Allan Matthew, Mauer Lisa J
Department of Food Science, Purdue University, 745 Agriculture Mall Drive, W. Lafayette, IN 47907, USA.
Department of Food Science, Purdue University, 745 Agriculture Mall Drive, W. Lafayette, IN 47907, USA.
Food Chem. 2016 Mar 15;195:29-38. doi: 10.1016/j.foodchem.2015.05.042. Epub 2015 May 12.
Many crystalline food ingredients undergo dissolution at a critical relative humidity known as the deliquescence point (RH0). Blends of crystalline ingredients exhibit deliquescence lowering, resulting in a deliquescence point (RH0mix) lower than the individual ingredient RH0s. To determine the effects of method type and data collection parameters, these deliquescence measurement methods were compared: saturated solution water activity, dynamic vapor sorption profiles (DVS), and dynamic dewpoint sorption profiles (DDI). Water activity measurements were broadly applicable for measuring deliquescence points when 1-4 g sample, 50-125 μL/g water:solid ratio, and 24-48 h equilibration were used. DVS and DDI techniques should be limited to samples containing 1-2 ingredients due to crystal contact point effects on RH0mix measurement. Recommended DVS parameters are: 1% RH step, 0.01% equilibrium criteria, and 3h maximum time. DDI profiles were consistent with 50-150 mL/min vapor flow rates. Ingredient mutarotation, solute interactions in solution, and contact point limitations affect the determination of deliquescence points.
许多结晶食品成分在一个被称为潮解点（RH0）的临界相对湿度下会发生溶解。结晶成分的混合物表现出潮解降低，导致潮解点（RH0mix）低于各个成分的RH0。为了确定方法类型和数据收集参数的影响，对这些潮解测量方法进行了比较：饱和溶液水分活度、动态蒸汽吸附曲线（DVS）和动态露点吸附曲线（DDI）。当使用1-4克样品、50-125微升/克水与固体的比例以及24-48小时平衡时间时，水分活度测量广泛适用于测量潮解点。由于晶体接触点对RH0mix测量的影响，DVS和DDI技术应限于含有1-2种成分的样品。推荐的DVS参数为：1%RH步长、0.01%平衡标准和最长3小时时间。DDI曲线与50-150毫升/分钟的蒸汽流速一致。成分的变旋、溶液中的溶质相互作用以及接触点限制会影响潮解点的测定。
