不同类型电场辅助冰温贮藏对生鲜猪肉保水性的影响

为研究不同类型电场辅助冰温贮藏对生鲜猪肉保水性的影响，以猪背最长肌为研究对象，对比分析在交变电场辅助冰温、静电场辅助冰温及普通冰温（对照组）贮藏条件下生鲜猪肉水分含量、贮藏损失、蒸煮损失、横向弛豫时间T2、肌原纤维蛋白表面疏水性及结构的变化。结果表明：交变电场和静电场处理组生鲜猪肉水分含量和不易流动水弛豫峰面积比例P21显著高于对照组（P＜0.05），贮藏损失、蒸煮损失、肌原纤维蛋白表面疏水性及自由水弛豫峰面积比例P22显著低于对照组（P＜0.05），但交变电场处理组和静电场处理组各指标之间无显著差异。综上，输出电压为3 300～4 000 V所产生的交变电场和输出电压为3 800 V所产生的静电场辅助冰温贮藏均可延缓肌原纤维蛋白降解及不易流动水向自由水转化，从而提高生鲜猪肉的保水性，降低贮藏过程中的汁液损失。

Effects of Different Types of Electric Field Combined with Controlled Freezing-Point Storage on Water Retention Properties of Fresh Pork

In order to study the effects of different types of electric field combined with controlled freezing-point storage on the water retention properties of fresh pork, the changes in the moisture content, storage loss, cooking loss, transverse relaxation time T2, surface hydrophobicity and structure of myofibrillar protein in pork Longissimus dorsi were comparatively analyzed under different storage conditions, namely alternating electric field-assisted controlled freezing-point storage (?1.0 ± 0.5) ℃, electrostatic field-assisted controlled freezing-point storage and controlled freezing-point storage (control group). The results showed that the moisture content and relaxation peak area percentage (P21) for immobile water in the alternating electric field and electrostatic field treatment groups were significantly higher than those in the control group (P < 0.05), and the storage loss, cooking loss, surface hydrophobicity of myofibrillar protein and relaxation peak area percentage (P22) for free water were significantly lower than those in the control group (P < 0.05), but there was no significant difference between the electrostatic field treatment groups. In conclusion, both electrostatic fields can delay the degradation of myofibrillar protein and the transformation of immobile water into free water, consequently improving the water retention properties and reduce the juice loss of fresh pork during storage.