Freezing Food There are times -or seasons- when it is not possible to buy daily or cook. Many people take advantage of the weekends to prepare and freeze the food for the following days. Dietitians-nutritionists confirm the benefits of this practice, as long as it is not done in any way, but rather that guidelines are followed that guarantee food safety and, incidentally, the properties and taste of food.
It should be borne in mind that, as the food technologist and dietitian-nutritionist Beatriz Robles points out, “nutrients begin to be reduced from the moment vegetables are collected or animals are slaughtered.” From that moment, “any treatment or process produces changes, both positive and negative.”
Freezing, if it is fast and at very low temperatures, as with deep-freezing, preserves the nutritional properties of food very well. At home, according to Robles, “although the loss is slightly greater than when the process is carried out in the industry, it is not significant, mainly because eating a varied diet allows us to be unconcerned with the small changes that may occur.
Picture Your Freezing Food Yes, But Not In Any Way On Top. Read This And Make It So
Conservation at low temperatures “allows stopping, or rather slowing down, the main food alteration reactions”, explains Mar Larrosa Pérez, researcher and professor in the area of Nutrition and Food at the European University. “In this way, its useful life is extended.” Sara Martínez López, researcher and professor in the same department, adds that freezing “induces organoleptic changes in food, negatively affecting taste, color, odor or texture. However, this impact is minimal compared to other conservation methods ”.
To guarantee maximum safety, Larrosa points out that the freeze “should only be applied to products that are in good condition. In addition, it would be advisable to do it as soon as possible, to avoid accelerating the alteration process .On the other hand, foods that are marketed already frozen keep at these temperatures until consumption, without interrupting the cold chain.
Most foods withstand freezing well, but there are several exceptions. Here are some examples of products that do not hold up well after freezing and thawing: Foods high in fat can become rancid by freezing. “It is not a food safety problem, but it produces changes in taste and odor,” says Robles. Eggs in shell cannot be frozen because they would explode with increasing volume of their inner contents. Foods with a high water content, such as fruits and some vegetables (potatoes or carrots) lose properties related to texture and flavor when frozen. Specifically, cooked potatoes acquire a gritty texture when thawed.
Rice and pasta
Dishes made with pasta and rice also tend to withstand freezing and thawing poorly and lose organoleptic properties.
Freeze raw or cooked food? Freezing is valid for both raw and cooked food. Martínez comments that, in the first case, “you have to be especially careful with the process, while in the case of cooked food, the most important thing is not to freeze the food hot. In this way we avoid a sudden change in temperature, which would reduce the performance of the freezer and affect the food to a greater extent ”.
Robles offers a simple trick so that raw vegetables do not lose their properties with freezing: “It is advisable to blanch before freezing them. First they are put in hot water -over 70º C- for 2-3 minutes, then they are passed through cold water and they are ready to freeze ”. What is achieved in this way is “that some enzymes that cause changes, especially color, are destroyed.” This is applicable to green beans, spinach, Swiss chard …
The experts highlight the following basic guidelines so that the freezing and thawing process is as safe as possible and fully respects the properties of food: The microorganisms present in food “slow down due to the cold, but do not die,” says Larrosa. “Thawing activates the changes they cause again.” In practical terms, we must forget to freeze that stew that has been in the fridge for four days and, finally, we decided that we do not want to eat it at the moment. If we do it, when we defrost it, it will have the same microbiological quality as when we put it in the freezer, that is, quite precarious.
The ideal is to freeze directly, once it has cooled, what we have just cooked; or what we have left over from the food that same day. The containers can be plastic or glass, as long as they are suitable for freezing. It is usually indicated by the packaging itself. The most practical thing is that the same container serves both freezing and microwave.
Freezing bags and aluminum foil can also be used, taking the precaution of wrapping food tightly so that what is known as a cold burn does not occur, which makes the parts that are not covered become dry and lose organoleptic properties.
A good idea is to freeze them in containers equivalent to one serving or the size corresponding to what the family unit is going to eat, since after defrosting it cannot be frozen again.
Defrost in the fridge
The most advisable thing is to defrost the food in the refrigerator, where they must remain for a time that will vary depending on the type of product and the quantity. For example, thick meats can take up to 24 hours to defrost in the fridge.
A very popular alternative is to defrost in the microwave, on low power and stirring occasionally. Doing it at high power usually alters the texture of the food. What you should never do is defrost at room temperature, since it compromises food safety.