Although the old soup or broth has been circulated for hundreds of years, water and new ingredients will be added every time the remaining soup is used, which can dilute the concentration of nitrite, and the old soup or broth will be heated repeatedly every day, which can kill possible pathogenic bacteria. Therefore, a pot of soup in this old shop will continue to be used, and people will generally not affect their health.
Brine contains magnesium chloride, which is one of the minerals needed by human body. Proper intake is beneficial to the human body. But if ingested in large quantities, it will cause poisoning. Old bittern used in some old shops will constantly add new water, new ingredients and condiments, so it is equivalent to drinking part of a glass of water and then adding that part of water. In this process, harmful substances such as nitrite and heavy metals in the old brine will be continuously diluted.
Moreover, the old brine is boiled and heated every day, and microorganisms such as bacteria and viruses are difficult to survive, so the old brine will not harm human health. However, it has also been suggested that people in the tofu shop still order tofu with brine, which will not harm their health. Although the soup stock, broth and old brine have been used for such a long time, they will not endanger people's lives and health, and even if a small amount of toxic and harmful substances are produced, they will not endanger their lives. Don't worry too much.
Extended data:
The longer the broth is preserved, the richer the aromatic substances, the stronger the fragrance, the greater the umami taste and the more beautiful the flavor of cooked meat. More than ten kinds of drugs such as Amomum villosum, Amomum cardamom, Amomum Tsaoko, Pericarpium Citri Tangerinae, Cinnamomum cassia, Clove, Alpinia officinarum, Magnolia Officinalis and Fennel are added in the marinating process, which is not only delicious, but also nutritious, and has the functions of invigorating stomach, smoothing qi and appetizing.
People's Daily Online-Will there be toxic substances when brine is cooked for a long time?
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