How to correctly understand the canned foods

Canned food as a store class of food, in domestic market Shang is snubbed, but in abroad market Shang is very by consumers of favored, this is because many of consumers for canned food of awareness has a errors, summary up has four points: 1, and think canned food not security, and has preservatives, and has pesticide residues; 2, and think canned is didn't nutrition of food; 3, and think canned save time long, must is not fresh of food; 4, and just put canned as visits patients or out outing of food.
First, canned foods do not contain any preservatives
Canning technique is invented by French scientist Abel. As early as 1810, he puts food through the exhaust, sealing or sterilization to the long-term preservation and not corrupt. By 1862, scientist Louis Pasteur further clarified the principles of canning,namely food sealed, external microbial contamination no longer, after high temperature disinfecting, keep food in sterile, which is the scientific principles of canning methods. After more than 100 years of development, canning techniques perfected, canned food is believed to be human * easy, * one of safe and healthy food. Canned food preservation depends on vacuum, sealing and sterilization. After canned food into, after exhausting, in a vacuum, resulting in oxygen-free environments, the container completely sealed, full sterilization under high pressure. Therefore, about canned foods do not need to add any preservatives, can achieve the objective of long-term preservation.
In our daily lives, access to many foods, some foods to achieve a longer preservation, have to use preservatives. For example, cakes and candied fruit, instant noodles and soy sauce. Canned foods through vacuum sealing and sterilization, ** do not contain any preservatives, it is canned food is different from the characteristics of the foods mentioned above.
Second, health food, canned food is * safety
Canned food safety, health, in Europe and other developed economies ** and by the public. Canned food security and health assurance is mainly due to:
1, Tin container has good performance of preserving food. Cans are usually divided into cans (aluminum foil material) and hard can (tinplate cans and bottles and cans)and make containers the material is nontoxic, tasteless, has good stability and sealing properties. Welding technique of canning is a *** in today's world of high frequency resistance welding, welding can reach speeds of 600 cans per minute. Bottom cover using a high sealing performance of rubber filled, so canned food can be completely sealed.
2, canning and processing secure, food vacuum pump air formation after mount container, sealed external bacteria could no longer enter sterilization residual bacteriakills. Food in vacuum and under sterile conditions, you can ** limited preservation ofcolor, aroma, taste, and preserved for a long time. Abroad have had such coverage,canning place decades later, still intact, in line with the standard.
3, the canning