Reporting Jason DeRusha
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MINNEAPOLIS (WCCO) — Some things are obvious: meat, eggs and milk go in the refrigerator. Other things are controversial: Tomatoes, bread, apples and peanut butter. So, the question is: To refrigerate or not to refrigerate?
“If you like a fully-developed flavor in a tomato, you definitely want to keep it out of the fridge,” said Francisco Diez-Gonzales, a Food Science Professor at the University of Minnesota.
According to Diez-Gonzales, the fridge slows the natural reactions that make a tomato ripe, and stops the flavor short of full potential. Refrigerating does slightly extend the life of a tomato, but comes with a cost.
Researchers say apples soften twice as fast at 40 degrees than at 32. So, put them in the fridge. Diaz-Gonzales said that apples are already at their full flavor when they’re picked, so refrigerating doesn’t come at any cost.
Bread will last almost a week longer if you refrigerate it, but it won’t taste the same.
“Basically, the starch in the bread is going to start changing the structure. That may give you a different taste and texture to the bread,” said Diaz-Gonzales.
Dietician Sue Moores tells us that bread usually lasts 3 to 7 days on the counter, and 1 to 2 weeks in the refrigerator.
It’s longer life, again, at a cost.
Ketchup is tricky, said Diaz-Gonzales, as it’s perfectly safe out of the fridge.
“It’s very shelf stable because it has a lot of vinegar,” he said, a natural acidity that keeps it from going bad.
But that depends on storage conditions: if your house is warm – it can affect the taste, especially with the plastic bottles that aren’t sealed as tightly as the glass bottles are.
Unless you open one jar and take 6 months to eat it, peanut butter can sit out on the counter. According to Smucker’s, its peanut butter is “shelf-stable.”
Some natural peanut butters recommend refrigeration, but when the label says “refrigerate after opening,” that is typically about quality control and taste rather than safety. Some peanut oils may require refrigeration, according to Diaz-Gonzales.
Syrup and honey should also stay out of the fridge, because the cool temperatures can cause the concentration of sugars to crystallize, he said.