Brewing soy sauce is made from soybean, wheat or bran by microbial natural fermentation, and some flavoring agents are added after the process. Soy sauce is made from more than 5% brewed soy sauce by adding hydrolyzed vegetable protein solution, which has more room for flavor change. Another important indicator of soy sauce is amino acid nitrogen, and the national standard stipulates that the content of soy sauce should not be less than .4 g per 1 ml.
Skills of identifying soy sauce
At first glance, qualified soy sauce is red, bright, shiny and transparent, while unqualified soy sauce is dark and opaque.
second shake: after pouring this soy sauce into the bottle, shake it, and the foam produced by qualified soy sauce is very delicate and lasting; The unqualified soy sauce foam is relatively large and it is easy to disperse.
three hanging: gently shake it, the qualified soy sauce hangs on the bowl very well, and it has a sticky feeling. What about the unqualified soy sauce, the hanging on the bowl is not good, and it is easy to slide down again.
summary: 1. Smell aroma: The higher the quality of brewed soy sauce, the stronger the unique aroma such as sauce aroma, fat aroma and alcohol aroma, especially the sauce aroma is the most important. Fake soy sauce has no aroma, even has an odor, and inferior soy sauce has little aroma.
2. taste: it is not bitter, astringent and delicious, which is a high-quality product. On the contrary, it is a fake or inferior product similar to pickled vegetable water (commonly known as colored salted water).
3. Color: Pure brewed soy sauce is reddish brown, while hanging bowls without touching them is authentic. Although real soy sauce can be hung on the edge of the bowl, it will disappear after a few minutes, generally leaving no trace on the edge of the bowl; On the contrary, black sticks to the edge of the bowl or the bottle, leaving black marks as inferior or fake.
4. Look at the trademark: Generally, large enterprises have registered trademarks, and the packaging design is beautiful and generous. The raw materials used in soy sauce are plant protein and starch.
Plant protein is taken from bean cake after soybean oil extraction or soybean meal after oil extraction by solvent, and it is also replaced by peanut cake and broad bean. In traditional production, soybean is the main one. Wheat and bran are widely used as starchy raw materials, and some are replaced by broken rice and corn. In traditional production, flour is the main material.
The raw materials are steamed and cooled, inoculated with pure cultured Aspergillus oryzae seeds to make sauce koji, which is moved into a fermentation tank, fermented with salt water, and then the soy sauce is extracted by leaching when the fermented grains are mature. The purpose of koji-making is to make Aspergillus oryzae fully grow and develop on koji, and to produce and store a large number of needed enzymes, such as protease, peptidase, amylase, glutaminase, pectinase, cellulase, hemicellulase and so on. In the process of fermentation, the formation of taste is based on the action of these enzymes. For example, protease and peptidase hydrolyze protein into amino acids to produce umami flavor; Glutaminase turns tasteless glutamine into vulgar glutamic acid with delicious taste; Amylase hydrolyzes the sediment into sugar to produce sweetness; Pectinase, cellulase and hemicellulase can completely rupture the cell wall and make protease and amylase hydrolyze more thoroughly.
At the same time, in the process of koji-making and fermentation, yeast and bacteria falling from the air also proliferate and secrete a variety of enzymes. Pure cultured lactic acid bacteria and yeast can also be added. A moderate amount of lactic acid is produced by lactic acid bacteria, ethanol is produced by yeast fermentation, and many components such as alcohol, acid, aldehyde, ester, phenol, acetal and furanone produced by raw materials and metabolites of Aspergillus are mostly trace, but they can constitute the complex aroma of soy sauce. In addition, melanin is generated by oxidation of tyrosine in raw material protein, and melanin-like substance is generated by hydrolysis of classical mildew amylase in sediment to glucose, which reacts with amino acids, so that soy sauce produces bright and shiny reddish brown. The umami, sweet, sour, wine and ester flavors produced by a series of extremely complicated biochemical changes during fermentation are mixed with the salty taste of salt water, and finally soy sauce with unique color, flavor and flavor is formed. Teach you how to choose soy sauce
Before eating soy sauce, you should check your identity. When consumers buy soy sauce in the market, they should pay special attention to the production date and shelf life. Buy soy sauce and have a look, shake it and taste it. Look at the quality indicators and look at the colors; Good soy sauce will have a lot of foam when shaken, which is not easy to disperse, and it can also smell on the bottle mouth. Good soy sauce often has a strong sauce flavor and tastes delicious, while inferior soy sauce has only a small amount of foam when shaken, and it is easy to disperse, which tastes bitter.
look at the label first. From the raw material table of soy sauce, we can see whether its raw material is soybean or defatted soybean, wheat or bran. See clearly whether the label indicates brewing or preparing soy sauce. If soy sauce is brewed, it should be clearly marked whether it is high-salt dilute soy sauce brewed by traditional technology or fast-brewed soy sauce fermented by low-salt solid state. Brewed soy sauce can be distinguished by its amino acid nitrogen content. The higher the content of gram/1ml, the better the quality (amino acid nitrogen content? .8g/1ml is the super grade. .4 g /1 ml is the third grade, and between them is the first or second grade).
see the purpose clearly. Soy sauce should be marked for table or cooking. The hygienic indexes of the two are different, and the colony index is also different. It can be eaten directly with meals, and the hygiene index is good. If it is used for cooking, don't use it to mix cold dishes. Smell the fragrance. Soy sauce produced by traditional technology has a unique ester aroma, which is rich and mellow. It is not normal if the smell is sour, sticky and peculiar.
look at the color. The normal color of soy sauce should be reddish brown, and the color with good quality will be slightly darker. However, if the color of soy sauce is too dark, it indicates that caramel color is added, and the aroma and taste will be worse. This kind of soy sauce is only suitable for braising.
be careful to buy bagged soy sauce. There are a lot of unqualified bagged soy sauce and vinegar in the market, which are blended with water, sugar color and industrial vinegar essence. This product has a pungent smell and contains heavy metals and other substances harmful to human body.