Research On The Application Of Inoculation Fermentation And Enhanced High Temperature Technology In The Processing Of Wind Goose

Dried cured goose is one of the traditional air-dried poultry meat products in our country.The process of forming unique flavor in the process of processing is more complex.Protein degradation will produce different fragments of small peptides and free amino acids,which can be used as both flavor substances and important precursors of volatile flavor substances.The low air-drying temperature and short time lead to low protein degradation and poor flavor and flavor quality of dried cured goose processed by traditional technology.In this study,inoculation fermentation and enhanced high-temperature technology were introduced into the processing of dried cured goose to promote the degradation of protein in the drying period of dried cured goose from the perspective of exogenous enzymes and endogenous enzymes.Finally,the effects of the combined process of enhanced high-temperature-inoculation fermentation on the quality and volatile flavor of dried cured goose were discussed.The specific research results are as follows:1.Isolation and screening of excellent strains with high protease activity from dried cured goose products.Based on the basic standard of starter for meat products,the protease-producing ability of strains was taken as the basis of re-screening,and the protease-producing ability of strains was analyzed qualitatively and quantitatively.Finally,two strains L28 and S24 were selected as the best strains,with protease activity of 40.47 U/mL and 47.86 U/mL,respectively.Through physiological and biochemical tests and 16S rDNA sequencing,L28 was identified as Lactobacillus fermentans and S24 as Sfaphyhcoccus epidermidis.2.The effects of inoculation fermentation on protein degradation in dried cured goose was studied.The inoculation fermentation technology was applied to the processing of dried cured goose.The screened Lactobacillus fermentation L28,Staphylococcus epidermidis S24 and mixed strains(L28:S24=1:1)were inoculated into the whole goose before drying,and compared with the uninoculated group(natural fermentation)to study the effect of inoculation fermentation on the degradation of protein in the air-dried period of dried cured goose.The results showed that compared with natural fermentation,inoculation fermentation significantly increased the content of non-protein nitrogen,protein hydrolysis index,muscle fibre fragmentation index and free amino acid in the air-dried period of dried cured goose,and the total amount of free amino acid in inoculated mixed bacteria fermentation group was significantly higher than that in other groups(P<0.05),reaching 1332.6 mg/100g.Protein gel electrophoresis(SDS-PAGE)analysis showed that inoculation fermentation could promote the degradation of myofibrillar proteins in dried cured goose,and the effect of inoculated mixed bacteria fermentation group is better than other groups.3.The effect of enhanced high temperature treatment on protein degradation of dried cured goose.Enhanced high temperature treatment before drying goose meat,high temperature treatment at 40,50 and 60 C for 1.5 h(T40,T50,T60),in comparison with non-enhanced high temperature group.The effects of enhanced high temperature on endogenous protease activity and protein degradation in dried cured goose were studied.The results showed that the activities of cathepsin B,H and L in dried cured goose were significantly increased by intensifying high temperature,and then the contents of non-protein nitrogen,protein hydrolysis index,muscle fiber fragmentation index and free amino acid were increased.The total amount of free amino acid in T50 group was significantly higher than that in other groups(P<0.05),reaching 1412.1 mg/100g.Protein gel electrophoresis(SDS-PAGE)analysis showed that enhanced high temperature could promote the degradation of myofibrillar proteins in dried cured goose,and T50 group had the most obvious effect,indicating that enhanced high temperature could significantly improve the degradation of proteins in dried cured goose.4.The effect of inoculation fermentation and enhanced high temperature treatment on the quality of dried cured goose.The inoculation fermentation and enhanced high temperature technology were applied to the processing of dried cured goose at the same time.The following four groups of treatments were applied to the geese before air drying:1.5 h at 16 C,without inoculation group(CK);1.5 h at 50 ?,without inoculation group(G1);1.5 h at 16 ?,inoculation group(L28:S24=1:1)(G2);1.5 h at 50 ?,inoculation group(L28:S24=1:1)(G3).The effects of combined high temperature and inoculation fermentation on the basic quality and volatile flavor of dried cured goose were studied.The results showed that the combined process group(G3)significantly reduced the pH value and Aw value(P<0.05)and improved the product storage performance;significantly increased the L*value,a*value,hardness value and chewiness(P<0.05),and improved the color and texture of the dried cured goose;meanwhile,the total content of flavor substances in the combined process group(G3)was significantly higher than that in the other groups(P<0.05).The types and contents of flavor substances in the G3 group were 65 species and 597.1 ug/kg,respectively,and their sensory scores were the highest.Generally speaking,the strains with high protease activity were screened from natural fermentation products of dried cured goose,and then inoculation fermentation and enhanced high temperature technology were applied to the processing of dried cured goose respectively.These two processes can promote the degradation of protein during the drying period of dried cured goose.Finally,the combined treatment of enhanced high temperature and inoculation fermentation can improve the basic quality and flavor of dried cured goose,and provide certain theoretical guidance for improving the quality of dried cured goose products.