Download Food hygiene and handling

Food Hygiene and Handling
CROSS-CONTAMINATION
AND
FOOD POISONING
Cross-contamination
 Cross-contamination can be caused by people
placing food items next to each other without
covering them correctly, handling food with utensils
that have touched other food items, handling foods
without changing gloves or washing hands, or
placing foods on surfaces that have not been cleaned
after the previous task. Cross-contamination can be
avoided by following hygienic food handling and
food storage procedures.
Cross-contamination cont..
 The most common result of cross-contamination is
food poisoning. The symptoms may include nausea,
vomiting, stomach cramps and diarrhoea. If they are
severe, bacteria may enter the bloodstream and be
carried to other organs in the body. This can be fatal,
especially for very young children, the elderly and
people with significant health problems.
Cross-contamination
Food poisoning
 If excellent hygiene and environmental practices are
not maintained, there is a risk of food contamination
as well as food poisoning.
The causes of contamination may be:
The formation of toxins when bacterial growth is so high that cells
change to toxins that are resistant to heat or cold
 Eating naturally poisonous foods
 Eating obviously spoiled foods
 Incorrect storage and/or handling procedures

Food poisoning may be categorised under three main
types.
Chemical poisoning of food
 This occurs when food becomes contaminated with
chemicals, such as cleaning and sanitising chemicals,
as well as pesticides and insecticides
Physical poisoning of food
 This occurs when food becomes contaminated with
items such as glass shards, metal shavings, dust and
wooden splinters. It also occurs when foreign objects
fall or are mixed into food during cooking or
handling. Examples include:
Pests or insects
 Parts of equipment
 Scraps of packaging
 Pollutants, like dust and dirt

Biological poisoning of food
 This occurs when either the food itself is poisonous,
or by eating a food that has been contaminated by
microbes (virus, mould, bacteria). The most common
cause of microbial food poisoning are bacteria.
 The conditions that favour bacterial growth include:
Oxygen
 pH level – acid or alkaline
 Food
 Water
 Correct temperature
 Time

Danger zone
Staphylococcus aureus
 Symptom:
Nausea, diarrhoea, vomiting and severe stomach cramps
 Develops 1-8hrs after eating and last for 1-2 days

 Source:
High protein foods (milk, dairy, meat poultry, seafood and
eggs), sauces and gravies
 Contact with skin disorders, saliva and nasal droppings

 Prevention:
Killed easily by heat
 Cool food rapidly

Clostridium perfringens
 Symptom:
Nausea, diarrhoea and severe stomach cramps
 Develops 8-24hrs after eating and last for 1-2 days

 Source:
Dirt and dust
 Faeces
 Unwashed vegies
 Raw meat

 Prevention:
Killed easily by heat
 Wash vegetables well

Salmonella
 Symptom:
Nausea, diarrhoea, vomiting and severe stomach cramps
 Develops 1-8hrs after eating and last for 1-2 days

 Source:
Raw meat and seafood
 Milk
 Eggs
 Raw salads
 Faeces

 Prevention:
Killed easily by heat
 Ensure poultry is ALWAYS cooked thoroughly

Listeria
 Symptom:
Flu-like symptoms
 Particularly dangerous to pregnant women

 Source:
Milk
 Cheese
 Processed meats and meat products
 Pre-prepared foods like salads

 Prevention:
Follow use-by dates
 Pregnant women avoid risky foods

Clostridium botulism
 Symptom:
Nausea, diarrhoea, vomiting, headaches and constipation
 Develops 2-7 days after eating
 Can be fatal

 Source:
Seafood
 Dirt and dust

 Prevention:
Purchase seafood from reputable sources
 Do not use food bulging or dented cans

Camphylobacteria
 Symptom:

Nausea, diarrhoea, vomiting and severe stomach cramps
 Source:
Soil
 Insects
 Raw poultry and meat
 Milk and dairy products

 Prevention:
Wash all vegetables well
 Ensure poultry is ALWAYS cooked thoroughly
