Abstract The effect of different degrees of pre-crystallised lactose (PCL) (0–45%) on the physico-chemical properties of infant formula (IF) containing hydrolysed whey protein was investigated during ageing at two temperatures (25 and 45 °C) and three levels of relative humidity (RH; 11%, 33%, 54%). An increase in the proportion of PCL resulted in higher particle size and higher surface free fat immediately after drying. Lactose crystallisation at RH 54% at both storage temperatures exhibited a logarithmic decline in Tg in IF containing 18% PCL as opposed to exponential decline in IF containing >18% PCL. The degree of PCL directly affected the changes in surface free fat and IF containing 18% PCL and resulted in lowest surface free fat at all ageing conditions. Overall, the proportion of PCL in IF strongly influenced the changes in their physicochemical properties after drying and during storage.

中文翻译：

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乳糖预结晶对含有水解乳清蛋白的婴儿配方奶粉储存过程中理化性质的影响

摘要 研究了不同程度的预结晶乳糖 (PCL) (0–45%) 在两种温度 (25 和 45 °C) 下老化过程中对含有水解乳清蛋白的婴儿配方奶粉 (IF) 理化性质的影响。和三个级别的相对湿度（RH；11%、33%、54%）。PCL 比例的增加导致干燥后立即具有更高的粒度和更高的表面游离脂肪。在 RH 54% 的两种储存温度下，乳糖结晶在含有 18% PCL 的 IF 中表现出 Tg 的对数下降，而不是在含有 >18% PCL 的 IF 中呈指数下降。PCL 的程度直接影响表面游离脂肪和含有 18% PCL 的 IF 的变化，并导致在所有老化条件下表面游离脂肪最低。全面的，