Adebowale Yemisi A, Adebowale Kayode O
Department of Food Science and Technology, Federal University of Technology, Akure, Nigeria.
Int J Biol Macromol. 2007 Jan 30;40(2):119-25. doi: 10.1016/j.ijbiomac.2006.06.016. Epub 2006 Jun 27.
The influence of chaotropic and kosmotropic salts on Mucuna pruriens protein isolates was investigated. Protein solubility profile indicated that solubility was minimal at the isoelectric point of the protein isolate (4.0) while the solubility was maximal at pH 10.0 in all salt solutions. Chaotropes (I(-), ClO(4)(-) and SCN(-)) exhibit better protein solubility than the kosmotropes (SO(4)(2-), Cl(-) and Br(-)). Increase in protein solubility follows the Hofmeister series: NaSO(4)<NaCl<NaBr<NaI<NaClO(4)<NaSCN. Maximal water absorption capacity was recorded at low concentration of all the salts (0.1M). The water absorption capacity reduced as the concentration of the salts was increased to 2.0M. Kosmotropic salts exhibited better water absorption capacity than chaotropic salts. Both foaming capacity and stability were better in chaotropic salts compared with kosmotopic salts. Maximal foam capacities and stability were observed in protein solutions at 0.1M concentration. However the foam capacity and stability decreased as the concentration was increased further to 2.0M. The result indicates that emulsion activity index (EAI) and emulsion stability index (ESI) was reduced as the concentration of salts in each protein solution was increased. Protein solutions which contained NaSCN exhibited the highest emulsifying properties while those in Na(2)SO(4) recorded the lowest emulsifying properties. In addition, chaotropic salts had better emulsifying properties compared with kosmotropic salts. Increase in emulsifying activity follows the Hofmeister series. The least gelation concentration increased as the concentration of the salts increased. However chaotropic salts exhibited better gelation properties than kosmotropic salts.
研究了离液盐和促溶剂盐对刺毛黧豆分离蛋白的影响。蛋白质溶解度曲线表明，在蛋白质分离物的等电点（4.0）时溶解度最小，而在所有盐溶液中pH 10.0时溶解度最大。离液盐（I⁻、ClO₄⁻和SCN⁻）比促溶剂盐（SO₄²⁻、Cl⁻和Br⁻）表现出更好的蛋白质溶解性。蛋白质溶解度的增加遵循霍夫迈斯特序列：Na₂SO₄＜NaCl＜NaBr＜NaI＜NaClO₄＜NaSCN。在所有盐的低浓度（0.1M）下记录到最大吸水能力。随着盐浓度增加到2.0M，吸水能力降低。促溶剂盐比离液盐表现出更好的吸水能力。与促溶剂盐相比，离液盐的起泡能力和稳定性更好。在0.1M浓度的蛋白质溶液中观察到最大泡沫容量和稳定性。然而，随着浓度进一步增加到2.0M，泡沫容量和稳定性降低。结果表明，随着每种蛋白质溶液中盐浓度的增加，乳化活性指数（EAI）和乳化稳定性指数（ESI）降低。含有NaSCN的蛋白质溶液表现出最高的乳化性能，而含有Na₂SO₄的溶液记录到最低的乳化性能。此外，与促溶剂盐相比，离液盐具有更好的乳化性能。乳化活性的增加遵循霍夫迈斯特序列。最低凝胶化浓度随着盐浓度的增加而增加。然而，离液盐比促溶剂盐表现出更好的凝胶化性能。
