How Is Frozen Food Safe Without Preservatives?

The freezer is one of those modern appliances most of us can't imagine living without. Holiday food leftovers? Put them in the freezer. Meat on discount? Buy in bulk and freeze. Anticipating a busy week? Stock up on freezer meals. This food preservation method has ancient origins and, per the FDA, it can actually keep food safe indefinitely. But have you ever wondered why frozen food doesn't spoil, even with no preservatives added? When food is frozen to a temperature of 0 degrees Fahrenheit or below, the bacteria that can cause foodborne illness enter a dormant stage. For as long as the food remains frozen, the bacteria will not grow.

It's important to know that freezing the food doesn't kill the bacteria; it only stops their activity. Dormant bacteria, also called spores, are very resilient and can survive many years in their sleeping state. They're still able to monitor their environment and when they sense favorable conditions, such as optimum temperature and nutrients, they wake up and become active once again. In practical terms, this means your food is safe from bacterial activity while it is frozen ... but as soon as you thaw it, the bacteria begin to grow and multiply.

Once the previously frozen food is thawed and the bacteria is woken up, it's crucial to keep the food outside the unsafe temperature range where it could spoil. The FDA calls the range between 40 and 140 degrees Fahrenheit the "danger zone," because it's within this window that bacteria grow the fastest — for example, they can double in 20 minutes. The only way to keep your food outside the danger zone is to refrigerate or freeze it (depending on whether it's short-term or long-term storage), or to cook it for immediate consumption.

Although frozen food is safe from bacterial activity even without preservatives, freezing can still impact the food's quality. Don't wait until the last moment before the food spoils to freeze it — do so while it's still at maximum level of quality. Frozen foods keep their nutrients, but they may have a different texture and flavor when they thaw, especially if they were frozen for a very long time. Another thing you might notice on your frozen food is freezer burn. It certainly doesn't look pretty, but it's actually not unsafe. It does impact the texture, though, so you'll want to take a peek at our simple method to prevent freezer-burned meat, for instance, if you're looking to avoid this.