We all know the benefits of freezing meat. It allows us to keep more variety and larger quantitates on hand so that we are not going to the supermarket every day to get what we need. Once we are ready to use the frozen meat it needs to be de-frosted. But once meat is defrosted can it be refrozen if we no longer need/want to use it?
There are actually multiple parts to this question and we will start by unpacking the section which is how you should defrost frozen meat.
Before we talk about defrosting meat, let’s establish a fundamental Food Safety term called the Danger Zone. The Danger Zone refers to the range of temperature in which bacteria can grow. Below this, bacteria reproduces incredibly slowly as it is too cold to metabolize and reproduce effectively (4C). Anything below 0C (32F) the bacteria goes dormant and does nothing at all. Above the Danger Zone, it is too hot and bacteria dies (60C). This means that our Danger Zone is from 4C – 60C (40F – 140F). Basically, if you are uncomfortable and have difficulty completely tasks, so are the bacteria that make food spoil. If you are comfortable and can actively complete tasks, so can the bacteria. They like the same conditions we do.
Now that we have established our Danger Zone, let’s discuss how to defrost meat. If the Danger Zone is from 4C – 60C, and room temperature is around 20C – 25C that means that room temperature is almost right in the middle of the Danger Zone. Fridge temperature is from 0C – 4C (32F – 40F) and thus is below the Danger Zone. Therefore, the best and safest way to defrost meat is in the fridge as it will never enter into the danger zone. You can defrost meat at room temperature but as the meat defrosts it enters the Danger Zone and starts to create the ideal conditions for bacteria to grow. Thus if you are doing it this way, you should submerge the product in cold water, only leave it out for 2 hours at most, and cook the meat as soon as possible. However, leaving it outside of the fridge is never as safe as leaving it inside the fridge to defrost.
With the knowledge of the best way to defrost meat, let’s address the act of refreezing. If a product is frozen that means that it is colder than 0C which means that the small amount of bacteria on the meat is not doing anything. If you defrost it in the fridge, we know that a fridge does not operate above 4C so therefore the meat does not go above 4C. If it does not go above 4C, then it does not enter the Danger Zone. If you then freeze the item again, it starts to go back down below 0C. The item never enters the Danger Zone and thus the bacteria never has a chance to reproduce at a rapid rate. Therefore, there is no safety issue around refreezing meat.
Now for a bit of a disclaimer. These conclusions are made around the assumption that you started with fresh meat, froze it immediately after buying/receiving it, and left it in your fridge for only a day or 2 before refreezing. The first point is that if your meat is spoiled, there is no act that will bring it back. Spoiled meat cannot be saved and should be disposed. If you take it out of the freezer, thaw it in the fridge, leave it there for an extended period of time, then refreeze it, it will still be spoiled when you go to thaw it again. If you thaw the meat in the Danger Zone by any means (even running under cold water) do not refreeze the meat. By leaving it in the danger zone you have drastically reduced the shelf life of the meat. It should be cooked as soon as possible in order to kill the bacteria before being refrozen.
Finally, although there is no safety issue around refreezing meat (only if it is done properly) there is a quality issue. To read about this, visit our page on What Happens to Meet When it Freezes. To sum it up, when meat freezes, the ice crystals puncture the cell walls and start it break down the meat. Generally, you will not notice the difference on the first thaw, but if you refreeze the meat, the structure will break down even more and your meat will have a softer/soggy texture.