不同冻结储藏方式对河蟹感官品质的影响

Effects of different freezing methods on the sensory quality of crab muscles

目的研究不同冻结速率和保水剂处理对冻藏河蟹感官品质的影响,为河蟹加工产业的原料保存提供技术参考。方法采用冰柜慢冻(慢冻组)、风冷速冻(速冻组)、食盐水保水剂浸渍及风冷速冻(保水剂+速冻组)分别对河蟹进行冻结处理,以傅里叶变换红外光谱分析3组处理河蟹样品和新鲜河蟹肌肉蛋白质中的二级结构含量,通过质构仪测定河蟹不同部位肌肉组织的弹性、硬度和咀嚼性,扫描电镜观察肌肉组织微观结构,电子鼻技术分析风味,以及感官评定综合评价不同处理河蟹的感官品质。结果保水剂+速冻可以显著延缓冻藏河蟹品质的不良变化,蛋白质中α-螺旋结构含量相对慢冻或直接速冻处理较高,质构、肌肉纤维微结构、风味和口感都更接近新鲜河蟹。结论食盐作为安全的保水剂,结合速冻方式,有助于保持冻藏河蟹的肌肉品质,且风味无不良影响。

Objective To investigate the effects of different freezing rates and water-holding agents on the sensory quality of frozen crabs, and provide technical references for the material storage in crab processing industry. Methods Slow freezers frozen（slow freezing group）, air-cooled quick-freezing（rapid freezing group）, salt water protection agent impregnating and air-cooled quick-freezing（water-holding agent＋rapid freezing group） were used to freeze crabs. Fourier transform infrared spectroscopy（FTIR） was used to analyze the secondary structure in the muscle protein of crab samples and fresh crabs. The elasticity, hardness and mastication of muscle tissue in different parts of the crab were determined by means of plasticity apparatus. The microstructure of muscle tissue was observed by scanning electron microscope（SEM）. The flavor was analyzed by electronic nose. And the sensory quality of the crab was comprehensively evaluated by sensory evaluation. Results The water-holding agent＋rapid freezing group could significantly delay the bad quality of the frozen river crab, and the content of α-helical structure in protein was higher than that of slow freezing or direct freezing. Texture, muscle fiber microstructure, flavor and taste of water-holding agent＋rapid freezing group were all closer to fresh crabs. Conclusion Salt as a safe water-holding agent, combined with rapid freezing, can helps to maintain the muscle quality of the frozen river crab, and the flavor has no adverse effects.