THE COLD truth about most household fridges is they are operating at the wrong temperature and leaving people at risk of food poisoning, a study has revealed.

An investigation by BBC One’s Rip Off Britain: Food found more than 90 per cent of fridges it tested were at above the recommended level of between three and five degrees celsius.

Anything higher than that could lead to a rapid increase in bacteria growing on food. In warm conditions one thousand germs can become one million in two hours.

Dr Ellen Evans at Cardiff Metropolitan University, whose research was used in the show, said opening and closing the fridge frequently could significantly affect the temperature for a long period. One fridge tested did not return to a safe temperature until 18 hours later.

She said: “It is really concerning the vast majority of fridges are at higher than safe temperatures.”

She recorded the temperature of 43 domestic fridges for six days and the impact opening and closing had on the thermometer.

In 39 of the fridges, temperatures were above five degrees, with some as high as 17.9C.

Dr Evans said: “Having the fridge at an unsafe temperature significantly increases the growth of bacteria, and could cause somebody to become unwell.”

She also spiked foods with the listeria bacteria to see how quickly it increased. At 7.5C it multiplied thousands of times over six days.

Listeria, which has symptoms like the flu, can be fatal. It can also seriously affect vulnerable people, such as those with weakened immune systems, people with cancer, pregnant women, newborn babies, children and the elderly. The bacteria is killed in cooking.

Pam, who lives in Cardiff, discovered during the show the temperature on the top shelf of her fridge reached 12C, while the middle shelf was recorded at below 5C for just 45 per cent of the time.

The study found no relationship between the age or style of the fridge and how well it worked.

Dr Evans added: “There’s no need to rush out and buy a new fridge, instead use a fridge thermometer. They are widely available and cheap to buy and that will tell you whether your fridge is the correct temperature.”

Gloria Hunniford, the show’s presenter, said: “Fridge thermometers are quite inexpensive. I can’t understand why everyone doesn’t have them installed.”

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