The hottest right and wrong fresh-keeping film

2022-10-20
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Right and wrong -- plastic wrap

plastic wrap should be used as little as possible in supermarkets, and meat food packaged with plastic wrap for sale can be seen everywhere. However, is such packaging safe

investigations have shown that some PVC plastic packaging products contain a plasticizer called DEHA for short to increase the adhesion of fresh-keeping film, but it will penetrate into food, especially high-fat food. Computer control of all experimental processes

the American Consumer Federation recently tested packaged cheese and found that 7 of the 19 products packaged in fresh film in fresh supermarkets contain a high amount of DEHA, with 51-270 units per million units, with an average of 153 units, exceeding the safety range

the allowable range stipulated by the European common market countries is that each million units can only contain 18 DEHA units at most. Because it has been proved harmful only in animal experiments (such as white mice), the U.S. government has not banned the use of DEHA in industry. Britain has stipulated to use other safer plasticizers as early as 10 years ago. However, some consumers in the United States have begun to reduce the use of plastic wrap for food packaging

today, when plastic cling film is still widely used, as a consumer of B-pillar guard board, you can also take self-protection measures: take meat and other food out of plastic packaging of cling film and put it in other containers as soon as you go home; You can also peel off the surface of the meat and discard it

if possible, wrap the meat in paper or self-contained paper. The food is packed in a ceramic bowl. If it is covered with plastic products, don't touch the food. In addition, when cooking or heating in a microwave oven, never let food touch the plastic film

use plastic wrap scientifically. Do not cover hot dishes with plastic wrap. When vegetables are hot, covering with plastic wrap will not protect vitamin C in vegetables, but will increase its loss. For example, the vitamin C of cabbage without film is 85%, while that of cabbage with film is only 71%; 97% of cauliflower was not covered with film, while only 58% of cauliflower was covered with film. Other vegetables have similar results. It can be seen that only when the vegetables are completely cooled, can they be covered with fresh-keeping film to protect vitamin C. Don't cover the freshly fried dishes immediately, otherwise it will backfire and backfire

the freshness depends on the "dish". When the reality covered with food preservative film does not help us to care about its importance, the test is extended to 24 hours. 2. The required load or stiffness tolerance is very close, and the result is different from that of 6 hours. Its protective effect on vitamin C cannot be generalized, but varies from "dish" to "dish". For example, the vitamin C content of 100g leek covered with plastic wrap increased by 1.33mg compared with that without plastic wrap, and the lettuce leaf increased by 1.92mg. These results are similar to the results of 6 hours. However, some vegetables are quite different. For example, after 100g concanavalin film is stored for 24 hours, vitamin C decreases by 1.5mg and radish decreases by 3.4mg. What's more, 100g cucumber actually reduced 3.8mg vitamin C. That is to say, after a bowl of cucumber covered with film is stored in the refrigerator for one day and one night, the loss of vitamin C is equivalent to eating five apples less

cling film also plays a role. Compare the vegetables with and without cling film placed in the refrigerator for 6 hours (that is, put the vegetables at noon for dinner). It is found that the vegetables with cling film do play a role in protecting vitamin C. For example, the vitamin C content of 100g tomatoes without film is 19mg, while that of covered tomatoes is 22mg; 100g white gourd contains 25mg and 30mg vitamin C respectively, and white radish 25mg and 27mg respectively. We know that the vitamin C content of 100g raw pears is about 3mg, so the vitamin C content protected by the fresh-keeping film is equivalent to eating an extra raw pear. Fresh keeping film has a greater effect on green pepper. Each 100g of green pepper with and without film contains 59mg and 66mg of vitamin C respectively, which is equivalent to eating more vitamin C from a big peach. Therefore, covering fresh-keeping film on vegetables in the refrigerator can improve their nutritional value

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