涂膜处理对贮藏过程中冷却猪肉品质变化的影响

Effect of Coating on Quality Change of Chilled Pork during Storage

探索涂膜处理对贮藏过程中冷却猪肉品质变化的影响。测定温度对茶多酚抑菌性能的影响,将冷却猪肉先经H2O2处理,使其成为无菌肉模型,并对其接种单一菌假单胞菌,再进行涂膜处理(海藻酸钠涂膜组、海藻酸钠-茶多酚涂膜组、壳聚糖涂膜组、壳聚糖-茶多酚涂膜组),然后4℃条件下贮藏21d,每隔3d取样,进行pH值、TVB-N值、TBARs值、假单胞菌菌落数、电泳图谱、感官评定的测定,并对不同贮藏期样品的各项指标进行对比。结果表明:涂膜组保鲜效果均优于对照组,其中以壳聚糖-茶多酚涂膜组保鲜效果最好,其pH值、TVB-N值、TBARs值、假单胞菌菌落数均最低,电泳图谱颜色深且条带宽,感官评分最高;贮存21d时,该组冷却猪肉仍为1级鲜度。因此,涂膜处理可有效延长冷却猪肉的货架期。

Our present work aimed to explore the effect of coating on quality change of chilled pork during storage. We investigated the effect of temperature on the antimicrobial properties of tea polyphenols. Chilled pork was sterilized with H202 to establish an aseptic meat model. The model was inoculated with a single strain of Pseudomonas and then subjected to treatment with different coatings （sodium alginate coating, sodium alginate/tea polyphenol coating, chitosan coating and chitosan-tea polyphenol coating）. The coated samples were stored at 4 ℃ for 21 days. The pH, TVB-N, TBARs, Pseudomonas colony counts, electrophoresis pattern and sensory score were determined every 3 days during the storage period. The results obtained were compared among four coating treatment groups. All the coating treatments could effectively preserve chilled pork compared to the control group, and the chitosan-tea polyphenol coating displayed the lowest values of pH, TVB-N, TBARs and the number of Pseudomonas colonies, darker and wider electrophoresis bands and the highest sensory evaluation score. After 21 d of storage, the meats from the group remained fresh at grade 1. Therefore, the shelf life of chilled pork could be effectively extended by pre-coating during storage.