麻豆传媒

I LOVE raw oysters, so hoped to write a column saying there is no need to worry about food poisoning. When I looked into it, though, I found cause for concern. But there are safe ways to enjoy delicious oysters.

Folklore has it that oysters can be eaten in any month with an 鈥渞鈥� in it 鈥� in other words, avoiding the summer months, when they spawn. This discernment may date back to ancient times. By measuring parasitic snails in oyster shells, a , US, found that ancient people mostly harvested oysters in the autumn, winter and spring.

During the spawning season, oysters convert their resources into sperm or eggs, which renders them less palatable. People may also have avoided taking oysters in summer to allow populations to recover.

Nowadays, farmed oysters are available and good to eat all year round and are among the most sustainable seafoods. Since the 1980s, many farmed oysters have been . These oysters grow faster than natural oysters and remain firm and plump in the summer.

As filter-feeders, oysters can pick up pathogens lurking in the water. To reduce this risk, they are usually kept in clean water for 42 hours after harvesting in the UK, a process called depuration.

Sadly, this isn鈥檛 completely effective 鈥� particularly with respect to norovirus, one of the most common causes of gastroenteritis. A 2017 . Just 10 copies are thought to constitute an infectious dose.

In the UK, about , usually raw oysters. Given that more than 13 million oyster meals are served each year, you might consider this a low risk. But .

Fortunately, cooked oysters are delicious too. The simplest method is to oven cook oysters at 220掳C for 10 minutes. Heat will cause the shell to open, so place them on a wire rack or a bed of salt to stabilise them, so the juice doesn鈥檛 leak out. Once cool enough to handle, use a knife to gently separate the oyster from the shell. To serve, spoon on some melted butter with garlic, hot sauce and lemon juice.

Champagne is another traditional accompaniment to oysters, and a . Oysters and champagne contain compounds that activate umami taste receptors: glutamate from dead yeast cells in champagne and nucleotides in the oyster muscles. Combined, they create a stronger perception of umami than either does on its own.

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