Controlled Low‐Temperature Vacuum Dehydration–A New Approach for Low‐Temperature and Low‐Pressure Food Drying

ABSTRACT The processes of freeze‐drying, vacuum drying and controlled low‐temperature vacuum dehydration (CLTV) were used to dry clam paste and a gelatin‐microcrystalline cellulose model food system. CLTV was carried out as cold as possible without freezing the product. Much less drying time was required for CLTV and vacuum drying than for freeze‐drying. The mass transfer resistance for both freeze‐drying and CLTV was less than that of vacuum drying. Functional properties were closer to those of freeze‐drying than to vacuum drying. CLTV versus freeze‐drying showed a 30% reduction in enthalpy change and 40% reduction in running cost. Microbiological analysis, used to monitor the safety of processing clam paste, showed that the process was satisfactory relative to common parameters.