Salmonella and E.coli are two of the most common strains of bacteria that cause what is generally known as ‘food poisoning’. It is important to understand the differences between these two strains of bacteria – they grow and spread in different ways, and it is even more important to understand the ways in which their production and spread can be avoided.
Salmonella is the most commonly known brand of bacteria. It can grow effectively in unpasturised milk, eggs, meat and poultry.
Salmonella multiplies if food is not cooked thoroughly, or is not chilled to a suitable temperature. Infection spreads by human contact, so strict hygiene routines are essential in food preparation areas, not only in food production and storage, but also in personal hygiene – frequently and through hand-washing helps to cut down the spread of the bacteria.
Symptoms of infection include nausea, stomach cramps, and blood in faeces, often with diarrhoea. These reactions normally occur between six and seventy-two hours of infection. There is no cure of the infection itself, which simply passes through the body naturally. An infected person needs to rest and take in plenty of fluids to avoid dehydration. Although unpleasant, salmonella infection is rarely serious, and only one per cent of infections are fatal.
E.coli spreads through similar breeding in undercooked or under-chilled foods, but it can also be contracted by contact with infected animals, or land that has contained infected animal faeces.
Again, appropriate cooking and hygiene routines can minimise the effect of spreading the bacteria. Eating undercooked beef causes the most common spread of E.coli. The bacteria lives in the digestive system of cattle without harm, but the slaughtering process releases the bacteria into the meat, and on into the human digestive system if the meat is not stored and cooked properly.
Symptoms of infection include sudden severe stomach cramps and frequent passing of watery diarrhoea. After twenty-four hours, the diarrhoea turns bright red as the bacteria irritates the intestine and creates sores. This diarrhoea can last between two and five days. Sufferers should avoid any medication to stop the diarrhoea as this prevents the body from processing the bacteria naturally through normal waste production. Bed rest and fluid intake are the standard responses, and again, E.coli infection is rarely serious or fatal, although children and old people should be monitored carefully.
Avoiding Salmonella And E.coli
Correct food preparation routines are essential to prevent the spread of these bacteria, and the following check list will minimise the risk of transmission.
- Keep raw meat separate from all other foods. It is often the source of bacteria, and can spread to anything it touches including other food, chopping boards, utensils, storage containers and so on.
- Never prepare any other food on a board on which you have placed raw meat without washing it thoroughly first. This applies to all utensils, and of course, your hands, which you should wash frequently for at least thirty seconds, using soap and hot water.
- Cover raw meat and store it in the bottom of the fridge to avoid any blood or juices dripping on other stored food.
Testing For Thorough Cooking Of Food
Because Salmonella and E.coli bacteria multiply and spread via improperly cooked food, you should always check that what you eat has been cooked properly, even if you have cooked it yourself. The following checks advise techniques you should use.
- Always cut into the centre of a burger, sausage, portion of meat etc. and check that there is no pink meat left, and that the meat is piping hot (issuing steam) throughout.
- If you are checking a chicken or whole bird, pierce the thickest part of the leg – between the thigh and the drumstick with a clean skewer or knife, and check the juices that run out. They should be clear, with no pink or red blood traces.
- Kidney, liver and similar should be checked by cutting into the middle to ensure that the portion is piping hot.
It is safe to eat rare cuts of meat, provided they have been ‘sealed’ before cooking – this is usually done by quick frying over a high heat. This will kill any bacteria on the outside of the meat. To ensure that your meat has been sealed properly, check it has changed colour over its whole surface area before you start to eat.
Remember, whole cuts of meat are safe to eat rare, but rolled joints – pieces of more than one cut, together with pork, poultry, and kebabs should not be eaten rare.
Following these rules for the preparation, storage, cooking and checking of meat will ensure that you can virtually eliminate the risks of infection from Salmonella and E.coli for yourself and your family.