But in fact, only vitamins are lost in the process of canned food processing, and manufacturers usually add vitamins in their production.
In terms of production technology and management level, canned fruit enterprises all carry out very strict control. Canned food not only peels and cores, but also completely eliminates pesticide residues on the peel. Sealing, high-temperature heat treatment and vacuum preservation can achieve the most thorough sterilization effect. Therefore, there is no need to add any preservatives to canned fruit, and it depends entirely on the sealing of the container and the long-term high-pressure sterilization of the food, thus retaining the flavor and nutrition of the food to the maximum extent.
General canning processing enterprises will adopt international advanced canning technology to realize vacuum packaging under the condition of high temperature sterilization. In this way, canned food is stored in a vacuum aseptic state without adding any additives.
The reason why canned food can be preserved for a long time without deterioration is entirely due to sealed containers and strict sterilization, which has nothing to do with preservatives. In fact, canning is not mysterious, and the principle of canning is also very simple: first, fully heat the raw materials to kill all microorganisms; At the same time, fully heat and sterilize the packaging tank; Then put the sterile food into a sterile container and seal it while it is hot; Finally, heat and sterilize. After cooling, the volume of air in the gap at the top of the container is reduced, which will produce negative pressure, so that the originally sealed bottle can not be opened and the bacteria outside can not enter. After these processes, food will naturally not rot, and there is no need to add any preservatives.
It is not a vacuum-packed can, nor can it be called a can.
Canned food was invented 200 years ago, when there were no preservatives.
Besides being safer, canned tomatoes are even more "fresh" than fresh tomatoes. Although we can easily buy "fresh tomatoes" from all over the world, they just look fresh, but the nutrients are constantly losing. Because any fruits and vegetables continue to "breathe" after picking, some nutrients will continue to decrease. The whole process of canned tomato from picking raw materials to processing is less than 6 hours. High temperature heat treatment will stop or slow down the chemical reaction of nutrient loss, and maintain the freshness and nutrition of food. Therefore, canned tomatoes are fresher than "fresh" tomatoes grown in long-distance transportation or greenhouses.
Moreover, the production of canned food has national standards. It's definitely not canned food with preservatives.
For reference.