The Enzymatic Hydrolysis Of Beer Yeast And Preparation Of Pork Flavor Essence

The crude enzymatic hydrolysate of beer yeast was obtained through the compositeenzyme hydrolysis in this study; extracting RNA in it via high temperature and weak basemethod and the yeast extraction with a high content of taste nucleotide was prepared by thetargeted enzymolysis of5’-phosphodiesterase; the Maillard reaction of hydrolysate, reducingsugar and other auxiliary raw materials was studied to prepare pork flavor essence.The autolysis process of waste beer yeast was studied to obtain the appropriate conditions;The optimal enzymatic conditions of cellulase, β-glucanase enzyme, flavor protease and yeastextract enzyme wa studied separately, and compare the effection of composite enzymatichydrolysis of them.The β-glucanase enzyme and yeast extract enzyme was selected as theoptimal compound enzymes. The response surface experiment was used to evaluate theoptimum conditions of composite enzymatic hydrolysis on the basis of DH and amino nitrogenrate. The optimal conditions were as follows:48.04℃, the ratio of yeast extract enzyme andβ-glucanase enzyme was1.11, pH5.92, under the conditions, the yeast hydrolysates with DHfor73.8%and the amino nitrogen rate of4.4%were obtained. The amino acid in the obtainedyeast was analyzed, glutamic acid, alanine, glycine, arginine and other18kinds of free aminoacid was identified, total content was38.733g/L enzymolysis liquid including essential aminoacids (EAA)/(TAA) of44.18%.The RNA in the enzymolysis liquid was obtained via high temperature and weak baseexperiment. The optimum process conditions for preparing yeast extract was determined byorthogonal experiments as follows:60℃, pH6.0, the enzyme volume of addition was0.3%,enzymolysis3.5h, under this condition obtained the yeast liquid with a the total content ofinosine monophosphate and guanosine product3017.5(mg/100g).The Maillard reaction of hydrolysate, reducing sugars, lard and other auxiliary rawmaterials was studied to prepare pork flavor essence.The optimum process conditions forMaillard reaction was determined by orthogonal experiments as follows:110℃,6.0g lard,25.0g yeast hydrolysates, reacted120min.Under this condition, the pork flavor essence with fulland strong aroma was obtained,36kinds of different compounds were identified by GC-MS,mainly include furfural,5-methyl-2-Furancarbo-xaldehyde,9-Decenoic acid, n-Decanoicacid,Tetradecanoic acid and other long chain saturated fatty acid,(E,E)-2,4-Decadienal,Octadecanal and other aldehydes materials, which contributed to the flavor of the pork essence.