It is most suitable for eating after 20 days. The environment in the tank is conducive to the reproduction of overstocked bacteria (including some nitrate-reducing bacteria) and can promote the reduction of nitrate to nitrite. However, with the extension of curing time, lactic acid bacteria also proliferated in large quantities, which inhibited nitrate-reducing bacteria to some extent, affected their growth and reproduction, and reduced the nitrite content in kimchi again.

After 20 days, the content of nitrite will drop to a very low level and become nitrate.

Long-term excessive intake of nitrite will greatly increase the risk of cancer. Pickles cooked at home every day have the highest carcinogen content in 1-3 days, and they should be eaten after 20 days. The highest content of nitrite is 1 at 0-3 days after pickling, and its content is on the rise during this period. So 1-3 days don't eat "kimchi".

Generally speaking, from the third day, the oxygen in the pickle jar is exhausted due to the continuous reproduction of microorganisms, and the nitrate in vegetables is gradually reduced due to oxidation, so the nitrite content in pickle will gradually decrease and tend to a relatively stable value. But it will take nearly 15 days. Therefore, in the middle of pickling, the lid of kimchi must not be opened, because the entry of oxygen is not conducive to the reduction of nitrite content.

After pickled kimchi for 20 days, the nitrite content will indeed drop to a very low level and become nitrate. It is generally believed that it is safer to marinate for 30 days. But nitrate is not good for human body, but it is not as harmful as nitrite. You can change your taste once in a while, instead of eating all the time. 1-3 days pickling is the time period with the highest carcinogen content, so it should be eaten after 20 days. So kimchi stored for a long time (more than 30) is healthier!