Effect Of Starter And Actinidin On The Quality Characteristics Of Horse Meat Sausage

In order to improve the quality of horse meat sausage,this study uses fresh horse meat and horse fat as raw materials,and added LyocarniPRO-MIX5 mixed starter(Staphylococcus xylosus,Lactobacillus paraplantarum,Lactobacillus sakei)and actinidin and various excipients to make horse meat sausage under controlled temperatures and times.The experimental designs contain 3 groups,one control group(CK group)and two experimental groups;and the two experimental groups added 2%of the starter(group A and group B),in group B 0.05%actinidin was added and fermented under the corresponding conditions to study the effects of the starter and actinidin on the quality index,protein degradation,microbial phase change and volatile flavor changes of horse meat sausage,so as to provide a theoretical basis for the industrial production of horse meat sausage.The main findings are as follows:1.Study the effects of starter and actinidin on the quality indicators of horse meat sausage.The pH value,water activity(Aw),water content,color difference and thiobarbituric acid(TBA)values of each group of horse meat sausages during fermentation and processing were used as quality indicators,and combined with sensory evaluation,study the effects of starter and actinidin on the quality characteristics of horse meat sausage.The results showed that compared with the CK group,the starter treatment group(group A)significantly reduced the pH,Aw and TBA values of the horse meat sausage,accelerated the decrease of moisture content,and increased the brightness value(L*)and redness value(a*),the late yellowness value(b*)decreased slightly.Compared with the group A,the starter and actinidin treatment group(group B)increased the pH value,decreased the Aw,and accelerated the decrease of moisture content,but had little effect on a*,L*,b*,and had no significant effect on TBA value.The sensory evaluation of the products showed that the taste of group B horse meat sausage was better than that of group A and CK group.2.Study the effects of starter and actinidin on protein degradation of horse meat sausage.The total nitrogen(TN)content and non-protein nitrogen(NPN)content of each group of horse meat sausages during fermentation were used as protein degradation indicators,and analyze its effects on muscle protein degradation by the Sodium Dodecyl Sulfate-Polyacrylamide Gel Electrophoresis(SDS-PAGE).The results showed that the TN content of each group was 3.09 g/100 g after enema(0 d),and the TN content of CK group,A group and B group were 3.41 g/100 g and 3.85 g/100 g,4.15 g/100g respectively after fermentation(28 d).28 d the NPN content of group CK,group A,group B were 0.42 g/100 g,0.52 g/100 g,0.65 g/100 g;and compared with 0 d NPN content(0.22 g),CK group increased by 1.9 times,group A increased by 2.4 times,and group B increased by 2.9 times;indicating that starter and actinidin had significant effects on TN and NPN contents of horse meat sausage;SDS-PAGE electrophoresis showed that during the whole processing,the sarcoplasmic proteins of group A and group B gradually degraded,and the macromolecular bands changed significantly.The starter significantly promoted the degradation of sarcoplasmic protein and myofibrillar protein in horse meat sausage(p<0.05),actinidin had a significant effect on sarcoplasmic protein(p<0.05)and was larger than the starter,but had little effect on myofibrillar protein.3.The effects of starter and actinidin on the dynamic changes of microorganisms in the fermentation process of horse meat sausage were studied by PCR-DGGE analysis.The results showed that the type and quantity of microbes in the process of fermentation and processing were dynamically changed.The starter and actinidin had certain effects on the bacterial phase change of horse meat sausage,and the effect of the starter was greater.4.HS/SPME-GC/MS technique was used to study the changes of volatile flavor substance in the horse meat sausages products(28 d)of each group.The results showed that a total of 92 volatile flavor substances were retrieved from the experiment,including 29 kinds of hydrocarbons,24 kinds of aldehydes,6 kinds of ketones,9 kinds of heterocyclics,10 kinds of alcohols,3 kinds of acids,6 kinds of amines,2 kinds of esters and 3 kinds of other substance;the aldehyde content is the highest among all volatile flavor substances,and the relative content in group A and group B is higher than that of CK group,especially the content of hexanal,phenylacetaldehyde and furfural higher than that of CK group,and the content in B group was the highest.It can be seen that actinidin and starter can effectively improve the flavor of horse meat sausage,and the contribution of actinidin is large.