Abstract To keep their functional properties, it is crucial that protein aggregates maintain their structure after spray drying and that the powders can be fully rehydrated. In this study, microgels and fractal aggregates were prepared by heating a mixture of milk serum protein concentrate and lactose (40/60; %, w/w) at 85 °C for 15 min by varying the pH. Various fractions of native proteins were added to the systems prior to spray drying. This study showed that microgels and fractal aggregates kept their structure after spray drying and reconstitution. The particle morphology could be correlated to the stiffness of the interface of the feed droplet. The forced imbibition rate showed a negative correlation with increasing amount of aggregated proteins in the powders that seems to be a result of denatured/aggregated proteins present at the surface. These findings are of importance for the formulation of spray-dried powders with improved rehydration characteristics.

中文翻译：

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喷雾干燥微凝胶和具有不同比例天然乳清蛋白的分形聚集体的颗粒形态和再水化特性

摘要 为了保持其功能特性，蛋白质聚集体在喷雾干燥后保持其结构以及粉末可以完全再水化是至关重要的。在这项研究中，通过改变 pH 值，在 85 °C 下加热乳清蛋白浓缩物和乳糖（40/60；%，w/w）的混合物 15 分钟，制备了微凝胶和分形聚集体。在喷雾干燥之前，将各种部分的天然蛋白质加入到系统中。该研究表明，微凝胶和分形聚集体在喷雾干燥和重构后保持其结构。颗粒形态可能与进料液滴界面的刚度相关。强制吸入率与粉末中聚集蛋白质的增加呈负相关，这似乎是表面存在变性/聚集蛋白质的结果。