Download food poisoning - scienceresources

FOOD POISONING
High Risk Foods
High Risk Foods are those perishable foods which can support
the growth of harmful bacteria and are intended to be eaten
without further treatment such as cooking, which would destroy
such organisms. They include :





All cooked meat and poultry.
Cooked meat products including gravy, stock, and
roll/sandwich fillings.
Milk, cream, artificial cream, custards and dairy products.
Cooked eggs and products made with eggs, eg.
mayonnaise.
Shellfish and other seafood.
Cooked rice.
What is Food Poisoning?
Generally food poisoning results from contamination of food and
the subsequent growth of food poisoning micro-organisms.
How do Bacteria Contaminate Food?
Clean food can be contaminated by bacteria from:1. The people present in the workplace and their clothing.
2. Other food that is already contaminated.
3. Dirty kitchen or work premises and equipment.
4. Insects and vermin.
Sometimes, harmful bacteria pass directly from the source to high
risk food, but usually they rely on other things to transfer them to
food.
Common Food Poisoning Illnesses
Illness
Clostridium
perfringens
Contaminated Food Sources
Poultry meat and meat products, especially
stews, gravies and pies
Meat & meat products, especially poultry.
Salmonella
Custard, cream, milk & egg products, & salads.
Moist protein foods (meat, eggs and fish
Staphylococcus
products).
Meat & meat products, especially poultry.
Campylobacter
Water, and raw milk.
Processed meats & meat products, raw milk,
Listeria
seafood, poultry & veges etc (eg coleslaw).
Meat and meat products, especially pork mince
Yersinia
and tongue. Contaminated water, seafood and
raw milk.
Contaminated food and water, unpasteurised
Cryptosporidium
milk or fruit juices.
PREVENTION OF FOOD POISONING
In most cases of food poisoning a chain of events takes place,
and if we are to reduce the incidence of illness, this chain must be
broken.
The Food Poisoning Chain:
Food
Poisoning
Bacteria
Contaminate
High
Risk
Food
Given
Time
&
Warmth
Multiply
Then
infect
people
There are three main ways of
breaking the food poisoning
chain 1. Protecting food from
contamination.
2. Preventing any bacteria
present in the food from
multiplying.
3. Destroying those bacteria
that are present in the
food.
Relationship Between Temperature & the Growth &
Destruction of Bacteria
Each micro-organism has an optimum temperature where it grows
most rapidly and a maximum and minimum temperature at which
it will grow. Outside this range it will grow very slowly, or not at all.
pH
Most microbes prefer to live in a neutral environment around
pH 7. Yeasts, moulds & lactic acid bacteria are the most
capable of growth at low (acidic) pH.