Abstract The effect of CaCl2 addition (2–72 mmol L−1) on selected properties of acid-rennet gels was investigated. Salt content in milk significantly altered the microstructure of gels as observed using scanning electron microscopy. Gels with higher content of CaCl2 (≥54 mmol L−1) showed more homogeneous protein network with smaller pore sizes and thus increased water holding capacity and lower cohesiveness. Fractal analysis indicated that the surface of the internal gel structure was rather irregular (fractal dimensions > 1). As revealed by atomic absorption spectrometry, demineralisation was significant and typical of coagulation caused by the presence of lactic acid that could probably cause nonsignificant correlation between calcium content in curd and some of its properties, i.e., syneresis. With the addition of 4 mmol L−1 CaCl2 to milk, a slight increase in total calcium content in the resulting curds gave a significant increase in acid-rennet gel firmness.

中文翻译：

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添加氯化钙对酸凝乳酶凝胶性能的影响

摘要 研究了 CaCl2 添加 (2–72 mmol L-1) 对酸凝乳酶凝胶选定特性的影响。使用扫描电子显微镜观察到，牛奶中的盐含量显着改变了凝胶的微观结构。CaCl2 含量较高（≥54 mmol L-1）的凝胶显示出更均匀的蛋白质网络，孔径更小，从而增加了持水能力和降低了内聚力。分形分析表明内部凝胶结构的表面相当不规则（分形维数 > 1）。正如原子吸收光谱法所揭示的，脱矿质是显着的，并且是由乳酸的存在引起的凝结的典型特征，这可能导致凝乳中的钙含量与其某些特性（即脱水收缩）之间存在不显着的相关性。在牛奶中加入 4 mmol L−1 CaCl2，