During the Northern Wei Dynasty, there was another person who was also very accomplished in diet, and that person was Jia Sixie. He compiled the Book of Qi Yaomin, which mentioned many food additives and many novel methods and means of making food, many of which were imported from foreign countries.
During the Sui and Tang Dynasties, another man named Xie Yan compiled the Huainan Jade Food Classic. He is an official in charge of the harem and the emperor's diet and is very good at it. This book also records a lot about food preparation and preservation methods, and also mentions many new food additives.
In ancient times, food additives? Not bad things, but all good things will be added to food. For example, people find that food is tasteless and sea salt is salty, so salt becomes a food additive.
Later, it was found that cinnamon can enhance fragrance, and brine can be used to make tofu because it can solidify juice. These all belong to the category of food additives, which can be added to food and are non-toxic after eating.
However, food safety problems often appeared in ancient times. In order to increase their profit margin, some unscrupulous businessmen inject water into the meat, which will make the meat heavier and look fuller. Every household needs salt. In the past, salt was not as cheap as it is today.
Some salt dealers will mix soil in salt, which won't kill people, but can gain weight. In order to make the chicken heavier, sand will be stuffed into the chicken's stomach, and only after killing the chicken will it be found that it has been cheated. Cheating money is a trivial matter. How harmful it is to eat such food in your stomach!