Effect Of Modified Atmosphere Packaging On The Preservation Of Chinese Spiced Beef

Abstract:As one of the most characteristic of Chinese traditional meat products,Chinese Spiced Beef because of its short shelf life and flavor deterioration problem were seriously affected the development of the modernization and internationalization.In order to solve those problems,this paper mainly studied the fresh-keeping effect about Chinese Spiced Beef in the MAP of different gas components and ratio（vacuum-control,20:80CO₂/N2,40:60CO₂/N2,60:40CO₂/N2,80:20C02/N2,5:70:25O₂/CO₂/N2,35:40:25O₂/CO₂/N2）under 25℃,with Sensory evaluation,total bacterial count,electronic nose,TBARS,TVBN,pH,color as the evaluation index,and analyzed the difference of the products in the preservation of MAP and vacuum packaging.The results showed that,group（5:70:25O₂/CO₂/N2）and（80:20CO₂/N2）could be stored 8-10 days（total bacteria are respectively 4.70-5.08 and 4.67～5.04 log CFU/g）,and compared with vacuum packaging（total bacteria:6.03～6.69 log CFU/g）extending at least 30%on the shelf life.TVBN values（23.42mg/100g,21.98mg/100g）,TBARS（0.31 mg/100g,0.37 mg/100g）and sensory score（5,5）of（5:70:25O₂/CO₂/N2）and（80:20CO₂/N2）were significantly better than the vacuum packaging（30.59mg/100g,0.55mg/100g,3）in the end of storage time.The results show that:1)Under the condition of 25℃ storage,the characterizations of sauced beef flavor quality such as senses,smell,color difference are analyzed.Results show that the low oxygen and high carbon dioxide（5%70%70%02/C02/N2）and anaerobic high carbon dioxide（80%20%C02/N2）processing can better keep the original flavor of sauce beef.Senses in the 14th day are acceptable,and vacuum control group is not acceptable in 5th day.This shows that the effect of suitable air to keep sauced beef flavor is obviously superior to vacuum packing.2)Under the condition of 25℃ storage,the law of multiplication of the total number of bacteria that effect sauced beef safety is analyzed.Results show that the vacuum in the control group is 3-4 d earlier than low oxygen and high carbon dioxide and oxygen free carbon dioxide gas group in exceeding national standard limit in advance（4.9 log cfu/g）.The total number of bacteria in 14 d vacuum storage group is 4-5 orders of magnitude higher than that of low oxygen and high carbon dioxide and oxygen free carbon dioxide gas.This shows that compared with the vacuum packing,gas packaging of suitable gas proportion of sauced beef microorganisms has better control effect,making the products with better security.3)Under the condition of 25℃ storage,the change rule of fat oxidation and protein oxidation of TBARS value,TVBN value that characterize the sauced beef flavor deterioration is analyzed.Results show that in the 14th day,compared with the vacuum in the control group,the fat oxidation and protein oxidation of low oxygen and high carbon dioxide and oxygen free and high carbon dioxide gas group are reduced by 33%-43%,23%and 28%respectively.This shows that suitable gas adjustable handle can significantly delay the fat oxidation and protein oxidation of sauced beef,so they can keep its unique characteristic flavor better.4)Under the condition of 10℃ Storage,the indexes that character sauced beef flavor quality such as senses,smell,color difference are analyzed.Results show that under the condition of low temperature,low oxygen high carbon dioxide（5%70%70%02/C02/N2）and anaerobic high carbon dioxide（80%80%C02/N2）are better able to keep the original flavor of sauce beef,low oxygen and high carbon dioxide effect being better.On the 72th day,senses are acceptable,while those of vacuum control group in the 40th day are unacceptable.This shows that the effect of suitable gas processing in keeping sauced beef flavor is significantly better than that of the vacuum packing.And compared with room temperature（25 ℃）storage,this shows that the low temperature（10 ℃）storage is especially good for keeping sauce beef fresh.5)Under the condition of 10 ℃ storage,the total number of bacterial that effect the sauced beef safety is measured.The result analysis shows that,according to the national standard limit 4.9 log cfu/g,low oxygen and high carbon dioxide and oxygen free high carbon dioxide gas group extended 12 d more than control group.Both can be up to 40 days.On the72nd d of storage,the total number of bacteria of vacuum group is 6-7 orders of magnitude higher than that of low oxygen and high carbon dioxide and oxygen free carbon dioxide gas group.This shows that compared with the vacuum packing,gas packaging of suitable gas proportion of low temperature condition can guarantee sauce beef safety better.And compared with room temperature（25 ℃）storage,microbial proliferation of sauced beef under low temperature（10 ℃）storage is slower.6)Under the condition of 10 ℃ storage,the change rule of fat oxidation and protein oxidation TBARS value,TVBN value that characterize the sauced beef flavor deterioration is analyzed.Results show that compared with the vacuum in the control group,after storage of 72 ds,the fat oxidation and protein oxidation of low oxygen and high carbon dioxide and oxygen free and high carbon dioxide gas group are reduced by 35%-37%,27%-30%respectively.This suggest that suitable gas processing can significantly delayed fat oxidation and protein oxidation of sauced beef.7)The change rules of sensory indexes that characterize sauced beef flavor quality,the total number of bacteria that effects sauced beef safety and the fat oxidation and protein oxidation of TBARS value,TVBN value that characterize sauced beef flavor deterioration under low temperature（10 ℃）vacuum control and room temperature（25 ℃）low oxygen and high carbon dioxide,anaerobic high carbon dioxide gas group are analyzed.According to the results,within 4 days,sensory differences in three groups were not significant;within 8 days,sensory differences in vacuum control and low oxygen and high carbon dioxide group are not obvious,the effect of flavor keeping being the best;within 12 days,three senses are acceptable.The change trends of total bacterial count of three processing groups differ largely,but within 8 days,three groups did not exceed national standard limit（4.9 log cfu/g）;within 4 days,the effects of low oxygen and high carbon dioxide and vacuum control in inhibiting fat oxidation are the best;within 12 days,protein oxidation of three groups were not overweight（25 mg/g）.This shows that without cold chain,suitable gas adjustable handle can be under storage at room temperature（25℃）for at least a week,achieving the same effect with low temperature vacuum packaging,which can reduce the storage cost.The analysis based on the above research results shows that the storage temperature and gas proportion are two important factors in keeping sauce beef storage.In the six kinds of gas ratio under experiment set,with the increase of CO₂ concentration,the concentration of O₂ is reduced and the sauce beef preservation effect gradually strengthen,of which 5%O₂/70%CO₂/25%N2 and 80%CO₂/20%N2 gas proportion have the two best effect in keeping sauce beef fresh.With the reduction of temperature,gas packaging of sauce beef can constantly improve the effect of the preservation,among which the storage of sauced beef under 10℃ temperature can extend the storage period of up to 30 days than under the 25℃ temperature.The storage under low temperature can be better able to extend the shelf life of sauce beef and keep its flavor.The differences of the effects of preservation of sauced beef under low temperature（10℃）vacuum control and room temperature（25℃）low oxygen and high carbon dioxide and oxygen free high carbon dioxide gas in a week are not significant.