You may want to think twice before grabbing that doggy bag.
A microbiologist is sharing the alarming reason she won’t go near leftovers, barbecues or oysters, warning of the dangers of common practices that could lead to food poisoning, which strikes more than 47 million Americans every year.
Primrose Freestone, a senior lecturer in clinical biology at the University of Leicester, says she rarely eats alfresco, “as the risk of food poisoning goes up when food is taken outdoors.”
Freestone told The Conversation that eating outdoors can attract flies, wasps and ants which can transfer dangerous bacteria — such as E coli, salmonella and listeria — to the food.
Eating at barbecues and picnics where food has been sitting out, she said, can also allow germs to flourish and potentially make the consumer ill.
The same is true for buffets, and she maintains a “two-hour catering rule,” meaning that perishable food is unsafe to eat within two hours of sitting out if it is not covered nor refrigerated.
“The problem is buffets tend to be laid out before you arrive, so it is difficult to tell if the platters of cooked meat, seafood, salads, desserts and appetizingly arranged fruit and vegetables will have been sitting for more than two hours when you come to eat them,” she told the outlet.
The two-hour time limit also applies to doggy bags or leftovers when dining out, as the remaining eats have “usually exceeded the two-hour time limit” before making the trek back to your refrigerator.
Even when it comes to hot food buffets, Freestone’s rule of thumb is to avoid lukewarm bites, as bacteria flourishes between 40°F and 140°F, known as the “Danger Zone.”
Then, there’s the issue of cleanliness — buffet-style settings allow uncovered meals to become potentially contaminated by the coughs and sneezes of other diners.
“Even indoors, one must consider contamination by insects, such as flies or wasps, settling on the uncovered food,” Freestone said. “Also, germs may be deposited from the air, which is rich in bacteria, fungi and viruses.”
Among the foods she’ll never touch are raw oysters and bagged salad mixes.
“This is because oysters are filter feeders and can concentrate germs, such as vibrio and norovirus, in their tissue,” she said.
According to the Centers for Disease Control and Prevention, 80,000 people contract vibrio and 100 die from it in the US every year. A vibrio-containing oyster won’t taste, smell or look any different than a normal oyster, so the only way to eliminate the bacteria is to thoroughly cook the shellfish.
Freestone claimed that bagged salad mixes could also be contaminated with harmful pathogens that thrive when feeding off the leaf juices.
“For those salad lovers alarmed by this information, most bagged salads are safe if stored refrigerated, washed well before use (even ready-to-eat salad should be washed) and eaten as soon as possible after buying it,” she advised.
Freestone also swears by a “list of dos and don’ts” in cooking — the first being regularly checking expiration dates, tossing items with swollen packages and not consuming food that looks or smells different than expected.
“I never use the same chopping boards for raw and cooked foods, and washing my hands before and after handling food is instinctual,” she said.
Her No. 1 “never do,” however, is reheating cooked rice — because it often contains bacillus cereus, a bacteria that produces toxins that can cause vomiting and diarrhea.
“Although the bacillus cells are killed by cooking, the spores survive,” she explained. “If the rice is left to cool and sit at room temperature, the spores grow into bacteria, which will increase in numbers quickly as rice is a good Bacillus culture medium when at room temperature.”