Research On Quality Changes Of Slaughtered Mutton By Using Different Conditions

In this study, the mutton of xinjiang area were used as the research object. The slaughtered muttonwere treated by using electrical stimulation and carcass suspension treatments, use nontreatment mutton asblank control, then stored at4℃for16days. During the storage, detect the shear force values, rate of pH,cooking loss, drip loss, TVBN, POV and the color of longissimus muscle every24hours. The data wereanalysed by using SPASS statistical package. Electrophoresis and Tissue section technique were used toanalyse the change of biochemical and micro structure of the different treatment groups during storage.Finally, the PCR-DGGE technique were used for different treatment groups of mutton during storage in themicrobial changes do research.The main results come out as follows:1. During storage, by detected the physical indicators, the conclusions are as follows: carcass suspensiontreatments and electrical stimulation treatment both can improve the tenderness of mutton after slaughter.the electrical stimulation group can decrease the pH value rapidly at the beginning of the storage, so it canshorten the maturity time of mutton; The TVBN value and POV value of the electrical stimulation groupwere Significantly increased in the end of storage, fat oxidation were increased, the corruption of muttonwere deepening; Electrical stimulation treatment and carcass suspension treatments had no obvious effecton the color of mutton; Electrical stimulation treatment and carcass suspension treatments had a detrimentaleffect on water holding capacity; Through the sensory evaluation, electrical stimulation treatment andcarcass suspension treatments both can improve the edible quality and the tenderness of mutton, butelectrical stimulation treatment can accelerate the corruption of mutton, it is not conducive to long-termstorage.2. Detected the MFI and activation of calcium protease activity of longissimus muscle of differenttreatment group every48hours during storage, and combined with SDS-PAGE electrophoresis to analysethe degradation degree of protein, then the transmission electron microscope was used to observe the breakof Z-disk of different treatment group at different time. the conclusions are as follows: electrical stimulationtreatment can accelerate the degree of myofibril small pieces of mutton, improved the activity of calciumactivated protease, promote the degradation of myofibril protein effectively, and it can also accelerate thebreak of Z-disk which between the sarcomere, improved the tenderness of mutton in short time; carcasssuspension treatments can also increased the degree of myofibril small pieces and the degradation ofprotein, but the effect was lower than electrical stimulation treatment.3. PCR-DGGE technique were used to reveal the dynamic changes of predominant bacterial in differenttreatment groups during storage, the result showed that: During the early storage, the pollutivemicroorganism of initial stage have higher much shape in different groups, but as storing the increase oftime, its advantage was replaced gradually by few rotten bacterium. the difference of microbial florabetween different groups was significantly, in the late storage, the Staphylococcus sp. was the predominantbacteria in carcass suspension treatment group, The predominant bacteria of electrical stimulation groupwas Pseudomonas sp.