Food Hydrocolloids Research Center, Department of Food Science and Technology, Ferdowsi University of Mashhad, PO Box: 91775-1163, Mashhad, Iran.
Int J Biol Macromol. 2012 Oct;51(3):235-43. doi: 10.1016/j.ijbiomac.2012.05.018. Epub 2012 May 23.
The interaction between hydrocolloids and solvent/cosolutes are the predominant factors determining their functional properties in food systems. In this research, the influence of different temperatures, salts and sugars were investigated on some molecular parameters of Balangu seed gum (BSG) as a new potential source of hydrocolloid. The results revealed that BSG has a high molecular weight (3.65 × 10(6)g/mole) and intrinsic viscosity (7236.18 ml/g), rather flexible chain with a chain flexibility parameter of 1156.53, low stiffness parameter (0.346 for Na(+) and 0.507 for Ca(2+)) and hydrogel content (46%). It was observed that except for water, the solutions of different salts (NaCl and CaCl(2)) and sugars (sucrose and lactose) are poor solvents for BSG as indicated by a monotonous decrease in intrinsic viscosity, swollen specific volume, shape function, hydration parameter, and coil dimensions. The parameters representing the interactions of BSG molecules with different cosolutes, i.e. hydrogel content and Huggins constant, were observed to increase significantly as the ionic strength and sugar concentrations increased from 0.005 to 0.05 M and 2.5 to 40% w/v, respectively. In addition, the elevated temperatures (20-50 °C) induced a clear contraction in BSG dimensional and shape parameters along with a decrease in solvent quality and the extent of associated water molecules through hydrogen bonds and/or physical entrainment. These results may be of high significance when considering the influence of major additives generally used in food products, such as various salts and sugars, and/or frequent processing parameters like temperature on rheological and functional points of view.
水凝胶与溶剂/共溶剂的相互作用是决定其在食品体系中功能特性的主要因素。在这项研究中，研究了不同温度、盐和糖对作为新型水凝胶潜在来源的巴兰果种子胶（BSG）的一些分子参数的影响。结果表明，BSG 具有高分子量（3.65×10^6g/mol）和特性粘度（7236.18ml/g），相对较软的链，链柔性参数为 1156.53，低刚性参数（Na+为 0.346，Ca2+为 0.507）和水凝胶含量（46%）。结果表明，除水外，不同盐（NaCl 和 CaCl2）和糖（蔗糖和乳糖）溶液均为 BSG 的不良溶剂，这表现为特性粘度、溶胀比容、形状函数、水合参数和链尺寸单调下降。与不同共溶剂相互作用的参数，即水凝胶含量和哈金斯常数，随着离子强度和糖浓度从 0.005 增加到 0.05M 和 2.5 增加到 40%w/v，分别显著增加。此外，升高的温度（20-50°C）导致 BSG 尺寸和形状参数明显收缩，溶剂质量降低，氢键和/或物理夹带的缔合水分子数量减少。当考虑到食品产品中通常使用的主要添加剂（如各种盐和糖）以及频繁的加工参数（如温度）对流变学和功能特性的影响时，这些结果可能具有重要意义。
