酸/碱预处理对美洲鳗鲡（Anguilla rostrata）鱼骨明胶理化性质与凝胶特性的影响

以美洲鳗鲡（Anguilla rostrata）鱼骨为原料，采用酸或碱预处理结合热水浸提制备鱼骨明胶，并通过得率、凝胶强度测定、SDS-PAGE、紫外全波长扫描、红外光谱扫描、动态流变学测定以及扫描电镜等研究鱼骨明胶的理化性质和凝胶特性。结果表明:酸法预处理明胶（AG60）与碱法预处理明胶（BG60）得率分别为13.6%和6.88%，凝胶强度分别为101.95 g和78.74 g。AG60和BG60的羟脯氨酸含量为3.2 g/100 g和2.7 g/100 g。两种明胶均含有β和α₁、α₂链，其中AG60的α₁+α₂含量显著高于BG60。AG60与BG60均具有明胶的特征吸收峰，且无杂蛋白吸收峰。与BG60相比，AG60具有更高的凝胶温度与熔融温度，以及更短的胶凝时间。扫描电镜分析显示，AG60具有更致密、均一的凝胶网络结构。本研究表明，与碱法预处理相比，酸法预处理制备得到的鳗鱼骨明胶具有更高的得率与更好的凝胶特性。

Effects of Acidic/Alkali Pretreatment on Physicochemical Properties and Gelation Characteristics of Bone Gelatin from American Eel (Anguilla rostrata)

Fish bone gelatins were prepared from Anguilla rostrata by acidic or alkali pretreatment combined with hot water extraction. The physicochemical properties and gel properties of fish bone gelatins were investigated via the yield determination, gel strength measurement, SDS-PAGE analysis, ultraviolet full-wavelength scanning, infrared spectrum scanning, dynamic rheology measurement and scanning electron microscopy. As results, the yields of acid pretreated gelatin (AG60) and alkaline pretreated gelatin (BG60) were 13.6% and 6.88%, with the corresponding gel strengths of 101.95 g and 78.74 g, respectively. The hydroxyproline contents of AG60 and BG60 were 3.2 g/100 g and 2.7 g/100 g. Both gelatins were mainly consisted of β and α₁, α₂ chains, the contents of α₁ and α₂ chains in AG60 was significantly higher than those in BG60. Both AG60 and BG60 possessed the characteristic absorption peak of gelatin without any absorption peaks for other proteins. The AG60 possessed higher gelling temperature and melting temperature, as well as a shorter gelling time. Scanning electron microscopy analysis showed that AG60 showed a more dense and uniform gel network structure as compared with BG60. Present study suggested that the eel bone gelatin prepared by acidic pretreatment had better gel properties than that of gelatin prepared by alkali pretreatment.