蓄冷材料对风冷冰箱中猪肉品质的影响

通过在风冷冰箱冷冻室中配置蓄冷材料，分别测定了实验组（添加蓄冷材料）和对照组（未添加蓄冷材料）冷冻室中温度的变化和冷冻肉块的干耗率、解冻汁液流失率、色差、质构、剪切力、微观结构、孔隙率等指标，分析了蓄冷材料对冷冻肉品质的影响。结果显示，相比对照组，实验组风冷冰箱冷冻室内温度波动明显减小（±0.36 ℃），通过最大冰晶生长带的时间缩短61 min，冻存肉块的干耗率、解冻汁液流失率明显减小，咀嚼性更优；肌间冰晶重结晶减弱，冰晶分布均匀，对肉块内部的机械损伤减弱，肌纤维的完整性得以更好的保持。结果证明，蓄冷材料对维持冷冻肉的品质具有可行性，为更好地优化风冷冰箱性能提供了依据。

Effects of Phase Change Material on the Quality of Frozen Pork in Frost-Free Refrigerator

In this study, phase change material was placed in the freezing chamber of a frost-free refrigerator to examine its effect on the quality of frozen pork. The changes in freezing chamber temperature in the experimental group (with phase change material) and the control group (without phase change material) were recorded. Weight loss rate, dripping loss rate, color difference, texture, Warner-Bratzler shear force (WBSF) values, microstructure, and porosity of frozen pork were used to evaluate the effectiveness of phase change material. The results showed that the temperature fluctuation was significantly smaller (± 0.36 ℃) in the experimental group compared with the control group. The time required to pass through the maximum ice crystal growth zone was reduced by 61 min. Compared with the control group, weight loss rate and dripping loss rate of frozen pork were decreased significantly in the experimental group. Microscopic and micro-CT image results showed that ice crystals were distributed uniformly and the ice recrystallization between muscle fibers was reduced. These results indicated that the mechanical damage of the inner tissue was reduced and the integrity of the muscle fiber was maintained. The results of this research have proved that phase change material is feasible to maintain the quality of frozen pork and provided a potential way to improve the performance of frost-free refrigerator.