College of Food Science, Southwest University, Chongqing 400716, China.
College of Food Science, Southwest University, Chongqing 400716, China.
Int J Biol Macromol. 2018 Oct 15;118(Pt A):435-441. doi: 10.1016/j.ijbiomac.2018.06.106. Epub 2018 Jun 27.
The method of liquid nitrogen quick-freezing combined with dilute acid rapid-thawing was applied as a pretreatment to extract gelatins from pigskins, and the influence of HCl concentration (0-2% (v/v)) on the gelatinization of collagen in pigskins was observed. The freezing-thawing using liquid nitrogen and water did not effectively induce the gelatinization of collagen, and the replacement of water with dilute HCl solutions improved this situation. The gelatin pretreated with liquid nitrogen and 1% HCl showed the highest yield and strongest gel properties, since the hydrogen bonds balance and the triple-helical structure in collagen were damaged moderately after this pretreatment to promote the release of subunit components in collagen during gelatin extraction. The surface of the gelatinized collagen via freezing-thawing pretreatment with liquid nitrogen and 1% HCl showed a similar honeycomb shape as traditional acid pretreatment. However, the pretreatment time could be shortened from 6 h (traditional acid method) to 20 min. Therefore, the freezing-thawing method combined with liquid nitrogen and dilute acid could be potentially used in gelatin preparation.
采用液氮快速冷冻结合稀酸快速解冻的方法作为预处理，从猪皮中提取明胶，并观察 HCl 浓度（0-2%（v/v））对猪皮中胶原蛋白的胶凝作用的影响。使用液氮和水的冷冻-解冻并不能有效地诱导胶原蛋白的胶凝，而用稀 HCl 溶液代替水则改善了这种情况。用液氮和 1%HCl 预处理的明胶的产率最高，凝胶性能最强，因为这种预处理适度破坏了胶原蛋白中的氢键平衡和三螺旋结构，从而促进胶原蛋白提取过程中亚单位成分的释放。通过液氮和 1%HCl 的冷冻-解冻预处理使胶原蛋白胶凝，其表面呈现出类似于传统酸预处理的蜂窝状形状。然而，预处理时间可以从 6 小时（传统酸法）缩短至 20 分钟。因此，液氮和稀酸相结合的冷冻-解冻方法可能可用于明胶的制备。
