Abstract Acid casein powder was used to prepare caseinate solutions (27 g/kg) with different ionic milieus: sodium caseinate (NaCN, I ∼0.015 mol/L) and calcium caseinate (CaCN, I ∼0.03 mol/L) were obtained by neutralisation with NaOH and Ca(OH)2, respectively, and dissolving in phosphate buffer resulted in a high ionic strength caseinate solution (CN-PB, I ∼0.16 mol/L). Treatment with microbial transglutaminase (mTGase) for defined incubation times lead to different extents of casein cross-linking, which were characterised by size exclusion chromatography and the N-e-(γ-glutamyl)-lysine isopeptide content (IC). Maximum polymer size was reached at ∼90% casein polymerisation, and increased in the order NaCN

中文翻译：

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酶交联酪蛋白酸盐在不同离子环境中的酸诱导凝胶化

摘要 酸性酪蛋白粉用于制备不同离子环境的酪蛋白酸盐溶液（27 g/kg）：中和得到酪蛋白酸钠（NaCN，I ∼0.015 mol/L）和酪蛋白酸钙（CaCN，I ∼0.03 mol/L）分别用 NaOH 和 Ca(OH)2 溶解在磷酸盐缓冲液中，产生高离子强度的酪蛋白酸盐溶液（CN-PB，I ∼0.16 mol/L）。用微生物转谷氨酰胺酶 (mTGase) 处理确定的孵育时间会导致不同程度的酪蛋白交联，其特征在于尺寸排阻色谱和 Ne-(γ-谷氨酰)-赖氨酸异肽含量 (IC)。最大聚合物尺寸在约 90% 酪蛋白聚合时达到，并以 NaCN 的顺序增加