Sour radish, sour cowpea, sour cucumber...... Just listening to this series of reported dish names, is it already soft at the root of the tooth and tongue with relish?
Kimchi can be found everywhere in the mainland. Hunan's sour radish duck soup, Sichuan and Chongqing's sour bean meat foam, of course, there is the most spectacular, the northeast sauerkraut - in late autumn, a car of cabbage is transported to the downstairs of the community, and the autumn wind blows them to the dry skin, and then please go out of the sauerkraut tank and pressure cylinder stone at home, wait for a period of time, it becomes the sauerkraut white meat, sauerkraut vermicelli, and sauerkraut hot pot on the winter table......
However, there are different opinions about whether kimchi is good or bad for the body – some people say kimchi contains nitrites, which may cause cancer, while others say that kimchi contains lactic acid bacteria, which are probiotics, so kimchi is a health food. Which statement is correct? Today we will make it clear~
1
How is kimchi made?
Although there may be some differences in the preparation of kimchi in different places, in general, the vegetables are placed in a large jar, salt water is poured to let the water submerge the vegetables, and then the jar is sealed, and lactic acid bacteria are used to ferment and decompose the sugars in the food and release the acid.
An excellent can of kimchi needs to meet three words - "fresh", "sour" and "crispy".
Looking at the taste that humans are obsessed with, umami is perhaps the number one. The umami flavor in food often comes from some umami amino acids, such as glutamic acid, aspartic acid, lysine, tyrosine, etc. Whether it is the freshness of fish and sheep or the umami of mushrooms, they are inseparable from the flavor of amino acids. The monosodium glutamate, chicken essence and various umami-based seasonings used in our stir-fry are inseparable from the blessing of the above-mentioned flavor amino acids, for example, the main ingredient of monosodium glutamate is monosodium glutamate.
The fermentation process of kimchi, which is dominated by lactic acid bacteria, produces a large amount of umami amino acids. The study found that whether it is Sichuan kimchi, Jiangxi salt cabbage and Northeast sauerkraut, fermented vegetables are rich in amino acids such as glutamic acid, phenylalanine, alanine, aspartic acid and so on. Although the types and contents of amino acids in different types of fermented vegetables vary with the fermentation time, in short, the presence of these umami substances is the basis for the deliciousness of kimchi.
Lactic acid bacteria fermentation also produces organic acids. This sour taste is not as "stimulating" as the sour taste of vinegar, but is more mild and has a special sour aroma, which is the result of the organic acids changing during fermentation, producing alcohols and esters.
"Crispy" is not a taste, but a texture. People's love for "crispy" can be said to be instinctive: on the one hand, it comes from the desire for freshness – crisp fruits and vegetables usually represent plenty of moisture, freshness and fullness, and on the other hand, from the desire for a crispy texture after cooking. Crispy foods are often baked or fried, undergoing a Maillard reaction that brings out the aroma, tantalizing color and taste.
Compared with other pickled dishes, kimchi has won more people's love because of its unique crispiness. The "crispness" of kimchi is not only affected by the freshness of the pickled vegetables, but also by the length of pickling time, the pickling temperature, and the pH value in the kimchi jar. Therefore, kimchi seems simple, but the success rate of novices is not high. It is in the above details that the experts accumulate experience to marinate the crispy and sour delicious kimchi.
2
Is kimchi carcinogenic, high in salt, unhealthy?
In recent years, due to changes in the concept of life, many people's impression of kimchi has changed from "delicious, cheap and convenient" to "carcinogenic, high salt and unhealthy". Is kimchi really inedible?
First of all, it must be admitted that in terms of nutritional value and health, kimchi is indeed far inferior to fresh vegetables.
On the one hand, the pickling process causes a large loss of vitamins in fresh vegetables, and on the other hand, no matter which method is used to make kimchi, a lot of salt is inevitably used, and eating kimchi in large quantities for a long time does increase the risk of high blood pressure. In addition, a long-term high-salt diet is also a risk factor for stomach cancer.
However, the harm caused by the high salt of kimchi also depends on how much we eat and how often we eat it. As long as the frequency and quantity of food can be controlled, the adverse effects of high salt can also be well reduced.
Secondly, another health concern of kimchi is nitrite. During the pickling process of vegetables, the nitrate in them is converted by bacteria to nitrite, which can be further converted into nitrosamines in the stomach, which is a carcinogen that can easily cause cancer of the digestive tract.
Although nitrosamines cause cancer, it does not mean that kimchi is a "poison". The nitrite content varies with the length of curing time.
According to experimental calculations, the nitrite content in pickled vegetables first gradually increases, reaches a peak in about one week to two weeks of pickling, and gradually decreases to within the national limit standard after 20 days, and can usually reach 3 mg/1000 grams after 30 days, which meets the requirements of our national "National Food Safety Standard Contaminant Limit in Food (GB2762-2017)" on nitrite content in pickled vegetables - no more than 20 mg/1000 grams. This means that we can reasonably avoid nitrite hazards based on the curing time.
3
Kimchi contains lactic acid bacteria
Is it a healthy "fermented product"?
There is also a saying about kimchi that it is called an "intestinal health supplement" and improves the intestinal flora. Is there any truth to this statement?
Experiments have confirmed that fermented foods such as kimchi can supplement intestinal probiotics and play a role in reducing the body's inflammatory response. However, considering that these probiotics are mainly found in kimchi soup, and kimchi itself is high in salt, it is still not recommended to eat more kimchi to obtain intestinal probiotics.
We can get probiotics through healthier fermented foods like yogurt, cheese, etc. Friends with normal intestinal flora do not need to supplement too many probiotics. Just pay attention to a balanced diet and eat more fresh vegetables and whole grains rich in dietary fiber, which can also promote the healthy growth of intestinal flora.
4
Eat kimchi like this
Lower health risks
It can be seen that if you want to eat kimchi with peace of mind, it is nothing more than finding a balance between delicious and healthy. Here are some ways to reduce the health risks of eating kimchi:
1. Homemade kimchi can be fermented by purchasing pure lactic acid bacteria powder directly. Reduces the likelihood of nitrite production by avoiding the presence of miscellaneous bacteria.
2. Extend the fermentation time: Try to marinate for 20 days to 1 month before starting to eat.
3. Do a good job of sealing: Whether it is during pickling or after eating, you should pay attention to sealing to avoid the entry of miscellaneous bacteria.
4. Low-temperature refrigeration: After eating, low-temperature refrigeration can be used to delay the production rate of nitrite.
5. Don't buy loose kimchi from vendors. These informal products may have problems such as insufficient curing time and impure fermentation cultures, resulting in high nitrite levels and increased health risks.
6. Eat a small amount and rinse with water before eating.
7. Use kimchi instead of salt for stews or stir-fries. This practice can not only be paired with more fresh vegetables to supplement the lack of vitamins in kimchi, but also have the effect of "salt reduction", killing two birds with one stone!
5
Which kimchi is more recommended?
Over the years, there have been more and more patterns of kimchi. From "overnight pickles" to "bath pickles" (also known as diving pickles), which of these kimchi is more recommended than traditional kimchi?
The so-called "overnight pickles", like "bath kimchi", are kimchi that can be eaten after only a few hours or overnight. This is very different from the traditional pickling time of a month or even longer, which is more convenient.
In terms of flavor, it must be the traditional kimchi that has been marinated for a longer time, after all, the fermentation process can produce more flavor substances such as acids, esters, and alcohols. Of course, some people feel that although the sour aroma of "bath kimchi" is not rich enough, it is better than being refreshing and crispy.
From the perspective of food safety, the nitrite content of traditional kimchi pickled for more than a month is already very low, usually below the safety limit set by the national standard, and moderate intake will not pose a threat to health.
However, due to the very short pickling time of "overnight pickling" and "bath kimchi", nitrite has not yet had time to be produced in large quantities. In addition, this kind of short-term kimchi is often added to liquor and stored at low temperature and refrigerated, which is not conducive to the reproduction of miscellaneous bacteria and the production of nitrite. Therefore, it is also safe under the condition that the curing hygiene can be guaranteed. However, this kind of kimchi is best eaten within 2~3 days, otherwise the nitrite content will gradually increase.
From the perspective of salt content, traditional kimchi has a high salt content, but "overnight stains" and "bath kimchi" are not necessarily lower. In order to be easy to pickle and add flavor, this type of kimchi first uses a lot of salt to "kill" the water in the vegetables, and adds salt and a lot of sugar when pickling (in some recipes, 100 grams of sugar is used to marinate two white radishes and one cucumber). If you eat too much at one time, it will also increase the intake of salt and sugar, which will adversely affect the stability of blood pressure and blood sugar.
It can be seen that these two types of kimchi, as long as you pay attention to the hygiene of the pickling time and pickling process, there should be no big problem in terms of safety, and the deliciousness also has its own characteristics. The only thing to note is that it is wise to control your intake and only try it as a side dish once in a while.