Researchers warn salmonella lurks in many foods
By Nicola Menke, dpa
October 30, 2012, 12:13 am TWN
Berlin--That noodle salad drenched in mayonnaise and left on the table from the party the night before. It may look enticing when you wake up, but don't touch it.
These are precisely the circumstances in which salmonella, the most common cause of food poisoning and diarrhea, thrives. A few hours out of the fridge are long enough for the bacteria, which are widespread in nature, to multiply.
Humans generally take in salmonella bacteria through the consumption of contaminated foods. The salmonella serotype most common in Europe, Salmonella enteritidis, is often passed on through inadequately cooked eggs or through foods containing raw egg, such as mayonnaise.
These present a particular hazard, according to Petra Dersch, a German professor of biology and an expert on the spread of infections.
Raw or partly cooked meat is another source, as well as seafood and fish. Salmonella infection caused by fruit, vegetables or other vegetable products like tea is rare, but cannot be excluded.
Experts have difficulty in assessing the true rate of infection, as many who become infected never see a doctor. The rate of infection rises in the warm summer months, which provide a favorable environment for the bacteria, especially if food is not properly refrigerated.
Nevertheless it is possible for outbreaks to occur outside the summer months, such as when contaminated foods come onto the market, or as a result of inadequate kitchen hygiene in hospitals, homes for the aged or universities.
Regular washing of the hands is essential in order to combat salmonella, not merely after using the lavatory, but also when preparing or eating food and when handling raw animal products.
Dersch lays down a few other basic rules. "Foods such as poultry and eggs, as potential salmonella carriers, should always be cooked through properly," she says.
Freshly prepared food should not be kept warm for too long, as this causes the bacteria to multiply, and raw and pre-prepared foods need to be kept adequately refrigerated, she says.
Cross-contamination, for example from raw meat to vegetables, should also be avoided. "To prevent this, raw and pre-prepared food should be kept and prepared separately," according to Rohtraud Pichner, a German nutritionist.