Introduction For Canned Food

We have a lot of food misunderstanding, such as canned, convenient and delicious, the key is the shelf life of up to 1 ~ 3 years. When it comes to foods with a long shelf life, people worry about whether they contain preservatives. The canned food we eat in our daily lives and on our travels is also being questioned. So, do canned foods really contain preservatives?

- How to prevent the Canning from corrosion?

The reason why Canning is not perishable is through the technical process to achieve.
The reason why food can rot, deterioration, mainly due to bacteria, mold and other "microorganisms" reproduction.
Canning, on the other hand, can be sealed and sterilized at high temperatures to achieve commercial sterility. When it cools down, the negative pressure in the container seals the can tighter, and there's no way for the outside bacteria to get in.
After these processes, the canned food is in an environment where there are virtually no microorganisms and it is almost impossible for it to decay, so most do not require additional preservatives. Only a few cans require preservatives to deal with certain microorganisms to ensure food safety.

- Is it against the rules to put preservatives in cans?
The national standard for the use of food additives in food safety (GB2760-2014) also clearly stipulates that no preservatives shall be added to canned food.
According to GB27602014 food safety national standard for the use of food additives, canned fruits are not allowed to add any preservatives, if found in canned fruits added preservatives, it is illegal. The high sugar, oxygen-free environment in canned fruit is not suitable for microbial growth, so as long as the sterilization is thorough, no need to add preservatives.
However, canned meat may contain some anaerobic microorganisms due to the more complex types of microorganisms in the meat. Some additives such as streptococcus lactis, Sodium Nitrite, potassium nitrite, etc. can be used under the national standards. As far as the production technology in China is concerned, most of the factories can ensure the long-term storage of canned food under suitable conditions only by sterilization process without additional preservatives, and no preservatives are allowed in the canned meat.

- Does canned food have any nutrition?

Canned food is also often thought of as a non-nutritious food, but this is not the case.
Can is used to sterilize autoclave sterilization, its sterilization temperature is generally about 120 °C, and vegetables, fruits sterilization temperature is lower, generally 80-90 °C. At this temperature, most of the nutrients in the can are well preserved, and only a few heat resistant vitamins, such as vitamin C, vitamin B6, and vitamin B9, are destroyed.
Even if the home cooking, sometimes temperature can reach 200 °C, canned sterilization temperature is not as high as stir-fry vegetables, its nutrients should be better than the usual way of cooking food preservation.

- How to choose a Can?
When buying canned food, pay attention to the shelf life and the appearance of the can. Observe whether there is rust in the can, whether the lid or the bottom of the can is swollen or sunken, and whether the center of the glass can lid is concave. If there is such a phenomenon, it means that the can is not well sealed and the inside of the can is infested with micro-organisms, not to be purchased. When buying canned food online, it is often possible for the canned food to deform due to the transportation or storage environment. If the canned food is deforming but the cans are not bulging or bursting, the product can still be consumed normally, should not continue to consume the canned food.
For canned deli meat, the latest release does not mean the best condition, production date from the actual opening date of 6 ~ 9 months of the product has some advantages. At this stage, the food in the can can can after a period of time interaction, taste gradually optimized, taste to a better state of fusion, the most suitable for consumption. Too Long or too short canning time may have different effects on the flavor and taste of canned food.