高氧气调包装对不同品种冷却猪肉贮藏品质及持水性的影响

Influence of high oxygen modified atmosphere packaging on different breeds of chilled pork meat quality and water holding capacity during storage

为了研究不同品种冷却猪肉在高氧气调包装贮藏过程中,蛋白氧化对猪肉品质及持水性的影响,试验以氟烷基因（NN）型杜长大三元杂交猪和不含NN基因型的三门峡黑猪为研究对象,分析了2个品种猪肉经高氧气调包装（80%O2＋20%CO2）,于（4±1）℃下贮藏过程中肌肉色泽、蛋白质氧化、水分分布、保水性以及肌肉微观结构的变化。结果表明,随着贮藏时间的延长（0-10 d）,2个品种猪肉的肌原纤维蛋白羰基含量显著升高（P〈0.05）,巯基含量显著降低（P〈0.05）,表明猪肉肌原纤维蛋白的氧化程度随着贮藏时间的延长而加剧;肌原纤维蛋白发生持续性氧化,肌原纤维蛋白骨架的完整性遭到不同程度破坏,肌束膜破裂,纤维束间隙增大,结构疏松,保水性降低,不易流动水逐渐态变为自由水;与贮藏初始相比,第3天时杜长大三元杂交猪和三门峡黑猪的不易流动水均显著降低（P〈0.05）,第5天杜长大三元杂交猪的自由水显著增加（P〈0.05）,而黑猪的自由水在第10天时显著性增加（P〈0.05）;贮藏5 d以上时,2个品种猪肉的蒸煮损失率均较对照组的蒸煮损失显著增大（P〈0.05）;2个品种猪肉的L＊值、a＊值、b＊值均呈现先增加再降低的趋势,L＊值在第7天时达到最大值,a＊值在第3天时达到最大值,杜长大三元杂交猪和黑猪的b＊值分别在第5天和第7天时达到最大值;2个品种的猪肉经高氧气调包装,其色泽、蛋白质氧化、水分态变、保水性、微观结构等指标变化规律相似,表明高氧气调包装对2种猪肉的贮藏品质及持水性的影响效应具有一致性。研究结果为高氧气调包装冷却猪肉贮藏品质及汁液流失控制提供依据。

Pork is one of the most commonly consumed meat worldwide, and its quality has received great attention. Pork quality is evaluated by edible quality, nutritional quality, health and safety quality and technical quality, and consumers often rate meat by their nutritional quality and edible quality, which are mainly determined by protein content, meat tenderness and water retention. Meat tenderness has a good linear correlation with cooking loss. Since the chilled meat is susceptible to contamination during the process of storage and circulation, ensuring the quality of chilled meat and meanwhile extending the storage period have great significance for the development of chilled meat. High oxygen modified atmosphere is a new packaging technique, which usually contains 70%-80% oxygen and 20%-30% carbon dioxide and can effectively extend the shelf life of meat. Oxygen can ensure the stabilization of meats＇ red color and carbon dioxide will prolong the shelf life of meats by inhibiting the microorganism growth. Meat in the high oxygen modified atmosphere packaging will produce a series of complex physical and chemical and biochemical changes, and these changes have important influence on the quality. The investigate the protein oxidation effect on pork quality and water holding capacity when the different varieties chilled pork were stored in high oxygen modified atmosphere packaging. Crossbred pigs（Duroc × Landrace × Yorkshire）（with halothane genotype NN） and Sanmenxia black pigs（without halothane NN gene） were used in this experiment. The changes of CIE＊ color（L＊, a＊, b＊）, protein oxidation, water distribution, water holding capacity and muscle microstructure during the storage at 4℃ in high oxygen modified atmosphere packaging（80% O2 ＋ 20% CO2） were determined. The results showed that with the extension of storage time（0-10 day）, carbonyl content increased significantly（P〈0.05） and sulfhydryl content declined significantly（P〈0.05）. The results also showed that myofibril protein oxidation from the 2 types of pigs became more severe with the extension of storage time, which induced the breakdown of the structure of myofibrils. The microstructure of the myofibrils was altered obviously, which was indicated by perimysium rupture, increasing of space between fibers, and loose structure. It was observed that immobilized water converted to free water and thus water holding capacity decreased. Immobilized water of both the crossbred pigs and the black pigs declined significantly（P〈0.05） at the 3rd day compared with the control. Compared with that of the control（at the initial state）, free water in the meat of the crossbred pigs and the black pigs on the 3rd day decreased, while it increased significantly（P〈0.05） on the 5th day for the crossbred pigs and on the 10 th day for the black pigs, respectively. Cooking losses of the meat from 2 breeds of pigs increased significantly compared with that of control（P〈0.05） when the storage time was longer than 5 d. Meanwhile, CIE＊ colors of the 2 breeds of pigs were increased at first and then decreased. The L＊ values of meat from the 2 breeds of pigs reached the maximum on the 7th day. The a＊ values reached the maximum on the 3rd day. The b＊ values of meat from the crossbred pigs and black pigs reached the maximum value on the 5th and 7th day, respectively. Results show that high oxygen modified atmosphere packaging has the similar effects on CIE＊ color, protein oxidation, water state change, water holding capacity and microstructure of meat from the 2 breeds of pigs, which indicates that the effects of high oxygen modified atmosphere packaging on pork meat quality and water holding capacity are universal. The results provide the basis for control pork quality and cooking loss during cooling meat storaged in high oxygen modified atmosphere packaging.