Low‐Temperature Transitions in Fresh and Osmotically Dehydrated Plant Materials
Tóm tắt
Phase transitions in several plant materials were studied using differential scanning calorimetry (DSC) and small oscillatory amplitude rheology. The glass transition temperature of the unfrozen phase, recrystallization peak of water, and melting point of ice, in fresh plant materials as well as in samples osmotically dehydrated in 15, 30, and 45% sucrose solutions, were identified using both thermal and mechanical analysis. Mechanical analysis showed that the glass transition temperature of the unfrozen phase was approximately ‐45°C for fresh and osmotically dehydrated plant materials at all concentrations. Thermal analysis showed that the glass transition of the unfrozen phase in osmotically dehydrated potato samples varied depending on the amount of freeze‐concentration achieved.
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