Freezing food is one of the ways we can safely keep our food for later consumption. With most people having a freezer in their kitchen, frozen foods are now an everyday convenience. 

Nonetheless, we may still be wondering about food safety, and doubting whether the freshness and quality of our food are properly preserved. Food safety experts assure us that freezing food is actually one of the safest ways to preserve our food, and some would even say it is much safer than home canning. Although there may be issues with quality, safety is not a concern. Furthermore, the freezing process keeps most of the foods’ nutrients intact - there is little change in nutrient value, especially in meat in poultry products.

Safety Concerns 

According to the US Food Safety and Inspection Service, food will always be safe when stored constantly at 0 °F (-17°C). This is because freezing slows down the movement of molecules, making microbes enter a dormant state. It also preserves food for a long period of time due to the prevention of the growth of microorganisms that cause spoilage in food and foodborne illnesses.

Freezing can actually be instrumental in killing parasites in your food. According to the Centre for Food Safety in Hong Kong, when exposed to temperatures of -35℃ for about 20 hours or -20℃ or below for seven days, parasites in fish can be killed by freezing. Therefore, in order to make safe sushi and sashimi, the freezing temperature and time combination will have to vary depending on the types of parasites being targeted.

The Risk is in Thawing

Usually, we pull frozen food out of the freezer and leave it on the kitchen counter for a few hours or overnight to thaw. As such, the surface of the meat (or the frozen food) reaches room temperature before the core is thawed. If there are bacteria on the surface, then they will be growing at a normal rate. 

Therefore, it is not advisable to refreeze food that has been thawed outside a fridge. Aside from safety issues, both the taste and texture of the food will be compromised.

Are there foods that should not be frozen?

The United States Department of Agriculture says we can freeze just about any type of food. However, keep in mind that some foods like salad greens, whole eggs, and egg yolks do not freeze well. Also included on this list are mayonnaise and cream sauce, so you might need to think twice about freezing your tuna or chicken salad.

How to Safely Store Frozen Food

It is important to keep frozen foods in a well-wrapped packaging or tightly-sealed container. Proper packaging prevents freezer burn. These are the grayish-brown leathery spots that are the result of air by air coming in contact with the surface of the food. It dries up a portion of the food but does not make food unsafe. So in case, you notice that packaging has been torn or opened while your food is in the freezer, it is best to rewrap it or put a covering over the exposed part.

Ultimately, frozen food is safe as long as the cold chain (the temperature-controlled supply process from preparation to storage) is not broken. For some foods, the chain may take longer as they go through packaging, storage, distribution, retail holding, or display. It is therefore essential to buy from reliable and hygienic suppliers, especially for your meat, poultry, and seafood products.