Fan Hui Yin, Dumont Marie-Josée, Simpson Benjamin K
Faculty of Food Science and Nutrition, Universiti Malaysia Sabah, 88400, Kota Kinabalu, Sabah, Malaysia.
Department of Bioresource Engineering, McGill University (Macdonald Campus), 21,111 Lakeshore Rd, Ste. Anne de Bellevue, QC, H9X 3V9, Canada.
Curr Res Food Sci. 2020 Apr 17;3:146-157. doi: 10.1016/j.crfs.2020.04.002. eCollection 2020 Nov.
The recovery of gelatins from Atlantic salmon () skin for film formation and characterization was studied. Fish skins pre-treated with trypsin (250 U/g) produced the highest hydroxyproline content (7.41 ± 0.49 mg hydroxyproline/g treated skin) and yield (53.05 ± 4.38%) of gelatin, as compared to the use of saline solution. Pre-treatment with a lower concentration of trypsin (1 U/g) at a shorter pre-treatment time successfully reduced the degradation of gelatin with co-production of high molecular weight -chains. Gelatin was further extracted by a trypsin-aided process for film formation and characterization. Films with increasing protein concentration (from 1 to 5%, w/v) exhibited higher thickness, tensile strength, and elongation at break (EAB), but a marked decrease in EAB for films with 6 and 7% (w/v). Films with 5% proteins showed higher thickness, lower tensile strength and higher EAB with increasing concentrations of glycerol (from 10 to 50% of proteins, w/w). All films exhibited high water uptake, decrease in light transmission and an increase in opacity as the protein and glycerol contents increased. Electrophoretic studies showed that the increase in the mechanical properties of the films was correlated with the increase in protein concentration, owing to the increased content of high molecular weight chain fractions. Furthermore, Fourier transform infrared spectroscopy (FTIR) and scanning electron microscopy (SEM) revealed the interaction between the proteins and glycerol for all films. This study demonstrated the viability of the trypsin supplementation process to obtain salmon skin gelatin for film formation.
研究了从大西洋鲑鱼（）皮中提取明胶用于成膜及表征的方法。与使用盐溶液相比，用胰蛋白酶（250 U/g）预处理的鱼皮产生的明胶羟脯氨酸含量最高（7.41±0.49 mg羟脯氨酸/g处理后的皮肤），产率也最高（53.05±4.38%）。在较短预处理时间下用较低浓度的胰蛋白酶（1 U/g）预处理成功减少了明胶的降解，并共同产生了高分子量的α-链。通过胰蛋白酶辅助工艺进一步提取明胶用于成膜及表征。随着蛋白质浓度（从1%到5%，w/v）增加，薄膜表现出更高的厚度、拉伸强度和断裂伸长率（EAB），但对于蛋白质含量为6%和7%（w/v）的薄膜，EAB显著降低。含5%蛋白质的薄膜随着甘油浓度增加（从蛋白质的10%到50%，w/w）表现出更高的厚度、更低的拉伸强度和更高的EAB。随着蛋白质和甘油含量增加，所有薄膜均表现出高吸水率、透光率降低和不透明度增加。电泳研究表明，由于高分子量链级分含量增加，薄膜机械性能的提高与蛋白质浓度增加相关。此外，傅里叶变换红外光谱（FTIR）和扫描电子显微镜（SEM）揭示了所有薄膜中蛋白质与甘油之间的相互作用。本研究证明了补充胰蛋白酶工艺用于制备用于成膜的鲑鱼皮明胶的可行性。
