低温等离子体处理对牛肉品质的影响

采用低温等离子体处理气调包装(modified atmospheric packaging，MAP)（O2: CO2: N2=35%: 35%: 30%）鲜牛肉，研究冷藏过程（4 ℃）中牛肉pH、色差、肌红蛋白、剪切力和质构变化，分析低温等离子体处理对冷藏过程中牛肉品质的影响。结果显示：在10 d冷藏过程中，经低温等离子体处理的牛肉pH值保持稳定，L*维持较高的亮度，始终高于未处理组；处理组牛肉的a*值呈先升高后降低的趋势，在第4 d达到最高值22.91，始终低于未处理组；b*值呈显著升高（p<0.05）10 d后高达14.43，且始终高于未处理组；处理组牛肉中的肌红蛋白总量呈减少趋势，而高铁肌红蛋白含量增加；10 d后，硬度、胶黏性和咀嚼性显著(p<0.05）下降4.78%、2.97%和6.13%，而弹性、内聚性和回复性的变化不明显。低温等离子体处理能够增强冷藏过程中牛肉表面亮度，降低红色，使肉色呈变黄趋势，对牛肉pH和质构特性无显著负面影响。
In order to study the effects of cold plasma treatments (modified atmospheric packaging (O2: CO2: N2=35%: 35%: 30%)) on sensory quality of beef, the pH, myoglobin, surface color, drip loss, shear force and texture changes of samples were analyzed during storage at 4 ℃ after cold plasma treatment. Results showed that during refrigerator storage, the pH of treated beef was relative stable, L* values were relative high, which were higher than that of untreated samples; a* values of treated samples were increased during 4 days then decreased, though they were lower than that of untreated samples; while the b* values were increased significantly (p<0.05) and higher than that of untreated beef; the total content of myoglobin were reduced, while the metmyoglobin amount was increased during the storage; the hardness, gumminess and chewiness significantly (p<0.05) decreased by 4.78%, 2.97% and 6.13%, respectively, while the elasticity, cohesiveness and recovery changed not significantly. These results indicated that the cold plasma treatment could enhance the brightness, reduce the redness, and increase the yellow color of beef surface, and it had no negative effects on the texture characteristics and pH of beef.