食品科学 ›› 2008, Vol. 29 ›› Issue (4): 149-153.

• 基础研究 • 上一篇    下一篇

兔肌球蛋白热诱导凝胶过程中的物理化学变化

 曾宪明, 徐幸莲, 白云, 周光宏   

  1. 南京农业大学教育部肉制品加工与质量控制重点实验室; 南京农业大学教育部肉制品加工与质量控制重点实验室
  • 出版日期:2008-04-15 发布日期:2011-08-24

Physico-chemical Changes during Heat-induced Gelation of Rabbit Skeletal Myosin

 ZENG  Xian-Ming, XU  Xing-Lian, BAI  Yun, ZHOU  Guang-Hong   

  1. Key Laboratory of Meat Processing and Quality Control, Ministry of Education, Nanjing Agricultural University
  • Online:2008-04-15 Published:2011-08-24

摘要: 研究在pH6.5、高离子强度(0.6mol/LKCl)下兔肌球蛋白热诱导凝胶过程中的物理化学特性的变化。α-螺旋含量从25℃开始缓慢减小,43℃后开始急剧减小,直到65℃左右后基本不发生变化;浊度从40℃左右开始增加,表明了凝集的开始,至65℃后不再变化。活性巯基含量40℃开始增加,65℃达到最大值;总巯基含量从30℃开始降低;疏水性在30~85℃间呈非线性增加趋势;G’(贮能模量)从48℃开始增加,在48~71℃间缓慢增加,71~82℃间急剧增加。表明肌球蛋白热变性从α-螺旋的解折叠开始,进而促进疏水基团和巯基基团的暴露;二硫键与疏水作用、分子间氢键等共同作用促进凝胶强度的增加。

关键词: 肌球蛋白, 凝胶, 物化特性

Abstract: The mechanism of heat-induced gelation of myosin was investigated by studying physico-chemical changes of rabbit myosin during at pH 6.5, high ionic strength of 0.6mol/L KCl. A slight decrease in α-helical content was observed at 25 ℃, then a rapid decrease from 43 to 65 ℃, followed by a plateau after 65 ℃. Turbidity increased at 40 ℃ which indicated the beginning of the aggregation, remaining constantly after 65 ℃. Reactive sulfhydryl content increased from 40 ℃, reaching a maximum at 65 ℃. Total sulphydryl content decreased from 30 ℃. Surface hydrophobicity increased non-linearly between 30~85 ℃. G’ increased slowly between 48 and 71 ℃, sharply from 71 to 82 ℃. It was concluded that denaturation of myosin was initialized by unfolding of the α-helical and followed by the exposure of sulphydryl and hydrophobic residues. Disulfide linkages, hydrophobic interactions and hydrogen bonds could enhance the elasticity of the gelation of myosin together.

Key words: myosin, gelation, physico-chemical characteristics