The Truth About Freezing and Thawing

By Diane Wright Hirsch, MPH, RD

UConn Extension Educator – Food Safety

inside freezer
As I am writing this, it is snowing lightly outside my office window. I am thinking about the potential weather fluctuations. Lots of folks have filled their freezers and refrigerators in preparation for the storm. But what happens when the power goes out?

This time of year (as opposed to hurricane season), we are lucky that the temperatures are such that we can use the out of doors as one huge refrigerator/freezer. Over the next 8 days it looks like temperatures in my neck of the woods won’t reach much over thirty—and then only for a day or two and then it is back to the deep freeze.

One question I frequently get after a widespread power outage—or, at any time, really—is, “Is   it ok to refreeze food that has defrosted.” Many have been scared into thinking that once a food thaws, it is no longer safe to refreeze or, maybe, even to eat. So, let’s go through two possible defrosting/refreezing scenarios and use a bit of food safety science to explain what happens and what is your best course of action. Before we go any further, though keep in mind that having a couple of food thermometers on hand will help you to make food safety decisions. It would be best if you have one in the freezer (so you can tell if your freezer is still capable of freezing!). Also, have on hand a food thermometer—the same kind that you can use for checking to see if food has cooked to the proper temperature. This thermometer will tell you the actual temperature of the food you are checking on: this is not so important if the food is frozen, but once it defrosts, it can help you with the should I keep it or toss it question.

Your electricity is out—no freezer or refrigerator.

One tool, actually two, that will help you with this is the thermometer.

Once the food defrosts, try to keep it cold by keeping it in the freezer/refrigerator (or outside if it is cold enough). As long as the food stays at 40 degrees F or below, you can refreeze it within a day or two, or maybe even three (fish, ground meat and poultry and similar food with high perishability should be refrozen within 24-48 hours).

Alternatively, cook and/or eat it while it still registers 40 degrees F or below on the thermometer. If both your freezer and refrigerator are out of service, then keep in mind that you should only cook what you can eat – there will be no way to cool down the leftovers for refrigeration.