冰温结合不同比例氧气气调对冷却肉的保鲜效果

试验研究了在冰温基础上结合不同含氧比例气调对冷却猪肉保鲜的影响，试验设置冰温、冷藏（4℃）、真空包装+冰温、20%CO2+80%O2（高氧）+冰温、20%CO2+20%O2+60%N2（低氧）+冰温、20%CO2+80%N2（无氧）+冰温6个试验组，测定菌落总数、挥发性盐基氮、汁液流失率、保水能力和色差。结果表明：冰温条件下高氧和低氧的菌落总数24 d还未超过冷却肉卫生标准，且两组之间无显著差异（P＞0.05）；在整个贮藏期内高氧气调和低氧气调可以维持冷却肉的色泽在一个小的范围内变化；高氧气调和低氧气调8 d后汁液流失率显著高于单纯冰温和无氧气调（P＜0.05），高氧气调12 d后汁液流失率显著高于低氧气调（P＜0.05），同时高氧气调8 d后持水能力显著大于低氧气调（P＜0.05）。在冰温条件下，80%O2和20%O2都能长时间维护冷却肉的色泽，均能较好抑制微生物的增殖，但在汁液流失率、保水能力方面各有优势。

Effect of modified atmosphere package with varying oxygen concentrations combined with controlled freezing-point storage on pork fresh-keeping

Effect of modified atmosphere packaging with varying oxygen concentrations combined controlled freezing-point storage on pork fresh-keeping was studied. By determining physicochemical parameters such as total plate count, total volatile base nitrogen (TVB-N), drip loss, water holding capacity and color, the qualities of pork under controlled freezing-point storage, chill storage, vacuum package+controlled freezing-point storage, 20%CO_2+80%O_2 (high oxygen)+controlled freezing-point storage, 20%CO_2+20%O_2+60%N_2 (low oxygen)+controlled freezing-point storage and 20%CO_2+80%N_2(no oxygen)+controlled freezing-point storage were compared. It showed that total plate count under high oxygen and low oxygen did not exceed the hygiene standard of pork after twenty-four days, and there was no significant difference between them(P>0.05). High oxygen modified atmosphere package(MAP) and low oxygen MAP maintained the color better. The drip losses of high oxygen MAP and low oxygen MAP after eight days were significantly higher than that of controlled freezing-point storage (P<0.05) and no oxygen MAP, and the drip loss of high oxygen MAP was significantly higher than that of low oxygen MAP after twelve days (P<0.05), in addition, the water holding capacity of high oxygen MAP was significantly higher than that of low oxygen MAP after eight days (P< 0.05). Both high oxygen MAP and low oxygen MAP combined controlled freezing-point storage could maintain the favorable color long time and inhibit microorganism reproduce, however, each of them has advantages either in drip loss water or holding capacity.