不同气调包装结合冰温贮藏对羊肉保鲜效果的影响

Effect of Modified Atmosphere Packaging in Combination with Ice-Temperature on Quality of Mutton during Storage

为延长鲜羊肉的保鲜时间,研究不同气体组分的气调包装对羊肉冰温贮藏过程中品质的影响。以真空包装为对照,比较75%O2+25%CO2、75%N2+25%CO2气调包装羊肉在-1℃冰温条件下贮藏过程中感官品质、色泽、汁液流失率、嫩度、挥发性盐基氮、p H值、微生物等品质指标的变化。结果表明:真空包装羊肉的汁液流失率显著高于2种气调包装,而75%N2+25%CO2气调包装羊肉的色泽和感官评分最差。75%O2+25%CO2气调包装的保鲜效果最好,其色泽和感官评分最高,汁液流失率较小,p H值最低,-1℃冰温条件下贮藏42 d时,羊肉的菌落总数、假单胞菌菌数、乳酸菌菌数的对数值分别为5.91、5.95、5.23(lg(CFU/g)),其中菌落总数指标符合国家二级鲜肉标准。因此,-1℃冰温条件下结合75%O2+25%CO2气调包装可以使羊肉有效保鲜42 d,是较好的鲜羊肉保鲜方法。

In order to extend the storage life of fresh mutton, the effect of modified atmosphere packaging（MAP） with various gas components on the quality of fresh mutton during ice temperature storage was determined. Sensory evaluation scores, color, drip loss rate, total volatile nitrogen（TVB-N）, pH value and microbial loads of mutton samples packaged in 75% O2 ＋ 25% CO2 and 75% N2 ＋ 25% CO2 atmospheres and stored at ice temperature（-1 ℃） were analyzed. Vacuum packaging was used as control. The results showed that the drip loss rate of fresh mutton in vacuum package was significantly higher than that of modified atmosphere packaged mutton, but the color and sensory evaluation of mutton packaged in 75% N2 ＋ 25% CO2 atmosphere were worst among the three types of packages. Mutton packaged in 75% O2 ＋ 25% CO2 atmosphere had the best color and sensory evaluation scores, lower drip loss rate, and lower pH value. After 42 d storage of the mutton packaged in 75% O2 ＋ 25% CO2 atmosphere at ice temperature, the counts of total bacteria, Pseudomonas and lactic acid bacteria were 5.91, 5.95 and 5.23（lg（CFU/g））, respectively, and the total number of bacteria was not higher than that of first-grade fresh meat according to the national standard of China. In general, 75% O2 ＋ 25%CO2atmosphere package combined with ice temperature（-1 ℃） can extend the storage life of fresh mutton for as long as 42 days, and this method is suitable for maintaining the quality of fresh mutton during storage.