Study On The Effect Of Microbial Fermentation Agents On The Characteristics Of Sichuan Bacon

Traditional Sichuan bacon has apparent advantages and disadvantages: one hand, It tastesdelicious, unique flavor, easy storage; other hand, backward technology, high salt content,bacterial contamination, and residual nitrite exceeded. This project was based on thetraditional process and the concept that modernizing the traditional meat, used modernbiotechnology and chose the most suitable microbial fermentation agent to explore possibleways which can improve product quality. The main studies are as follows:Selected the fermentation agent which can make the bacon achieving optimal qualitybased on the traditional process of Sichuan bacon. Inoculated three kinds of meatfermentation agent: L. plantarum, F-1(Pediococcus pentosaceus、StapHylococcus xylosus),SM—194(Pediococcus pentosaceus、StapHylococcus xylosus、StapHylococcus carnosus、Lactobacillus sakei、Debaromyces hansenii). Results showed: The SM—194group hadmoderate pH value, awvalue, good microbial growth, and better sensory quality.Based on the sensory scores index, optimize the process conditions by the orthogonalexperiment. The optimum process conditions was:3.5%addition amount of salt,2%additionamount of sugar, tumbling time of1.5h and curing time of5d., and the factors’ influence onthe quality: amount of salt added> amount of sugar added> curing time> tumbling time.Study the effects of meat fermentation agent SM-194on the quality of Sichuan bacon.Based on the pHysical and chemical values, fat oxidation, proteolytic, texture, color,freeamino acid content, volatile components, sensory, analysed the difference betweenfermentation products and control group, also the mechanism.(1) The pH value, water content, awvalue, residues of NaNO2of the fermentation groupwere lower than the control group;(2) The acid value(AV), peroxide value(POV) and malondialdehyde content showed anupward trend. The acid value(AV) of fermentation was higher than the control group, butothers were lower, which indicated that the SM—194could promote fat to hydrolyze freefatty acid and prevent further oxidation of free fatty acids,delay the fat oxidative rancidity.(3) The content of non-protein nitrogen (NPN) and total volatile basic nitrogen (TVB-N)had an upward trend. The non-protein nitrogen (NPN) content of fermentation group washigher, which indicated that SM—194could promote protein hydrolyzate. The content of totalvolatile basic nitrogen (TVB-N) of the control group was higher, indicated that the controlgroup had higher content of amines and other basic nitrogen-containing substances and thecorruption was more serious.(4) All of the hardness, springiness, cohesiveness, gumminess, chewiness, resilience offermentation group were higher than the control group, but the adhesiveness was erratic.(5) The lightness value (L*) and yellowness value (b*) of fermentation group bacon were lower than the control group; the red value (a*) of lean meat was>0, the a*of fattymeat was less than0, and the red value of fermentation group was greater.(6) The total content of FAA of fermentation group was higher, and all of the FAA wasincreased compared with the control group, except the Asp, Thr and Tyr.(7) Except the molds, the number of the lactic acid bacteria, stapHylococcus and yeastof fermentation group was higher. Lactic acid bacteria was the dominant bacteria, the numberof stapHylococcus of two groups were low. There was no E. coli and S. Aureus in the twogroups of mature bacon products.(8)There were60kinds of volatile flavor compounds were detected from the raw meat,the control group bacon, and fermentation group bacon. There were21kinds detected fromthe raw meat,28kinds detected from the control group and48kinds detected from thefermentation group, which were alcohols, acids, aldehydes, hydrocarbons, esters, andpHenols.There was a big difference of types and quantities of types and quantities of volatileflavor compounds contained in the3sets of samples. The fermentation group had morevolatile flavor compounds and its flavor was more intense.(9) The scores of fermentation group was9, and the control group was only8.25,indicating that SM—194could improve the sensory quality of the Sichuan bacon.