in the eyes of Chinese people, whether it is cooking or cold sauce, adding a few drops of soy sauce can always play a “finishing touch” role. However, using more doesn’t mean you really understand. In this issue, life times invited Ji Fengdi, associate researcher of Beijing Institute of food industry and doctor of food brewing from school of food science and nutrition engineering of China Agricultural University, to show you the secrets of soy sauce. The aroma of
is stronger than that of “wheat bran”. Soy sauce is mainly made of protein and starch. Soybean and soybean meal (defatted soybean) are commonly used protein raw materials, while wheat and wheat bran (wheat husk) are commonly used starch raw materials. Generally speaking, whether soybean or soybean meal is used, the influence on the quality of soy sauce is not great (soybean is slightly better than soybean meal). However, compared with wheat bran, wheat is more abundant in sugars, so the aroma is more rich and mellow in the later fermentation. Because the use of wheat bran will save costs, many soy sauce is brewed with this raw material. Consumers should carefully look at the ingredient list when choosing, and try to choose products with soybean and wheat ingredients.
and “high salt dilute state” fermentation had good nutrition. According to the different fermentation conditions, soy sauce brewing technology is divided into “high salt dilute state” fermentation and “low salt solid state” fermentation. Low salt solid-state fermentation temperature is higher, production cycle is shorter, basic 28 days can produce finished products. This way of fermentation can accelerate the production of soy sauce and improve the output, which is also the way adopted by most soy sauce manufacturers in China. The temperature of high salt dilute fermentation is relatively low, the fermentation time is longer, and the yield is relatively low. However, this fermentation method can make the raw materials fully fermented and synthesize more flavor substances. The soy sauce brewed by this method has a more mellow taste and rich nutrients. When consumers choose, the fermentation method of soy sauce can be found in the column of “product standard number” on the food label. Whether
are fresh or not depends on “amino acid nitrogen”. During soy sauce fermentation, protein raw materials are decomposed into amino acids by microorganisms, so the content of “amino acid nitrogen” reflects the level of fermentation to a certain extent. Whether a bottle of soy sauce is fresh or not depends on the content of amino acid nitrogen. According to the national standard, this index must be indicated on the label of soy sauce products. The minimum amino acid nitrogen content of qualified soy sauce should not be less than 0.4g/100ml. At present, the content of amino acid nitrogen in domestic super grade soy sauce is 1.2g/100ml. Of course, the higher the content of amino acid nitrogen is, the better. At present, many soy sauce products are added with MSG and nucleotide based fresheners. Because monosodium glutamate belongs to amino acid, the amino acid nitrogen content of this product is also particularly high. Consumers should pay attention to it when choosing.
do not contain preservatives and may contain high salt. In order to attract consumers, many products have made “no preservative” brand name. In fact, according to industry practice, soy sauce will generally add preservatives, usually potassium sorbate, sodium benzoate or sodium dehydroacetate. Because the taste of soy sauce is getting better and better, but because of the lack of salt, it can not fully inhibit mold and bacteria. Preservatives are added in order to ensure the health of consumers. When added according to the amount permitted by the state, it will not cause adverse effects on human body, and will make the product quality more stable. Some products claim absolutely no preservatives, but it may not be reassuring. One possibility is that too much salt is added to the product, and eating too much salt will harm the health of consumers; if the taste is too salty and there is no preservative, then the safety can not be guaranteed. ▲