Study On The Extraction Of Gliadin From Corn Gluten Water

When corn starch is produced by wet grinding,a kind of water rich in gluten is produced.This water is called corn gluten water.It is one of the main by-products in the process of producing corn starch.The content of protein in gluten is more than sixty percent,and its protein is mainly alcohol-soluble protein.The protein in corn gluten contains nearly 50 kinds of alcohol-soluble proteins..According to the research,not only are the alcohol-soluble proteins special,they are generally only dissolved in 60-95% alcohol solvents.In addition,from the microscopic structure,its specialty is also manifested in the chemical elements that constitute the molecules of gliadin and the morphological characteristics and structure of molecules.The reason why gliadin can dissolve in a high concentration of alcohol solution is that the alcohol solution can destroy the structure of the gliadin and make the structure change from regular form to the disordered network.In this case,even after removing the alcohol solvent,the gliadin can not be restored to the original form,but form a kind of form,edible films,which can also be degraded,are of uniform texture and transparent color.Because the film has these advantages,the film is used in some foreign food industry and Pharmaceutical industry,for example,some food preservative film makes use of this film,and the coating part of the capsule is mainly made up of this film.Of course,gliadin,as a new resource,has many characteristics and advantages.The production of coating materials and adhesives also involves the utilization of gliadin.First,it is necessary to obtain protein powder containing a variety of proteins from corn gluten water,and then obtain alcohol soluble protein from the protein powder.In order to separate the gliadin from the protein powder,the compound enzyme should be added to the protein powder gradually to hydrolyze the impurity protein.After every enzyme hydrolysis,filter residue should be retained.The residue was filtered into a high concentration of ethanol solution,and the gliadin was extracted in a microwave reactor.The gliadin was dissolved in a high concentration of ethanol solution.In order to precipitate the alcohol soluble protein from the alcohol solution,the concentration of the alcohol solution was reduced by water,thus the precipitation was obtained and then filtered and dried.Corn Zein can be obtained by dryness and other steps.After several experiments,the researchers concluded that the recovery rate of corn gluten water protein powder was 96% and the recovery was best when the time of separation of corn bran water was maintained for 20 minutes and the rotation speed was 3000 r/min.The optimum extraction conditions of zein were as follows: the concentration of ethanol was 75%;the pre-treatment PH was 6;the reaction time of the enzyme preparation was 2 h;the extraction temperature was 70;the extraction time was 120 s,and the output power of microwave was 400 W.In actual industrial production,when ethanol soluble protein is extracted by corn gluten water,the technological conditions take into account the factors such as maneuverability,environmental cost,time cost,energy cost and other factors.The technological indexes are slightly changed.The rotational speed of the recovery of corn protein powder is 2900 rpm,and the separation time is 20 min.The optimum conditions for extracting zein in industrial production are as follows: ethanol concentration is 75%,PH is 5.8 ~ 6.2,the reaction time of enzyme preparation is 1.8 h,extraction temperature is 70,extraction time is 110 s,microwave output power is 400 W,and the ratio of material to liquid is 1:9.8.The innovation points of this article:1.We provides step-by-step enzyme treatment instructions for extracting gliadin from corn protein powder,which can significantly reduce product impurities and increase product purity.2.The method of microwave extraction can not only use lower cost to produce high purity zein finished product,but also improve the recovery rate of gliadin.In addition,this method also has the characteristics of short production cycle.