Millions of Germans lack the time and desire to cook due to professional or private stress: Instead of a freshly prepared meal, a finished frozen meal ends up on the plate. In recent years, the per capita consumption of frozen foods in Germany has risen sharply. So he tripled between 1975 and 2008 from about 12 kilograms to 39 kilograms. But are frozen foods healthy at all? And what do you have to consider when storing, thawing and preparing the products? We answer the most important questions.
The term frozen food covers foods that have been preserved by deep-freezing. Important when freezing is that the process is as fast as possible. Because then only small ice crystals form in the cells and cell interstices, which cause no damage. During slow freezing, on the other hand, larger ice crystals are formed and cells can be destroyed.
If cells are damaged during freezing, the taste and texture of the food change. However, this is not the case with fast-frozen foods that are thawed slowly and gently. In addition, vitamins and other nutrients are particularly well preserved.
The nutrients contained in the food can be preserved, above all, during so-called shock freezing, which is currently the fastest method of freezing. Here, the food is frozen at below minus 30 degrees. This quickly forms a thin, frozen layer around the food that prevents liquid or nutrients from escaping.
Quality of frozen food
The freezing of food is particularly gentle compared to other preservation methods. The faster the food is frozen, the better its quality is maintained.
In order to preserve the quality of the frozen products, it is important that the cold chain is not interrupted. Therefore, frozen food should be placed in the car only at the end of the shopping. For a long journey home or high outside temperatures, the frozen products should be transported in an insulating bag. If such a bag is not at hand, several frozen foods should be stored close together to keep the cold better.
In addition, you should also consider the following aspects when purchasing frozen foods:
- Do not buy products whose packaging is damaged.
- Check the temperature of the freezer - often it contains a thermometer: The temperature should be at least minus 18 degrees.
- Do not buy products that are stored above the stack mark. Sufficient cooling is then no longer guaranteed.
- Check the cleanliness of the freezer: If ice has formed inside the chest, the cooling can be disturbed.
Healthy frozen vegetables
Frozen vegetables are considered to be a healthy alternative to fresh vegetables, because fast freezing keeps many vitamins and minerals intact. Therefore, the nutritional content of frozen vegetables is significantly higher than that of vegetables stored in jars or cans. Often, frozen vegetables have even more nutrients than fresh fruits or vegetables that have been stored for a few days at room temperature. Because by light and heat, the nutrient content decreases significantly over time.
In addition to the nutrients, the taste and consistency of the vegetables are almost completely preserved with rapid freezing of the products. In addition, preservatives are not needed to preserve the frozen vegetables.
To ensure that frozen fruits and vegetables are still valuable foods even after thawing, strict quality criteria apply during production. These include a perfect condition of the raw material, the harvest at the right time of maturity and the rapid processing of the food. In addition, before freezing, vegetables are generally still blanched to extend shelf life and reduce the number of germs.
Stay away from ready-made frozen foods
Whilst frozen fruits and vegetables should be seen as healthy, ready-to-serve frozen foods should be viewed more critically, as prepared meals are usually created in the laboratory using colorants, flavorings and preservatives, as well as flavor enhancers and binders.
However, there are great differences between individual products in finished frozen meals. For example, in a quality test carried out by the Stiftung Warentest, it was found that some ready-meals were almost without additives. That is why it is particularly important in finished frozen meals to pay close attention to the quality of the product. In general, however, that individual ingredients for a self-cooked menu may well come from the freezer, but should be better avoided on frozen foods.
Tips for Thawing Frozen Food:
To best maintain the quality of frozen products, consider the following tips when thawing:
- Thaw frozen foods always in the fridge. At higher temperatures, the goods may spoil.
- When defrosting, make sure that the food is dry and does not come into contact with the defrosting liquid. This is especially important in poultry because salmonella can accumulate in the thawing water.
- If possible, use frozen products within 24 hours after thawing.
- Frozen vegetables should not be thawed, but frozen or prepared otherwise it may cause a loss of nutrients. To keep this as low as possible, the frozen vegetables should be cooked only briefly, but hot.
- In addition to frozen vegetables, many other frozen products such as pizzas, potato products, snacks or bread rolls can be prepared frozen.
- However, products that are eaten cold - such as smoked fish, fruit or pies - have to be completely thawed.
Frozen foods - re-freezing possible?
The indication that frozen products should not be frozen again after thawing must not be missing on any frozen product. However, according to the German Deep-Freezing Institute, the re-freezing of food that has already thawed once is quite possible under certain conditions - especially with cooked or highly heated foods.
It is important that the thawed products are frozen again as quickly as possible: Because in the thawed state, microorganisms spread and the food can spoil during prolonged storage in the refrigerator. Therefore, before eating, the frozen products should be thoroughly heated to kill possible germs.
By re-freezing, however, usually suffers the quality of the product, since it does not cool down as fast in its own freezer as in shock freezing. In addition, important nutrients are lost. Therefore, the required portion should always be estimated as accurately as possible and a re-freezing of the products should be avoided.
Quality of self-frozen foods
The storage temperature of industrially manufactured frozen products must be minus 18 degrees or lower. Ice cream is therefore not part of the frozen food, as it can be stored at higher temperatures. During transhipment operations - for example during transport - deviations of up to three degrees are permitted.
Even frozen foods are not referred to as frozen foods, but as frozen foods. They have a lower durability, since they are stored at higher temperatures. In addition, the quality of self-frozen products is lower as they freeze more slowly than frozen products from the trade.
Before entering the market, frozen products must be labeled as such, for example by the words 'frozen' or 'frozen'. In addition, the packaging must have the best before date and the recommended storage temperature.