Shi Linfan, Tian Haohao, Wang Yanxia, Hao Gengxin, Chen Jun, Weng Wuyin
College of Food and Biological Engineering, Jimei University, Xiamen, China.
Engineering Research Center of the Modern Technology for Eel Industry, Ministry of Education, Xiamen, China.
J Sci Food Agric. 2020 Oct;100(13):4801-4807. doi: 10.1002/jsfa.10539. Epub 2020 Jun 22.
Application of fish skin collagen has received increasing attention due to mammalian derived diseases and religious limitations. Collagen fibril gel could be formed in vitro through the self-assembly process. The present study investigated the effect of pH on the self-assembly in vitro of acid-solubilized collagen (ASC) from golden pompano skin by determining the turbidity, rheological viscoelasticity, network structure, gel strength, and thermal stability of collagen fibril gel.
The isoelectric point of ASC was pH 5.27. The turbidity-time and rheological viscoelasticity results indicate that the collagen self-assembly rate in vitro at pH 7.0 was the slowest. The rate was accelerated by increasing or decreasing the pH. Scanning electron microscopy images show that the fibril diameters of the collagen fibril gels and the collagenous fibril number in the collagen fiber increased with the pH. The gel strength of the collagen fibril gel prepared at pH 5.0 was 22.06 g and increased up to 220.46 g when pH increased to 8.0. No obvious peaks were observed in the differential scanning calorimetry curves of the collagen fibril gels prepared at pH 5.0, whereas high endothermic peak temperature (T ) and enthalpy change (ΔH) were found in the collagen fibril gels prepared at pH 6.0-8.0.
It is concluded that the physical properties of ASC fibril gels can be improved by increasing the fibril diameter controlled by pH. © 2020 Society of Chemical Industry.
由于哺乳动物源性疾病和宗教限制，鱼皮胶原蛋白的应用受到越来越多的关注。胶原纤维凝胶可通过体外自组装过程形成。本研究通过测定胶原纤维凝胶的浊度、流变粘弹性、网络结构、凝胶强度和热稳定性，研究了pH对金鲳鱼皮酸溶性胶原蛋白（ASC）体外自组装的影响。
ASC的等电点为pH 5.27。浊度-时间和流变粘弹性结果表明，pH 7.0时胶原蛋白体外自组装速率最慢。通过升高或降低pH可加速该速率。扫描电子显微镜图像显示，胶原纤维凝胶的纤维直径和胶原纤维中的胶原纤维数量随pH升高而增加。pH 5.0制备的胶原纤维凝胶的凝胶强度为22.06 g，当pH升高到8.0时增加到220.46 g。pH 5.0制备的胶原纤维凝胶的差示扫描量热曲线中未观察到明显峰，而在pH 6.0 - 8.0制备的胶原纤维凝胶中发现了较高的吸热峰温度（T）和焓变（ΔH）。
得出结论，通过增加由pH控制的纤维直径可改善ASC纤维凝胶的物理性质。© 2020化学工业协会。
