In the process of making pickles, although the concentration of brine used for pickling is low, the osmotic pressure can't stop the activities of microorganisms, but the lactic acid produced can increase the overall acidity, inhibit harmful microorganisms and play an antiseptic role. So kimchi is very hygienic and safe.
In order to prevent the pollution of miscellaneous bacteria in the fermentation process and ensure the quality of finished products, it is required that the raw materials of kimchi should be fresh and rotten leaves should not be used.
Although kimchi is crispy and delicious, for people with weak stomach or gastric ulcer, the spicy taste of kimchi may cause irritation to the affected area, so such people should avoid eating kimchi.