Southern Living Magazine: As it sits on your countertop [at a warm temperature], it creates a perfect environment for bacteria to start growing again, so it’s important to get it back in the fridge before too much bacterial growth takes place,” says food scientist Caitlin Clark, M.S., a Ph.D candidate in the Department of Food Science and Human Nutrition at Colorado State University. “A good rule of thumb is that it shouldn’t sit out for more than two hours before being refrigerated.”

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