Acid whey from Greek-style yogurt (GSY) is prone to fouling during concentration by reverse osmosis (RO), a phenomenon credited to its high calcium concentration. In this work, we sought to optimize the demineralization of GSY acid whey through precipitation of Ca by addition of base (NaOH) and phosphate salts. The effects of pH (6–10), calcium-to-phosphorus (Ca/P) ratio (0.3–1.3), temperature (40–70 °C), and holding time (10–60 min) GSY whey decalcification were evaluated using response surface methodology (RSM). Ca precipitation ranged from 62 to 97% and was significantly affected by pH and the Ca/P ratio. Optimal conditions for Ca removal were pH ≥ 9 and a Ca/P ratio of 0.55. Surprisingly, no improvement in RO flux was observed for GSY whey following decalcification.

来自希腊式酸奶 (GSY) 的酸性乳清在通过反渗透 (RO) 浓缩过程中容易结垢，这种现象归因于其高钙浓度。在这项工作中，我们试图通过添加碱 (NaOH) 和磷酸盐沉淀 Ca 来优化 GSY 酸乳清的脱矿质。评估了 pH (6–10)、钙磷 (Ca/P) 比 (0.3–1.3)、温度 (40–70 °C) 和保持时间 (10–60 分钟) GSY 乳清脱钙的影响使用响应面方法 (RSM)。Ca 沉淀的范围为 62% 到 97%，并且受 pH 值和 Ca/P 比的影响很大。去除 Ca 的最佳条件是 pH ≥ 9 和 Ca/P 比为 0.55。令人惊讶的是，脱钙后的 GSY 乳清没有观察到 RO 通量的改善。