包装方式对宰后牛肉成熟过程中食用品质的影响

Effects of different packaging methods on beef quality during the postmortem aging

以真空包装作为对照,研究托盘包装和气调包装对牛肉宰后成熟过程中食用品质的影响。取6头宰后24h的黄牛左侧背最长肌,切割成大小基本相同的肉块并随机分组进行托盘包装、真空包装和气调包装(2.54cm厚),在4℃下冷藏成熟0,4,7,10d,分别测定颜色、嫩度、贮藏损失、离心损失、蒸煮损失和水分分布状态,评价包装方式对宰后成熟过程中牛肉食用品质的影响。结果表明:与真空包装相比,托盘包装和气调包装牛肉样品的蒸煮损失在宰后成熟过程中无显著性差异(P>0.05),而贮藏损失差异显著(P<0.05);托盘包装和气调包装牛肉样品的a*值和自由水含量较高(P<0.05),而托盘包装和气调包装牛肉样品的嫩度显著低于对照组(P<0.05)。说明气调包装和托盘包装有助于改善牛肉的颜色,而对牛肉嫩度和水分分布状态却不具有改善作用。

Effects of air packaging and modified atmosphere packaging on the quality of fresh beef during postmortem aging was studied u- sing vacuum packaging as control treatment. Six left side of Zongissi mus dorsi muscles of yellow cattle were precooled at 4 ℃ for 24 h. After 24 h postmortem, beef samples （2.54 cm thick） were trimmed and mixed, and randomly divided into three groups. The beefsamples were stored for 4 d, 7 d and 10 d in dark refrigeration house at 4 ℃ to mimic commercial storage conditions. At the end of each point, the meat color, tenderness, purge loss, centrifuge loss, cook- ing loss and the state of moisture distribution were determined imme- diately to evaluate the effect of different packaging methods on beef quality during postmortem aging. The results showed that the cooking loss of samples from air packaging and modified atmosphere packaging was not different significantly compared to vacuum paeka ging （P〈0.05）, while the purge loss of samples from air packaging and modified atmosphere packaging was significantly different （P〈 0.05）. Air packaging and modified atmosphere packaging presented better improvement on CIE a ＊ values and higher population of free water and lower tenderness compared to vacuum packaging （P 〈0.05）. In conclusion, air packaging and modified atmosphere packa- ging could improve the color of beef samples compared to vacuum packaging. However, air packaging and modified atmosphere packa ging could not improve the tenderness and the state of moisture dis tribution.