First, the nutrients in frozen food will be gradually lost.
As we all know, fresh food contains high nutrients, while quick-frozen food will lead to the loss of nutrients. In real life, quick-frozen jiaozi is a very common quick-frozen food. Because the temperature is too low, vegetables and meat stuffing will lose some nutrients during processing, and vitamins in food will slowly decompose during transportation and storage. And with the extension of storage time, the loss of these nutrients will become more and more serious. Therefore, compared with homemade fresh food, the nutritional value of quick-frozen food has actually been greatly reduced.
Second, the total number of colonies in quick-frozen food exceeded the standard.
Frozen food can be said to be unsanitary. Many quick-frozen foods contain a lot of bacteria, especially bulk quick-frozen foods. These bacteria may bring in various pathogenic microorganisms before freezing because of the bacteria in raw materials, the continuous reproduction of bacteria during processing, the bacteria-carrying operation of production personnel and the uncleanness of machinery and equipment. Although low temperature can inhibit the reproduction of microorganisms, it can not effectively kill them. Once the temperature is restored to an appropriate level, microorganisms will become active again, thus increasing the hidden danger to health.
Third, food is oxidized and deteriorated.
During the storage of frozen food, with the oxidation of fat, the taste and appearance will change or even deteriorate, which is a great threat to health.