Effect Of Startert On Sensory Quality And Flavor Of Fermented Mutton Jerky

In this experiment,lactic acid bacteria with excellent characteristics which were selected which with commercial starter 302 were served as fermentation agents for the fermented mutton jerky.The natural fermentaion was used as a control group,the sensory quality,odor and microbial structure of fermented mutton were measured by electronic tongue,gas chromatography mass spectrometry and PCR-DGGE,and the effects of different starter on the flavor and microbial structure of fermented mutton were analyzed to provide a theoretical basis for the screening of excellent starter.The research results are as follows:Through further screening of 46 strains of lactic acid bacteria isolated from three traditional fermented meat products,After salt tolerance,nitrite resistance,acid resistance,Finally TR1-1-3 and RQ3-1-7 were choosed as the starter,It was confirmed by 16S rDNA identification that TR1-1-3 was Lactobacillus helveticus and RQ3-1-7 was Pediococcus pentosaceus.The production of fermented dried meat was carried out by using TR1-1-3,RQ3-1-7 and standard starter 302 as a starter and natural fermentation as a control group.the pH of the starter group rapidly decreased to below 5.0,and the pH of the starter group was significantly lower than that of the control group(p<0.05);At the mature stage,the water activity of the starter group could be reduced to below 0.75,which was significantly lower than that of the control group(p<0.05),and the 302 and TR1-1-3 groups were significantly lower than the RQ3-1-7 group(p<0.05);during the whole fermentation stage,the e value of the 302 group was higher than the other two groups,and the TR1-1-3 group was higher than the RQ3-1-7 group;The addition of starter can improve the hardness,elasticity,chewiness and recovery of the product;the nitrite content of the starter group was lower than 0.9 mg/kg,significantly lower than the control group 1.38 mg/kg(p<0.05).After mutton dry fermentation,the number of lactic acid bacteria in the starter group could reach 109 CFU/g,which was significantly higher than that of the control group of 107 CFU/g(P<0.05).The change trend of the total number of colonies was consistent with the change trend of lactic acid bacteria number;The coliform group in the starter group was in the range of 2.20-2.50 lgCFU/g,which was significantly lower than that of the control group of 3.59 lgCFU/g(p<0.05).The addition of the starter can effectively increase the type and content of the flavor substances in the product.During the whole fermentation stage,the content of the flavor substances rised and then decreased,and the flavor substances of the various groups in the finished stage,especially the types and content of aldehydes,alcohols and esters was 302 groups>RQ3-1-7 group>TR1-1-3 group>control group;The taste richness and salty taste of the starter group was significantly better than that of the control group(p<0.05);when the dominant bacteria group was lactic acid bacteria,it affected the detection of alcohol and ester flavor substances,when the dominant bacteria was lactic acid bacteria,staphylococcus and uncultured bacteria,it affected Detection of aldehyde substances.