单宁和芦丁氧化前、后对河鲀鱼皮明胶特性的影响

Impacts of Tannin and Lutein before and after Oxidization on Gelatin Properties of Tiger Puffer(Takifugu rubripes)Skin Gelatin

为改善鱼皮明胶性能,通过添加不同比例的单宁、芦丁及其氧化态(0%,0.5%,1%,2%,4%),探究其对河鲀鱼皮明胶性质、颜色、水分分布、蛋白结构和蛋白条带的效应。结果表明,添加单宁、氧化单宁和芦丁,显著提高了河鲀鱼皮明胶强度、凝胶和融胶温度(P<0.05),而氧化芦丁的作用不显著。单宁酸、氧化单宁酸对河鲀鱼皮明胶的颜色影响不显著,而芦丁、氧化芦丁有显著影响,尤其是氧化芦丁,导致胶冻样品的L*值显著降低(6.07%~8.26%),提高了a*值(88.89%~93.88%)和b*值(85.94%~91.67%)。低场核磁共振结果显示,加入两种多酚及其氧化态,缩短了T2弛豫时间,促进了明胶与水分子的结合。冷场电镜显示,添加单宁、芦丁及其氧化态,有利于形成致密的凝胶网络结构。SDS-PAGE结果显示,明胶的蛋白条带无明显变化,多酚与明胶分子共价交联不显著,主要通过非共价方式相互作用。红外光谱显示,酰胺-A带和酰胺-I带均向蓝移,表明形成氢键数量增加。综合分析,单宁、芦丁及其氧化态可能通过非共价方式(氢键)与明胶分子结合,从而提高河鲀鱼皮明胶凝胶特性。本研究为提升河鲀鱼皮明胶性能贡献了一定依据。

In order to improve the properties of fish skin gelatin,different proportions of tannins,rutin and their oxidation states(0%,0.5%,1%,2%,4%)were added to investigate their impacts on the properties,color,water distribution,protein structure,and protein banding of puffer(Takifugu rubripes)skin gelatin.The results showed that the addition of tannin,oxidized tannin and rutin significantly increased the gelatin strength,gelling and melting temperature of the skin gelatin(P<0.05),while the effect of oxidized rutin was not obvious.Tannin and oxidized tannin demonstrate no significant effect on the gelatin color,while rutin and oxidized rutin have a significant effect,especially oxidized rutin,which results in a significant decrease in the L*value(6.07%-8.26%)of the gelatin,improvement of a*value(88.89%-93.88%)and b*value(85.94%-91.67%).Low-field nuclear magnetic resonance results showed that the addition of two polyphenols and their oxidation states shortened the T2relaxation time and promoted the combination of gelatin and water molecules.Cold field electron microscopy showed that addition of tannin,rutin and their oxidation states is beneficial to the formation of a dense gel network structure.SDS-PAGE results indicated that there was no obvious change in the protein bands of gelatin,and the covalent cross-linking between polyphenols and gelatin molecules was not significant,and they mainly interacted through non-covalent interactions.The infrared spectrum shows that both the amide-A band and the amide-I band shift to blue,indicating that the number of hydrogen bonds formed increases.Overall,tannin,rutin and their oxidation states may be combined with gelatin molecules through non-covalent interactions(especially hydrogen bonds),thereby improving the gel properties of puffer skin gelatin.These findings contribute certain evidences for property improvement of puffer skin gelatin.