Application of betaine instead of methionine in production
Betaine, also known as trimethylglycine, chemical name is trimethylaminoglycine, molecular formula is C5H11O2N, is a quaternary amine alkaloid. It has three indispensable substances in animals-active methyl group, which has 2 methyl groups more than methionine, and is a high-efficiency methyl donor. Under the action of betaine?homocysteine methyltransferase, the methyl group can be supplied to homocysteine to form amino acids. Therefore, in theory, betaine can replace the more expensive methionine to reduce feed cost. Betaine was discovered in Europe, mainly in molasses, but its efficacy was confirmed in the 1970s. With the development of biology and aquaculture, betaine will soon be widely used at home and abroad.
1. Physicochemical properties of betaine
Betaine is a white prismatic or leaf-like crystal with a melting point of 293°C and a sweet taste. The hydrated form of betaine is soluble in water, soluble in methanol and ethanol, and slightly soluble in ether. It has strong moisturizing properties, and is easily hygroscopic and deliquescent at room temperature. Betaine is very stable, resistant to high temperature of 200 ℃, and has strong antioxidant properties. The toxicity test proved that betaine is drug-free.
2. The production process of betaine
1. Natural substance extraction method: the betaine content in the waste molasses produced in the sugar making process reaches 3% to 8%, which is the main raw material for betaine extraction. In the 1920s, there were foreign reports on the extraction of betaine from waste molasses. From the 1960s to the 1970s, the extraction method was vigorously developed, and there were many reports on the ion exchange extraction method, and the recovery rate of betaine was about 70%. Finland established Calter, the only company in the world that produced and sold betaine at that time. In the early 1980s, Finnish scientists (HeikkiOHeikkila, etc.) used chromatography to create an exclusion extraction method, which could produce betaine anhydrous or monohydrate with a purity of about 98%. The rate of production is 79% to 80%, which reduces production costs and avoids environmental pollution. At the same time, the Japan Beet Sugar Co., Ltd. Research Institute also reported this method. In China, units such as Zhejiang Huangyan Glory Chemical Plant and Shenyang Petrochemical Research Institute have also extracted betaine and betaine hydrochloride with a purity of more than 97% from beet molasses.
2. Chemical synthesis method: In recent years, with the increase in the demand for betaine in the breeding industry, it is no longer sufficient to extract betaine from beet molasses. People have successfully studied the method of chemical synthesis of betaine. Using sodium chloroacetate and trimethylamine as raw materials, it is easy to synthesize betaine in an aqueous solution at atmospheric pressure. However, because the synthetic method consumes chemical raw materials, the production cost is much higher than that of the extraction method. The Feed Research Institute of the Chinese Academy of Agricultural Sciences has also artificially synthesized crystalline and liquid betaine. The properties of natural betaine and chemically synthesized betaine are the same, but the content and flavor are different. Anhydrous or monohydrate betaine can be produced by the above method, and betaine hydrochloride can be obtained by adding an appropriate amount of hydrochloric acid to crystallize and filter the concentrated betaine solution.