Seven, 80s, in the winter can eat tomato noodles, how much enjoyment and pride! At that time, many people bought tomatoes when they were listed in large quantities, and made tomato paste for winter use. The method of making tomato sauce at home is very simple, that is, wash the tomato, heat the skin and put it in the saltwater bottle. Then, plug the rubber plug, insert the needle, steam it on the steamer for about 30 minutes, remove the needle and cool, so that the tomato sauce can be stored in winter, flavor and color and lustre.

The production of canned food is the same as the principle of making tomato sauce in the family. The raw material is treated well, loaded into the tank (iron tank, glass bottle or soft packing bag), vacuum sealing, and then heated and germicidal, after cooling, the finished product is finished. After the food is loaded into the tank, after the process of exhaust, sealing and sterilization, the container is completely sealed and is in the anaerobic environment to reach the sealed food of this aseptic state. The microorganisms (bacteria) have no conditions for growth and reproduction. The bacteria outside the tank can not enter the tank, so that the food will not be corrupted, and there is no need to add any prevention at all. Rotten. Besides, canned food has a history of more than 200 years, and there was no preservative at that time.

Canned food is safe, nutritious, convenient and convenient. In Europe and America, Japan is very popular. China's canned food exports about 3 million tons a year, and is sold in more than 100 countries. Most of the food in space and submarine is canned. In fact, canned food has been closely related to our life. The sweet corn, tuna, mushroom, tomato sauce, fruit grains in yogurt, and the ornamental fruit of the birthday cake are all made of canned food, and the eight treasure porridge is a typical canned food.