Nutritional components of germ
In wheat grains, germ only accounts for 2%, and the rest are bran and endosperm. Although the share of germ is very small, it contains a high concentration of various nutrients that sustain life movement. Such as fat, protein and various enzymes, vitamins and minerals. Hal, a famous American nutritionist, pointed out that half a cup of germ contains protein equivalent to the protein of four eggs, and the vitamin B 1 is 3.5 times of the daily human needs. About 60% of vitamin B 1 in a wheat grain is concentrated in the germ. In addition, it also contains 10% oil. Oil contains a lot of vitamin E and papain, which are called rejuvenation vitamins. In addition, vitamin B6, which is rarely found in other foods, also exists in germ in large quantities.
From the table 1~3, we can see the contents of various components in the germ.
Extraction method of germ
At present, there are three main methods for extracting wheat germ:
1. Prototype germ
Wheat? Selected? Impact peeling germ? Screening? Wind selection? Coarse? Screening? Prototype germ
2. Flat germ
Wheat? 1B, 2B (roller mill)? Select coarse particles? Crush lightly? Screening? Strong pressure? Screening? Flat germ.
3. Pure germ powder
Rough flat germ? Broken? Screening? Heating? Smash? Screening? Germ powder.
The obtained germ is degreased, refined, roasted, crushed, screened and made into various required products. At present, the products of wheat germ can be divided into the following categories:
A. full-fat germ
B. Defatted germ
C. Use of wheat germ oil germ Wheat germ is an excellent food additive. Adding germ to bread, cakes and other foods will not only greatly improve its nutritional value, but also improve its flavor and increase appetite. As nutritional supplementary food and seasoning, it can also be added to various dishes. In addition, germ can also be used as a substitute for skim milk powder with high nutrition.
In addition to food applications, it also has extraordinary functions in medicine, beauty, feed and so on.
Escherichia coli plays an important role in people's health and aging. Regular consumption of germ can promote the development and growth of Escherichia coli, especially Bifidobacterium. In addition, the edible fiber contained in germ can not only reduce the cholesterol content in blood, but also prevent intestinal embryos.
Crude germ is also a good feed for livestock, especially in fish farming.
Preservation method of germ
When wheat germ is attached to the seed, its various properties are relatively stable. Once processed and separated, due to the damage, the enzymes in the germ become active sharply, and fat oxidation occurs, which is easy to corrupt the germ. Although there are many anti-corrosion measures, the most commonly used effective method is roasting, that is, roasting germ to inactivate the enzyme. Followed by low temperature drying method. After the embryo is roasted, the moisture content is reduced due to enzyme inactivation, which greatly prolongs the shelf life compared with raw embryo. However, the hygroscopicity is still very strong, so the products should be vacuum packed in airtight containers or filled with nitrogen, carbon dioxide, oxygen absorbent, etc., and stored in low temperature and dark places. At present, the shelf life of full-fat germ is 1 month, the shelf life of low-temperature germ is 3 months, and the shelf life of defatted germ is 6 months.