Reasons Why Canned Food Can be Preserved Without Preservatives

Reasons why canned food can be preserved without preservatives
In the 1970s and 1980s, tomatoes and noodles could be eaten in winter. At that time, when tomatoes were on the market in large quantities, many people bought them home and made tomato sauce for use in winter. The method of making tomato sauce at home is very simple. It is to wash the tomatoes, blanch them, peel them, put them in a salt water bottle, then put in a rubber stopper, insert a needle, and steam on the steamer for about 30 minutes, then pull it out. The needles, cool, so that the tomato sauce can be stored until winter, and the flavor and color are excellent. The principle of making canned food is the same as making ketchup at home. The raw materials are processed, put into cans (iron cans, glass bottles or flexible packaging bags), vacuumed, sealed, and then heated and sterilized. After cooling, the finished cans are ready. After the food is put into the tank, after exhausting, sealing, and sterilizing, the container is completely sealed in an oxygen-free environment to achieve this aseptic state of the sealed food. There is no condition for microbes (bacteria) to grow and multiply outside the tank. The bacteria can not enter the tank, so the food will not spoil, and there is no need to add any preservatives. In addition, canned food has a history of more than 200 years, and there was no preservative at all at that time. Canned food is a safe, nutritious, convenient and convenient food. China's canned food exports about 3 million tons per year and is sold in more than 100 countries. Most aerospace and submarine foods are canned foods. In fact, canned foods are closely related to our lives. The sweet corn, tuna, mushrooms, tomato sauce, fruit in yogurt, and decorative fruits for birthday cakes in the catering industry are all canned foods. As raw materials, the eight-treasure porridge on the market is a typical canned food.