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At camp, you will not have the luxury of fridge freezers, microwaves and ovens to help you keep and prepare food so extra care must be taken and water for washing hands always placed at convenient places. When Cubs or Scouts are doing the cooking, please give discrete supervision until you can be sure they know and are following the basic rules of hygiene.
The following is one of many true stories investigated by the Department of Public Health.
A lady had prepared a cold buffet for her daughter's birthday party which was to be attended by many of her school friends. Because the food had been prepared a day in advance, it was kept in the refrigerator until a couple of hours before the party began. The lady had also removed a joint of frozen pork from the freezer and had put it on the top shelf of the fridge (on a shallow plate) to defrost. The liquid from the defrosting meat soon filled the shallow plate and started to drip onto the food below. A couple of hours before the party, the buffet food was taken out of the fridge and put on a table to enable it to warm up to room temperature.
Within a few hours of the food being eaten, every child that had attended the party was being treated in hospital for varying degrees of Salmonella food poisoning.
All the conditions necessary for bacterial growth bad been present:
 | A source of bacteria: The frozen pork. |
| Warmth: Taken from the fridge and put in a warm room. |
| Food & Moisture: The trifle contained custard and fresh cream. |
| Time: Two hours to enable the bacteria to multiply |
Food hygiene means more than just cleanliness, it involves all practices involved in:
- Protecting food from contamination, including harmful bacteria, poisons and foreign bodies.
- Preventing any bacteria present multiplying to an extent which would result in illness or food spoilage.
- Destroying any harmful bacteria in the food by thorough cooking.
Food poisoning
Food poisoning is an unpleasant illness which usually occurs within 1 to 36 hours of eating contaminated or poisonous food. Symptoms normally last from 1 to 7 days and include one or more of the following:
| Abdominal pain; |
| Diarrhea; |
| Vomiting and Nausea. |
Food poisoning may be caused by:
| Bacteria or their toxins; |
| Viruses; |
| Chemicals such as weed killers and insecticides; |
| Metals such as lead, copper and mercury; |
| Poisonous plants such as deadly nightshade and toadstools: |
Bacterial food poisoning is by far the commonest and in some instances, such as the very young and the elderly, may result in death.
Common food poisoning bacteria. |
% of reported cases. |
| Salmonella | 80% to 90% (Found in a majority of meat and dairy products) |
| Clostridium | 5% to 15% (Usually found in the soil and on root vegetable skins) |
| Staphylococcus | 1% to 4% (Usually found in the human body) |
High risk foods
High risk foods are usually considered as those which support the multiplication of harmful bacteria and are intended for consumption without treatment such as cooking, which would destroy such organisms. These foods are usually proteins and require refrigerated storage. They must always be kept separate from raw foods.
Examples include:
- All cooked meats and poultry;
- Cooked meat products including gravy and stock;
- Milk, cream, artificial cream, custards and dairy products;
- Cooked eggs and products made from eggs;
- Shellfish and other seafood;
- Cooked rice:
All of the above are frequently implicated in outbreaks of food poisoning, especially poultry and cooked meat.
Unfortunately, contaminated food usually looks, tastes and smells completely normal.
Bacteria
These are microscopic organisms which are found everywhere, including on and in man, on food, in water, soil and air. Most bacteria are harmless and some are essential e.g. for cheese and yogurt making. However a small number of bacteria cause food spoilage and some, known as pathogens; are responsible for causing illness.
Requirements for Bacterial Growth.
Bacteria responsible for causing food poisoning need the following conditions to enable them to grow.
Warmth
The best temperature for the growth of food poisoning bacteria is 37°C (body temperature), although they can grow quite quickly between 20°C and 50°C. To prevent their growth we must ensure that the temperature of food is kept below 5°C or above 63°C. The temperature range 5°C to 63°C is often referred to as the "danger zone".
Food and Moisture
High protein foods are preferred, especially meat, poultry and dairy produce. Dried foods are not ideal growing mediums until moisture (water or milk) are added. Foods which do not support bacterial growth are those containing high concentrations of sugar, salt, acid or other preservatives.
Time
Given the right conditions of food, moisture and warmth, some bacteria can divide into two every 10 minutes. This process is known as binary fission. If there is sufficient time, a few bacteria can multiply to such an extent that there are enough present to cause food poisoning. For this reason it is essential that high risk foods are not left in the danger zone for longer than is absolutely necessary.
IN 3 HOURS & 20 MINUTES (GIVEN THE RIGHT CONDITIONS) 1 SINGLE BACTERIA CAN BECOME 1,000,000+.
FOOD CONTAMINATION
Sources of food poisoning bacteria:
(1) THE PERSON: People commonly harbor food poisoning bacteria in the nose, mouth, intestines and on the skin. Food may be contaminated directly by the hands or by sneezing and coughing.
(2) RAW FOOD: Raw food is particularly hazardous, especially -red meat, poultry (up to 80% of frozen birds may carry salmonella), untreated milk, eggs and shellfish. Raw food should always be kept separate from high risk food. The liquid from defrosting foods, especially frozen poultry, must not be allowed to contaminate other foods or wiping cloths which may be used later to wipe down work surfaces. Soil harbors harmful bacteria so care must be taken with raw vegetables.
(3) INSECTS: Several insects may transmit food poisoning bacteria to food. Flies and cockroaches present the greatest hazard because of their feeding habits and the sites which they visit Careless use of insecticides may result in dead insects ending up in the food.
(4) RODENTS: Contamination can occur from droppings, urine, hair and surfaces they have walked over. Any food which has been gnawed must be destroyed.
(5) DUST: There are always large numbers of bacteria in dust and floating about in the air. Open food should always be kept covered.
(6) REFUSE & WASTE: Waste and unfit food must be thrown away as soon as possible and not be allowed to accumulate near food ready for preparation.
Traditional
Training Handbook
©2003 Baden-Powell Scouts Association
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