Research On The Functionalization Of Chicken Liver Powder

Chicken liver contains rich nutrients and is a good source of protein.However,due to its poor taste and strong fishy taste,it reduces consumers’sensory acceptability.Currently,it is mainly processed and used as a pet food attractant,which leads to the insufficient and effective utilization of nutrients in chicken liver and the waste of protein resources.Therefore,in order to further develop and utilize chicken liver,this study,based on the biological enzymolysis of chicken liver,aims to use polysaccharides to participate in the Maillard reaction process of chicken liver protease hydrolysate to modify the structure and properties of the product,thereby improving the flavor of the product and strengthening its biological function,in order to obtain a functional flavor agent and apply it to the food industry.（1）Based on the analysis the basic components in chicken liver,the enzymolysis and Maillard reaction processes of chicken liver were optimized with the degree of protein hydrolysis（DH）and the UV absorption value of Maillard reaction products（MRPs）as indicators.The results showed that chicken liver has a high protein content of 21.37 g·100g^-1,making it a good source of protein.A total of 114 volatile compounds were identified through GC-MS,with aldehydes being the main source of their fishy odor.The optimal conditions for the enzymatic hydrolysis reaction of chicken liver after optimization are:0.4%composite enzyme（trypsin:animal protease=2:1）,temperature 45℃,p H 6.0,DH up to 52.09%,total free amino acids 9.89 g·100g^-1,increased by 94.30%;The basic conditions of Maillard reaction of chicken liver enzymolysis products were as follows:adding 5%xylose,1%thiamine and 2%cysteine,reaction temperature 110℃,initial p H 8.0,reaction time 80 min.Under this condition,the absorbance values of MRPs at 420 nm and 294 nm were 0.33 and 1.00,respectively,and the formation of MRPs was the largest.（2）Based on the above preparation process of MRPs,the flavor and functional characteristics of chicken liver enzymolysis products enhanced by polysaccharide participating in Maillard reaction were used to investigate the ultraviolet absorption value,chromaticity value,fluorescence spectrum,molecular weight distribution,FT-IR spectrum,volatile flavor substances and antioxidant properties of polysaccharide MRPs.The results showed that compared with non polysaccharide MRPs（CLPHM-FP）,lycium barbarum polysaccharides（LBP）can promote the generation of browning products,fluorescent products,and>5 KDa peptides in MRPs.LBP can consume amino acids and highly bind to chicken liver hydrolysates;The content of alcohols and heterocyclic compounds in wolfberry polysaccharides MRPs（CLPHM-LBP）increased by 253.53%and 80.68%,respectively.Heterocyclic compounds had a lower odor threshold and played an important role in the formation of overall meat aroma.At the same time,the content of aldehydes decreased by 74.90%,weakening the fishy taste of MRPs,its characteristic aroma components are 2,3,5-trimethylpyrazine and 2-pentylfuran;The iron ion reduction ability,hydroxyl radical and DPPH radical scavenging rate of CLPHM-LBP increased by 36.44%,33.83%and 47.00%respectively;In addition,the inhibitory effect of CLPHM-LBP on Escherichia coli and Staphylococcus aureus increased by 71.33%and 109.57%respectively.（3）The application of polysaccharide Maillard reaction products in vegetarian chicken and meat mince was studied.Compared to the plain chicken added with CLPHM-FP,the texture performance of CLPHM-LBP plain chicken is good,with a relative increase of 35.85%in the content of heterocyclic compounds.The flavor is closer to the chicken flavor,and the shelf life can be extended by 6 days and 2 days at 4℃and 10℃,respectively.Compared to CLPHM-FP mince,CLPHM-LBP mince can slow down the decrease in mince color values（L*and a*）when stored at 4℃and 10℃,thereby protecting the color of mince and extending the shelf life of mince by 6 and 4 days,respectively;During storage at 4℃and 10℃,the growth rates of acid value,peroxide value,and TBARs value of CLPHM-LBP mince were lower than those of the control group,indicating that CLPHM-LBP can effectively delay the oxidative rancidity of mince.Therefore,CLPHM-LBP can be applied as a functional flavoring agent in food.