If you buy tomatoes from John Banscher at his farm stand in New Jersey, he will recommend keeping them out of the fridge or they will lose some of their taste.
Now US scientists have figured out why: because some of their genes chill out, according to a study that might help solve that problem.
Cooling tomatoes below 12C stops them making some of the substances that contribute to their taste, according to researchers who dug into the genetic roots of the problem.
That robs the fruit of flavour, whether it happens in a home refrigerator or in cold storage before the produce reaches the grocery shelf, they said.
With the new detailed knowledge of how that happens, "maybe we can breed tomatoes to change that", said researcher Denise Tieman of the University of Florida.
She and colleagues there, in China and at Cornell University in Ithaca, New York, report their findings in a paper published by the Proceedings of the National Academy of Sciences.
They showed that after seven days of storage at 4C, tomatoes lost some of their supply of substances that produce their characteristic aroma, which is a key part of their flavour.
Three days of sitting at room temperature did not remedy that, and a taste test by 76 people confirmed the chilled tomatoes were not as good as fresh fruit.
Tomatoes stored for just one or three days did not lose their aroma substances.
Further research showed the prolonged chilling reduced the activity of certain genes that make those compounds, Tieman said.
Her lab was looking at the possibility of breeding tomatoes that do not lose flavour in the cold, she said.
In the meantime, "just leave them out on the counter or leave them in a shaded area, something like that", said Banscher.
"A tomato has a decent shelf life."
