The Effect Of Composite Preservation Technology On The Physico-Chemical Characteristics And Bacterial Community Of Chicken Meat

Chicken meat is not only tasty but also rich in nutrition,and because of its characteristics of high protein and low fat,it is deeply loved by consumers.Along with the raising of people’s living standards and consumption level,the market demand for chicken meat is also increasing day by day.However,since the continuous outbreak of H7N9influenza,many places in China have issued policies related to the ban on live poultry trade,and the consumption structure of chicken meat has changed from the traditional live chicken trade to centralized slaughtering and a cold and fresh market.Therefore,the quality of fresh chicken meat and its shelf life have received more and more attention.However,most of the fresh chicken meat sold on the market at present only adopts a relatively simple packaging method,which is single and has a poor preservation effect.The relatively backward preservation technology has seriously restricted the development of the chicken meat industry.Based on this,this paper takes fresh chicken meat as the research object and combines superchilling,compound antibacterial agent,and MAP technology to study the effect of the composite preservation technology on the physico-chemical characteristics and the number of dominant spoilage bacteria of chicken meat by measuring the TVB-N value,TBARS value,cooking loss,TVC,Pseudomonas count,and LAB count during storage.High-throughput sequencing technology is then used to explore the effect of the composite preservation technology on bacterial diversity and flora structure.The results of the study are as follows:1.Through single-factor tests,the optimal preservation concentrations of the three antibacterial agents were comprehensively screened out,namely lactic acid（0.09%,0.12%,and 0.15%）,lysozyme（0.06%,0.09%,and 0.12%）,and Nisin（0.09%,0.12%,and 0.15%）.Based on the single-factor test,a three-factor,three-level orthogonal test was conducted to determine the optimum ratio of the compound antibacterial agent:0.12%lactic acid+0.09%lysozyme+0.09%Nisin.2.By measuring the TVC,p H,and cooking loss in six groups of MAP chicken meat,the three groups with the best preservation effect were comprehensively selected:Group C（30%CO₂/70%N₂）,Group D（40%CO₂/60%N₂）and Group G（15%O₂/30%CO₂/55%N₂）.3.The combination of the selected compound antibacterial agent（0.12%lactic acid+0.09%lysozyme+0.09%Nisin）and the MAP treatment groups（Group C,Group D and Group G）were applied to the preservation of fresh chicken meat under superchilling conditions to explore the effect of the composite preservation technology on the physico-chemical characteristics of chicken meat.It was found that Group 1（0.12%lactic acid/0.09%lysozyme/0.09%Nisin+30%CO₂/70%N₂）was better than the other groups in maintaining steady physico-chemical characteristics（including TVB-N values,TBARS values,and p H values）during the storage period,except for Group 3（0.12%lactic acid/0.09%lysozyme/0.09%Nisin+15%O₂/30%CO₂/55%N₂）,which was more beneficial for preventing the chicken meat from discoloration.4.By measuring the TVC,Pseudomonas count,LAB count,and Enterobacteriaceae count in the chicken meat during storage,it was found that Group 1 was more effective in inhibiting spoilage bacteria than the other groups.5.By exploring the effects of composite preservation technology on bacterial communities,it was found that Serratia spp.,Pseudomonas spp.,Delftia spp.,Lactococcus spp.,and Carnobacterium spp.are ubiquitous in the process of meat spoilage.The MAP treatment complicates bacterial succession process in chicken meat.During the storage period,Pseudomonas spp.and Serratia spp.were the dominant flora in the CON group,while Serratia spp.and Delftia spp.were the dominant flora in the MAP treatment group.Compared with the CON group,Group 1 inhibited the highest number of bacterial flora,which mainly included 11 genera of unclassified-Enterobacteriaceae spp.,Aeromonas spp.,Exiguobacterium spp.,Sphingomonas spp.,and Shewanella spp..In summary,the Group 1 composite preservation technology（0.12%lactic acid/0.09%lysozyme/0.09%Nisin+30%CO₂/70%N₂）had the best preservation effect compared to the other groups,extending the shelf life of the chicken meat to over 24 days.The composite preservation technology used in Group 1 not only maintains the stability of chicken meat quality（including TVB-N values,TBARS values,and p H values）throughout the storage period but also effectively inhibits the growth and multiplication of spoilage bacteria（Pseudomonas,LAB,Enterobacteriaceae,Aeromonas spp.,Exiguobacterium spp.,Sphingomonas spp.,and Shewanella spp.）in the chicken meat.