rodents

• associated food: raw and partially cooked meat (lamb, pork, beef), oysters, fish, raw milk

• is it spore former: no

• prevention: thoroughly cook foods, minimize cross contamination, properly clean and sanitize facilities

define virus

small pathogens that are not a complete cell

viruses cannot grow where

outside of host (so not cooked food)

types of viruses (3)

norovirus

hepatitis A

rotavirus

norovirus

• onset time

• duration

• symptoms

• source

• associated food

• is it spore former

• prevention

• onset time: 24-48 hours

• duration: 1-3 days

• symptoms: nausea, vomiting, diarrhea, abdominal pain, headache, and low grade fever

• source: humans, contaminated water

• associated food: raw veg, prepared salads, raw shellfish, water contaminated human feces

• is it spore former: no

• prevention: use safe water and water supplies, avoid fecal contamination from food handlers, cook foods well, purchase shellfish from reputable supplier

hepatitis A

• onset time

• duration

• symptoms

• source

• associated food

• is it spore former

• prevention

• onset time: 10-50 days

• duration: 1-2 weeks

• symptoms: sudden onset of fever, fatigue, nausea, headache, abdominal pain, jaundice

• source: humans, contaminated water and food

• associated food: water and shellfish, salads, ice, cold, cuts, fruits and juices, veg, milk and milk products

• is it spore former: no

• prevention: obtain shellfish from reputable source, prevent cross contamination with proper handwashing, use sanitary water, exclude food handlers who have Hepatitis A

rotavirus

• onset time

• duration

• symptoms

• source

• associated food

• is it spore former

• prevention

• onset time: 1-3 days

• duration: 4-8 days

• symptoms: abdominal pain, vomiting, diarrhea, mild fever

• source: humans, contaminated water

• associated food: water, ice, foods that do not have further cooking after handling such as salads, fruits, and raw veg

• is it spore former: no

• prevention: use sanitary water sources, prevent contamination by prper handwashing

define parasites

 are living organisms that need a host to survive

types of parasites (6)

richinae, Anisakis simplex, Cryptosporidium parvum, Cyclospora cayetanensis, Giardia duodenalis, Cyclospora cayetanensis.

trichinae

-effects of body

-foods

-prevention

• affects the muscles of the body and is caused by the Trichinae parasite

• undercooked meat from infected animals

• Wild animal meat is the primary sources of trichinella

• Pork should be cooked to an end temperature of 160°F to prevent

Anisakis simplex

-food

-illness name

-destroyed how

• raw seafood dishes, like sushi, sashimi, and ceviche, and undercooked fin fish

• results in an illness termed anisakiasis.

• destroyed by cooking or freezing

Cyclospora cayetanensis, Cryptosporidium parvum, Giardia duodenalis

-source

-spreadability

• feces of contaminated individuals or contaminated water

• Infected individuals can transmit the parasite to others

Cyclospora cayetanensis.

-common place where found

• microscopic parasite composed of a single cell

• often is found in people who live or travel in developing countries and consume contaminated water or fresh produce washed in contaminated water

 

what are fungi (the 3 types)

single and multicellular organisms such as molds, yeasts, and mushroom

define molds

multicellular fungi

mold

-size

-grow where (environment characteristics)

-temp

• larger than bacteria and more complex in structure

• grow on a wide range of substrates—moist or dry, acid or nonacid, high or low in salt or sugar.

• grow over a wide range of temperatures (optimum temperature is between 77°F and 86°F)

yeast is what

unicellular form of fungi

yeast

-causes what

-found in/ used for

• not known to cause foodborne illnesses, but may cause spoilage of sugar-containing foods

• n important role in the food industry, particularly in the fermentation or leavening of beer, wine, and bread

mushrooms

-safety

• Type of fungi

• Many forms are safe to eat, some are toxic and can cause foodborne illness if eaten

natural toxins define

biological contamination can occur from the microorganisms themselves or by the toxins produced from these microorganisms

natural toxins resistance

toxins cannot be killed by freezing, cooking, or curing--> PASSED TO HUMANS WHEN CONSUMED

histamine

-food

-causes what

Scombroid poisoning occurs when persons consume scombroid and related species of fish (tuna, mackerel, mahi mahi) that have been time/temperature abused and bacteria on the fish have produced high levels of histamine

Ciguatoxin, Saxitoxin, Brevetoxin, and Domoic Acid

-found in what, cause issue how

Many species of marine algae contain toxins--> enter fish and shellfish--> passed on to humans who consume the fish

Ciguatoxin

-food

Ciguatera fish poisoning occurs with the consumption of Ciguatoxin and is found in predatory tropical reef fish such as barracuda, grouper, jacks, and snapper who eat smaller fish who have consumed the algae toxin.

saxotoxin

-cause what

which causes paralytic shellfish poisoning

brevetoxin

-cause what

which causes neurotoxic shellfish poisoning

domoic acid

-causes what

amnesic shellfish poisoning, can be in shell fish (clams, mussels, oysters, scallops) from contaminated waters

mushroom toxin

-categories

-produced by

-destroyal

-symptoms

• four categories of mushroom toxins: protoplasmic poisons (amanitin, gyromitrin, orellanine), neurotoxins (ibotenic acid, muscimol, psilocybin), gastrointestinal irritants, and disulfiram-like toxins

• produced naturally by a variety of types of mushrooms.

• cannot be destroyed by cooking or freezing

• can cause gastrointestinal distress, neurological impairment, organ failure, and even death

define prions

(PROteinaceous INfectious particle)

• small glycosylated protein molecules found in brain cell membrane

  • Prion diseases, often termed transmissible spongiform encephalopathy (TSE), are infectious diseases of the brain that can occur in both animals and humans

prions and heat

Prions are extremely resistant to heat!!

effects of prions in body

the disease course in humans includes behavioral changes, ataxia, progressive dementia, and death