I'm a microbiologist - this is the common dining mistake people make that's causing crippling illness

Daily Mail​

22-07-2025

A food poisoning expert has warned that buffets are a 'hotspot for illness' because of common hygiene mistakes.
Cross contamination and poor temperature control are the leading cause of food related illness during the dining experience, according to the microbiologist.
Dr Kimon-Andreas Karatzas, Associate Professor of Food Microbiology at the University of Reading said: 'Without proper precautions, [buffets] can also pose serious food safety risks.
'One of the main food safety challenges at buffets is temperature control. Harmful bacteria multiply rapidly in what experts call the "danger zone".'
The high risk zone is the temperature range between 8°C and 63°C. If food sits within this range for too long, it becomes an ideal breeding ground for microbes.
'Unfortunately, in busy all-you-can-eat environments, it's common for staff to top up half-empty trays instead of replacing them.
'While this may reduce food waste, it increases the likelihood of contamination, especially during high-traffic service times,' says Dr Karatzas, writing in the Conversation.
'Without strict hygiene protocols in place, even small lapses in temperature control can lead to widespread illness.'
The expert highlights that there are three main bacteria to be wary of at buffets.
The first is salmonella, which is often found in under-cooked poultry, eggs, and dairy products. He warns that it can cause diarrhoea, fever, and abdominal cramps, and it spreads easily if hot food is not kept at a safe temperature.
He also notes that 'e. coli, typically linked to under-cooked beef and raw vegetables, can cause severe gastrointestinal illness and, in some cases, lead to kidney failure.'
Finally, a bacteria often found in soft cheeses, pâté, and pre-packed sandwiches — listeria monocytogenes — can be a risk to people with weakened immune systems like pregnant women.
'In many buffet settings, food is left sitting out for extended periods – sometimes in ambient room temperatures, and sometimes without adequate heating or refrigeration equipment. This allows bacteria to flourish,' says Dr Karatzas.
The expert also warns that cross contamination is a serious risk at buffets.
'If just one dish becomes contaminated—say, with under-cooked meat juices or bacteria from unwashed hands—they can spread to other foods, affecting many people,' says Dr Karatzas.
'Sneezes over platters and untrained customers handling food directly all increase the risk. Even something as simple as using the same spoon for multiple dishes can be enough to transfer bacteria.
'With many hands touching the same utensils and food being moved or mixed between containers, even a well-run buffet can become a hazard zone as it is difficult to monitor and control that all customers abide to food safety rules.'
The expert warns that common cross contamination puts diners with allergies at greater risk.
'Cross-contamination means that allergen-free foods can become unsafe through even minimal contact with allergenic ingredients,' says Dr Karatzas. 'Putting allergic diners at greater risk.'
Official statistics show that around 2.4 million people in the UK get food poisoning every year.
The Food Standards Agency (FSA) estimates that there are closer to 18 million cases of food poisoning in the UK each year — almost one in four people.
Food poisoning is rarely serious and usually gets better within a week.
Common symptoms include feeling sick, diarrhoea, tummy pain, a high temperature and feeling generally unwell.
To avoid these uncomfortable symptoms the microbiologist recommends that when at a buffet clean utensils should be available for each item, check dishes should be steaming hot or chilled, not lukewarm and diners should wash their hands before serving themselves.