Department of Dairy Technology, Institute of Food Technology and Nutrition, College of Natural Sciences, University of Rzeszow, Ćwiklińskiej 2D, 35-601 Rzeszów, Poland.
Molecules. 2021 Sep 13;26(18):5563. doi: 10.3390/molecules26185563.
The aim of this study was to determine the effect of adding calcium compounds to processed goat's milk, and on the properties of acid rennet goat's milk gels, which are a middle product obtained in the manufacture of acid rennet cheese. The properties of the gels directly affect the quality of acid rennet cheeses. The analysis of raw goat's milk was carried out, then acid rennet gels were produced with the addition of six different calcium compounds (chloride, citrate, bisglycinate, gluconate, lactate, and carbonate). The dynamics of milk fermentation were performed by monitoring the pH value of milk during acidification. The pH, syneresis, color, and texture profile were determined in the formulated acid rennet gels. An organoleptic evaluation was also performed. The study demonstrated that, not only calcium chloride, but also calcium citrate, gluconate, lactate, bisglycinate, and calcium carbonate could be used in the production of goat's milk acid rennet gels, or the middle product in the manufacture of acid rennet curd cheese from goat's milk. Notably, the addition of citrate, bisglycinate, and calcium carbonate in doses of 20 mg Ca 100 g most effectively reduced syneresis compared to the control sample by 4.76% (citrate), 7.85% (bisglycinate), and 10.28% (carbonate). The hardness of the control gels ranged from 2.35 N to 2.99 N. The addition of chloride, citrate, gluconate, lactate, and calcium carbonate to the milk improved the acid rennet gel's hardness. The addition of 20 mg Ca 100 g as gluconate increased the hardness the most (3.61 N). When increasing the calcium dosage in the form of all compounds, there was a tendency to increase the gel's springiness. The addition of chloride, citrate, and bisglycinate to milk did not result in a darkening of the gel's color. The addition of calcium compounds mostly reduced the intensity of goatish taste and odor. Calcium gluconate, in particular, reduced the goatish taste the most, a taste which is not always acceptable by the consumers.
本研究旨在确定在加工山羊奶中添加钙化合物对酸凝乳羊奶凝胶特性的影响，酸凝乳羊奶凝胶是在酸凝乳奶酪生产过程中获得的中间产物。凝胶的性质直接影响酸凝乳奶酪的质量。对原料羊奶进行了分析，然后在添加六种不同钙化合物（氯化物、柠檬酸盐、双甘氨酸盐、葡萄糖酸盐、乳酸盐和碳酸盐）的情况下生产酸凝乳凝胶。通过监测酸化过程中牛奶的 pH 值来监测牛奶的发酵动力学。在配方酸凝乳凝胶中测定 pH 值、离水率、颜色和质地特性。还进行了感官评价。研究表明，不仅氯化钙，而且柠檬酸钙、葡萄糖酸钙、乳酸钙、双甘氨酸钙和碳酸钙也可用于生产山羊奶酸凝乳凝胶，或用于从山羊奶中生产酸凝乳干酪的中间产物。值得注意的是，与对照样品相比，柠檬酸、双甘氨酸和碳酸钙以 20mgCa100g 的剂量添加可分别将离水率降低 4.76%（柠檬酸）、7.85%（双甘氨酸）和 10.28%（碳酸钙）。对照凝胶的硬度范围为 2.35N 至 2.99N。向牛奶中添加氯化物、柠檬酸盐、葡萄糖酸盐、乳酸盐和碳酸钙可提高酸凝乳凝胶的硬度。以葡萄糖酸盐形式添加 20mgCa100g 可最大程度地提高凝胶的硬度（3.61N）。当以所有化合物的形式增加钙用量时，凝胶的弹性有增加的趋势。向牛奶中添加氯化物、柠檬酸盐和双甘氨酸不会使凝胶颜色变暗。添加钙化合物大多可降低羊奶的味道和气味强度。葡萄糖酸钙尤其能最大程度地降低羊奶的味道，而这种味道并不总是为消费者所接受。
