Study On The Preparation Of Protein Foaming Powder By Deep Processing Of Corn Protein

At present,there are alkaline and enzymatic methods to prepare corn protein foaming powder using corn protein as raw material at home and abroad.Although the alkali method is simple and easy,there are many insurmountable shortcomings.Although the enzymatic method can solve the disadvantages of high ash content and deep color,it has the problems of complicated process,long hydrolysis time,low efficiency,difficult to control the degree of hydrolysis and low yield,and it is difficult to achieve industrial production.In this paper,corn protein foaming powder was prepared by a new enzymatic method,which solved the problems of long hydrolysis time,low efficiency,difficult to control the degree of hydrolysis,low yield and so on.At the same time,it can significantly reduce the ash content and color of the product,and improve product quality.The specific contents of the study are as follows:1.Corn yellow powder was treated by double enzyme method.The results of single factor test and orthogonal test between two enzymes showed that:First,cellulase was used,thenα-amylase was used to obtain pale yellow corn protein powder,the recovery rate of dry-based products was 68.6%,the content of dry-based protein was 89.9 and the recovery rate of protein was 96.1%.The protein content could reach 80.0%when the content of water was 10%.The optimum treatment conditions ofα-amylase were as follows:T=65°C,p H=6.5,enzyme concentration=0.8%,time=1.0 h,ratio of material to water=1:4,The optimum treatment conditions of cellulase:T=50°C,p H=5.0,enzyme concentration=0.6%,time=3.0 h,ratio of material to water=1:3.2.With concentrated protein as a raw material,using the improved water solubility and foamability of the protein as indicators,single factor and orthogonal experiments were used to optimize the enzyme species and various reaction conditions,and protein recovery and foaming performance were used as index.The following conclusions were obtained:The optimal conditions for protein pretreatment denaturation were as follows:temperature 45°C,sodium sulfite addition 6%,treatment time 30 min;the optimal conditions for preparation of corn protein foaming powder by papain hydrolyzed corn protein were as follows:temperature 60°C,p H 6.5,ratio of material to water 1:6,enzyme dosage 0.3%,treatment time 5 hours,product indicators:The recovery rate of dry-based products is 55.3%,product foaming height is 760%,water loss rate is 26%.The optimum conditions for the preparation of corn protein foaming powder with alkaline protease as catalyst are as follows:temperature 55℃,p H 10,enzyme content0.1%,ratio of material to water 1:5,hydrolysis time 5 hours.The test was repeated under this condition,the recovery rate of dry-based products was 64.8%,the product foaming height was 660%and the water loss rate was 20%.Papain and alkaline protease compound hydrolysis of corn protein to prepare corn protein foaming powder under the following conditions:temperature 55℃,ratio of material to water 1:6,p H adjusted to 10,adding 0.1%alkaline protease for hydrolyze 2 hours.The p H was adjusted to 6.5,and 0.3%papain was added to hydrolyze for 3 hours.After inactivating the enzyme,it was filtered,concentrated,and dried to give a product whose technical index was:the dry basis recovery rate was 67.8%.The height is 680%and the water loss rate is 21%.This program is the best solution.3.The pilot and scale-up tests was carried out in a 2M~3 reactor.The yield of corn protein concentrate,protein content and foaming powder were compared with the yield of corn protein concentrate,protein content,foaming height,water loss rate and so on.the yield of corn protein concentrate is over 65%,the protein content of the product is more than85%,and the yield of corn protein foaming powder is more than 65%,which is about twice as high as that of the current research.Foamed powder product corresponds to a raw material yield of 43.2%.