Use notes of preservative film: do not use fresh-keeping film for these foods

At present, the food that is sold with plastic wrap is seen everywhere in the supermarket and is accepted by more and more families. The fresh-keeping film is gently covered to preserve the delicacy of the food and bring great convenience to the food. However, more and more studies have found that this handy convenience is not in fact safe. And some things can not use fresh-keeping film, not only can not keep fresh, but also cause harm to the body, let us look at it together.

Health hazard of fresh-keeping film

In order to increase its viscosity, transparency and elasticity, a certain amount of plasticizer has been added to PVC preservative film, and plasticizer contains a chemical compound, which has great damage to the endocrine system of human body, and it will disturb the hormone metabolism of human body. After a long time the fat in the food package, it is easy to wrap the harmful substances dissolved and, when heated, will accelerate the plasticizer in compound drug release to the food, after eating can cause breast cancer, birth defects, reduce the number of male sperm, or even mental disorders. At present, plasticizers have been restricted to use in Europe and are banned in Korea.

Not everything can be used as a preservative film

Apple, pear, rape, leek etc. water suitable for large Vegetable & Fruit film.  These fruits and vegetables use fresh-keeping film not only to keep fresh for a long time, but also to increase some of the nutrients. In the study, the scientists found that 100 grams of Jiuhuang wrapped in plastic wrap, 24 hours after the content of vitamin C than not wrapped 1.33 mg, 1.92 mg of rape lettuce leaves much.

But the experimental results of radish, cucumbers and beans were completely opposite. 100 grams of radish wrapped with fresh-keeping film stored for a day, its vitamin C content decreased by 3.4 mg, and the beans decreased by 3.8 milligrams. When cucumber was stored for a day and a night, its vitamin C loss was equivalent to 5 apples.

Precautions for the use of preservative film:

(1) just cooked hot dishes do not cover wrap, wrap is stamped when hot dishes, not only can not keep the vitamin C in vegetables, but will increase the loss. So, when the vegetables are completely cooled, the preservative film can be covered so that vitamin C can be protected.

(2) compare the vegetables covered with fresh-keeping film and the cool vegetables after putting 6h in the fridge, and find that the vegetables with the fresh-keeping film played a protective role in vitamin C. For example, 100g does not cover fresh-keeping tomatoes, its vitamin C content is 19mg, and the 22mg is covered with film; 100mg winter melon contains vitamin C, 25mg and 30mg respectively, while white radish is 25mg and 27mg respectively.  Therefore, after the cooking, the vegetables are covered with a plastic film to maintain its nutritional value, but the preservative film should be covered after the dish is cool.

(3) but if cooked vegetables placed in the refrigerator for more than a day, due to the preservation of food. When the food preservative membrane was extended to 24h, the result was different from that of 6h, and its protective effect on vitamin C could not be generalized. For example, 100mg stamped plastic wrap Jiuhuang, the content of vitamin C than with more 1.33mg, lettuce leaves 1.92mg, these results were similar with 6h. But some vegetables are very different, such as 100g bean cover membrane storage 24h, vitamin C instead of 1.5mg, radish reduce 3.4mg, cucumber reduced 3.8mg. So the preservative film is not a universal membrane, and it should be used according to the characteristics of the wrapped food.

(4) try to avoid the contact between the food and the film when using the fresh-keeping film in the microwave oven, especially the oily food. The preservative film covering the utensils should be tied up in several small holes to avoid blasting. When using, we should also pay attention to the temperature that can be withdrawn when the fresh-keeping film is heated, strictly according to the temperature marked above the brand, or choose a heat-resistant and better preservative film. Even though polyethylene (PE) fresh-keeping film is labeled with "microwave heating or high temperature use", it should be used with caution. So far, there is no authoritative test data showing that polyethylene film is safe under these conditions.

(5) for Steamed Buns, snack food like this, wrap is obviously very convenient, compared, fresh-keeping bag is relatively thick, the permeability is not very good, relatively suitable for some, but when used as far as possible not to seal the top die too. Cooked food, hot food and oil containing food, especially meat, is best not to be packaged with fresh-keeping film, and can be safely selected. The main function of fresh box is sealing, which can effectively isolate and store cooked foods and increase the utilization ratio of fridge space. In a word, only scientific and rational use of preservative film and other preservative products can be "preservation" and "insurance".