Pickles should be soaked for more than two weeks before eating. Generally speaking, the most nitrite in pickles is between two or three days and ten days after pickling: when the temperature is high and the salt concentration is low, the "nitrite peak" appears earlier; On the contrary, when the temperature is low and the salt content is high, the "nitrite peak" appears later. Pickling pickles and sauerkraut generally takes more than one month in the north and more than 20 days in the south. Generally speaking, right
After 20 days, the content of nitrite decreased obviously, and it was very safe after one month. The real threat to food safety is the kind of vegetables that are only pickled for two or three days to ten days. Vegetables preserved for more than one month can be safely eaten.
Adding some onions, ginger, garlic, pepper juice and lemon juice when pickling vegetables can reduce the content of nitrite. For example, organic sulfide in garlic juice and vitamin C in lemon juice can prevent nitrite from synthesizing nitrosamine carcinogens.
How is nitrite produced in the process of kimchi production?
At the initial stage of fermentation, microorganisms in kimchi grow rapidly, reducing nitrate in vegetables to nitrite. At the same time, phenols and vitamin C in vegetables can also oxidize nitrite, but generally speaking, the nitrite produced is greater than the reduced nitrite, so the nitrite content will gradually increase with the extension of fermentation time. With the continuous metabolic activities of microorganisms, oxygen is consumed. The environment in the pickle jar is not conducive to the growth of other microorganisms except lactic acid bacteria. At the same time, the nitrite content in vegetables is reduced due to oxidation, so the nitrite content will gradually decrease and tend to a relatively stable value.