Topic 3: Part B Flashcards
Microbial food poisoning (food borne illness) stats
- 4 million cases every year in Canada
- 77% of cases occur in food service establishments
- 20% of cases occur in the home
- 3% of cases occur in food processing
Major source of contamination of food is..
food handlers
3 hazards
- physical
- chemical
- biological
Physical hazards
- metals
- broken glass
- stones
- jewelry
- wood
Chemical hazards
- sanitizer
- pesticides
- paint
- excess food additives
- natural toxins
Biological hazards
- molds
- bacteria
- viruses
- parasites
Food borne illness can be causes by ..
infection or intoxication
Infection
- multiplies and infects tissues in the body
- imbalance of osmotic pressure occurs resulting in diarrhea
- damaged cells in intestinal tract signal the brain to trigger vomiting
- fevers occur
- ex: salmonella, shigella
Onset of symptoms for infection take ..
12 hrs to 2 days.
Shigella
typical food illness starts 1-2 days
Intoxication
- produce toxins as they multiply which cause harm to tissues
- toxins grow if food isn’t stored properly
- toxins can cause damage to cells that line the intestinal tract, and can travel to kidneys and damage there.
- ex: staphylococcus aureus, clostridium botulinum
Onset of symptoms of intoxication take..
a few hours, very fast.
Staphylococcus aureus is..
anaerobic and doesn’t require oxygen
Symptoms of intoxication
- Headache
- Nausea
- Vomiting
- Dehydration
- Abdominal pain
- Diarrhea
- Fatigue
- Fever
FATTOM
- F: food (high protein)
- A: acid
- T: temp
- T: time (2-4 hrs outside fridge)
- O: oxygen
- M: moisture
Danger zone for food temperature
4C to 100C
Salmonella
- found in human and animal feces
- enter food via contaminated water, cutting boards, contaminated meat products, cracked eggs, bits of feces in food
- onset symptoms 1-2 days duration 1-7 days
- can be fatal to infants, elderly or sick
Leading cause of food borne illness in North America
salmonella 2-4 million cases.
Symptoms of salmonella
- nausea
- headache
- diarrhea
- abdominal pain
- chills
- fever
- vomiting
- dehydration
- long term complications: severe arthritic symptoms
Typical food involved w salmonella
- raw/undercooked eggs
- meat (especially poultry)
- raw milk
- raw sprouts/seeds
- unwashed raw fruits/veggies
Prevention of salmonella
- cook eggs and poultry thoroughly
- pasteurize milk/juice
- irradiate chicken
- avoid cross contamination
- proper hand washing
- appropriate kitchen clean up
- use of disinfectant cleaners/ sanitizers (eg. bleach).
Staphylococcus aureus
- common bacterium present in nasal passages, throats, on the hair and skin of 30-40% of healthy people and animals
- responsible for 20-40% of all cases of food poisoning
- food handlers usually main source of outbreaks
- toxin produced by the bacteria that actually causes illness
Staph. Aureus has ability to….
make 7 different toxins. toxin is what causes illness
Staph. Aureus multiply rapidly at…
room temp to produce toxins that are resistant to heat and cannot be destroyed by cooking
Staph. Aureus bacteria itself can be killed by..
very high heat (121 in moist heat for 15 min, 170 dry heat for an hour) and a sanitizing agent
Staph. Aureus toxins produced though are..
heat resistant and stable at boiling temp so won’t be killed by boiling food
Onset and symptoms of Staph. Aureus
- onset 30min-8 hrs
- duration 1-2 days
- symptoms: nausea, diarrhea, cramps, dehydration
- severe cases: headache, muscle cramping, blood pressure change
- rarely fatal
Susceptible foods for Staph. Aureus
- meats
- seafood
- poultry
- cheese
- egg products (eg. custard)
- whipped butter
- salads/sandwich fillings with mayonnaise (eg. tuna, egg, potato, macaroni, chicken)
- bakery products (eg. cream-filled pastries, chocolate éclairs, milk/milk products)
Presentation of Staph. Aureus
do not allow infected persons prepare food; thorough heating and cooling of food; good sanitation
Escheichia Coli Strain (0156:h7)
- newer strain
- onset 12-18 hrs
- duration up to 8 days
- symptoms: nausea, vomitting, watery/bloody diarrhea, abdominal pain, dehydration
- 2-7% causes lead to hemolytic uremic syndrome and kidney failure
- hamburger disease
Typical foods where you get E. Coli
- raw undercooked meat
- raw milk
- unpasteurized fruit juices
Prevention of E. Coli
cook meat thoroughly especially ground meat. pasteurize milk and fruit juice. avoid cross contamination. only lives on surface of meat
Clostridium Botulinum
- anaerobic bacteria present in soil, water, plants, intestinal tract of animals/fish
- produce most powerful natural toxin that blocks nerve function
- intoxication not infection.
Typical foods for Clostridium Botulinum
- found in improperly home canned or commercially canned foods, especially low acid home canned foods. (leaky, bulging, dented, broken cans)
- found in items tightly sealed (flavoured oils, canned goods)
- honey has extreme low doses of this
Symptoms and onset of clostridium botulinum
- 12 to 72 hrs
- symptoms: double vision, unable to swallow, speech difficulty, and progressive paralysis
- long term: fatigue shortness breath. can be fatal and antitoxin is required
Prevention of clostridium botulinum
sterilize canned foods, cook/reheat food properly (spores are killed at 120C for 10 min)
