The objective of this study was to evaluate the nutritional quality and physical characteristics of soluble proteins separated from silver carp at 4, 20, and 40 °C. Ground silver carp was diluted, and soluble proteins were separated by centrifugation and dried. The proximate composition (dry wt) of the protein powders averaged 82.42% protein, 3.25% lipid, and 14.50% ash. Average protein recovery yield was 11.78% with the better yields occurring at 20 °C (P < 0.05). Mineral profile revealed greater concentrations of Fe, Mg, P, and Na when compared to the initial homogenate. More saturated and monounsaturated fatty acids were recovered in the 4 °C powder and the least in the 40 °C powder (P < 0.05). Polyunsaturated fatty acids displayed a reverse trend, with the greatest concentration in the 40 °C powder and the least in the 4 °C powder (P < 0.05). The amino acid profile revealed that the protein powder met all FAO/WHO/UNO amino acid requirements for adults. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) revealed high amounts of low and medium molecular weight (MW) proteins (10-15 and 25-50 kDa, respectively). Two-dimensional (2-D) electrophoresis indicated that the low MW proteins possessed a neutral isoelectric point relative to that of the medium MW proteins. The protein powder was significantly less soluble (P < 0.05) than whey protein concentrate 80 at every pH tested (pH 3.0 to 11.0). Similar tendencies were seen when ionic strength was shifted (0.0 to 1.1 I; P < 0.05). Soluble protein powders derived from silver carp are nutrient rich and have physical characteristics resembling whey protein concentrate. Changes in process temperature had limited effects on protein powder composition. PRACTICAL APPLICATION Soluble proteins contribute to 20 to 40% of fish protein and are soluble in neutral salt solutions. Much of the sarcoplasmic proteins are lost when they solubilize in processing water and are discarded similarly to how whey protein was once discarded during dairy processing. When government regulations on whey disposal were implemented, the dairy industry responded by repurposing the high-quality protein for human use and it is now a billion dollar industry. The aim of this research project was to verify the composition of an otherwise overlooked protein source.

中文翻译：

---

鲢鱼可溶性蛋白质的营养品质和物理特性

本研究的目的是评估在 4、20 和 40 °C 下从鲢鱼中分离出的可溶性蛋白质的营养品质和物理特性。将磨碎的鲢鱼稀释，通过离心分离可溶性蛋白质并干燥。蛋白质粉末的近似组成（干重）平均为 82.42% 蛋白质、3.25% 脂质和 14.50% 灰分。平均蛋白质回收率为 11.78%，在 20 °C 时产率更高（P < 0.05）。与初始匀浆相比，矿物剖面显示铁、镁、磷和钠的浓度更高。4 ℃粉末中回收的饱和和单不饱和脂肪酸较多，40 ℃粉末中回收最少（P < 0.05）。多不饱和脂肪酸呈相反趋势，40℃粉末中浓度最高，4℃粉末中浓度最低（P < 0.05)。氨基酸谱显示，该蛋白粉符合粮农组织/世界卫生组织/UNO 对成人的所有氨基酸要求。十二烷基硫酸钠-聚丙烯酰胺凝胶电泳 (SDS-PAGE) 显示大量的低分子量和中等分子量 (MW) 蛋白质（分别为 10-15 和 25-50 kDa）。二维 (2-D) 电泳表明低分子量蛋白质相对于中等分子量蛋白质具有中性等电点。在每个测试的 pH 值（pH 3.0 至 11.0）下，蛋白粉的可溶性（P < 0.05）明显低于浓缩乳清蛋白 80。当离子强度发生变化时（0.0 至 1.1 I；P < 0.05），也出现了类似的趋势。来自鲢鱼的可溶性蛋白粉营养丰富，具有类似于浓缩乳清蛋白的物理特性。工艺温度的变化对蛋白粉成分的影响有限。实际应用 可溶性蛋白质占鱼蛋白的 20% 至 40%，可溶于中性盐溶液。大部分肌浆蛋白在溶解于加工水中时会丢失，并且与乳清蛋白在乳制品加工过程中的丢弃方式类似。当政府实施有关乳清处理的法规时，乳制品行业的反应是重新利用优质蛋白质供人类使用，现在它是一个价值十亿美元的行业。该研究项目的目的是验证一种原本被忽视的蛋白质来源的组成。大部分肌浆蛋白在溶解于加工水中时会丢失，并且与乳清蛋白在乳制品加工过程中的丢弃方式类似。当政府实施有关乳清处理的法规时，乳制品行业的反应是重新利用优质蛋白质供人类使用，现在它是一个价值十亿美元的行业。该研究项目的目的是验证一种原本被忽视的蛋白质来源的组成。大部分肌浆蛋白在溶解于加工水中时会丢失，并且与乳清蛋白在乳制品加工过程中的丢弃方式类似。当政府实施有关乳清处理的法规时，乳制品行业的反应是重新利用优质蛋白质供人类使用，现在它是一个价值十亿美元的行业。该研究项目的目的是验证一种原本被忽视的蛋白质来源的组成。