热处理对扇贝闭壳肌肌动球蛋白生化性质的影响

Effect of Thermal Treatment on Biochemical Properties of Actomyosin from Adductor Muscles of Scallop

肌动球蛋白是扇贝闭壳肌中的主要功能蛋白质,对贝类制品的品质起关键的作用。文中以虾夷扇贝(Patinopecten yessoensis)闭壳肌为原料,提取其肌动球蛋白,并考察了热处理温度和时间对肌动球蛋白的α-螺旋含量、表面疏水性、活性-SH含量和浊度的影响。结果表明:在热处理过程中,扇贝闭壳肌肌动球蛋白的α-螺旋发生解旋,肽链展开,疏水性氨基酸残基暴露,蛋白表面疏水性增强;同时热处理使活性-SH氧化生成二硫键,蛋白聚集,使得扇贝闭壳肌肌动球蛋白的浊度增加。加热温度越高,这些指标变化越快。由此推断,扇贝闭壳肌肌动球蛋白在热处理过程中伴随着肽链的解旋和蛋白的无规则聚集。

Actomyosins are the main functional proteins of scallop adductor muscle proteins and they play a key role in the quality of shellfish products. Actomyosins were extracted from the adductor muscle of scallop （Patinopecten yessoensis）. Effects of heating temperature and time on the α-helix content, surface hydrophobicity, reactive sulfhydryl content and turbidity of scallop actomyosins were investigated. The experiment results showed that in the heating process the α-helix and peptide chains unfolded, residues of hydrophobic amino acid exposed, surface hydrophobicity of protein enhanced. At the same time, heat treatment converted reactive sulfhydryl into disulfide key, proteins gath- ered together, and the turbidity increased. The changes in these parameters accelerated as heating temperature in- creased. A conclusion can be induced that the thermal denaturation process of scallop adductor muscle actomyosins was accompanied with peptide chains despiralization and random aggregation.