Soy sauce is a condiment rich in various nutrients, made from raw materials such as soybean cake, bran, and soybeans through a series of processes including fermentation and sterilization. It is a very important ingredient in cooking. Soy sauce contains abundant amino acids and has high nutritional value.
Theoretically, soy sauce can be eaten directly, but during its production, storage, transportation, and sales, it is often contaminated due to poor hygiene conditions, and may even carry pathogenic bacteria that cause intestinal infectious diseases. The problem is more pronounced with bulk soy sauce. Experiments have shown that typhoid bacilli can survive in soy sauce for two days, and halophilic bacteria can live in it for a long time. In cloudy soy sauce with sediment and impurities, the bacterial count can be more than 100 times higher than the standard. If such soy sauce is eaten without heating and sterilization, it may cause illness. Therefore, people who like to add soy sauce directly to noodles, dumplings, tofu, and cold dishes must pay attention to food safety.
In addition, researchers have also found carcinogenic substances in soy sauce. An epidemiological survey in Taiwan found a direct correlation between soy sauce consumption and liver cancer. This is because during the fermentation process, proteins decompose and produce a large amount of amines. In the presence of nitrites, these can synthesize carcinogenic nitrosamines. Furthermore, soy sauce produced by manufacturers with poor production processes is highly susceptible to mold contamination. Therefore, from a disease prevention perspective, in addition to purchasing bottled soy sauce from trustworthy sources and avoiding bulk soy sauce, one should also try to eat soy sauce cooked rather than raw.