Lerici C R
S TA NU. 1976 Jan-Feb;6(1):27-32.
In this work the results obtained during freeze-drying of a food model gel are reported. The model system was constituted by 12,5% sucrose, 2,5% pectin and five organic volatile substances: acetone, ethyl acetate, methanol, ethanol and n-propanol. In particular, it was studied the effect of granulation and the effect of frozen material thickness on retention of volatiles. Other experiments were made to study volatiles distribution inside the freeze-dried materials; the stripping action of warm air and of water vapor flux through the freeze-dried layers, and eventually the holding capacity of dried layers to "capture" the volatiles. All the data suggested a theory about the different mechanisms which influence the retention and the remotion of volatiles during freeze-drying of foods.
本文报道了食品模型凝胶冷冻干燥过程中获得的结果。该模型体系由12.5%的蔗糖、2.5%的果胶和五种有机挥发性物质组成：丙酮、乙酸乙酯、甲醇、乙醇和正丙醇。特别研究了造粒的影响以及冷冻物料厚度对挥发性物质保留的影响。还进行了其他实验来研究冷冻干燥物料内部挥发性物质的分布；热空气和水蒸气通量通过冷冻干燥层的汽提作用，以及干燥层“捕获”挥发性物质的容纳能力。所有数据都提出了一种关于在食品冷冻干燥过程中影响挥发性物质保留和去除的不同机制的理论。
