DECANTER CENTRIFUGATION OF APPLE MASH - EFFECT OF CENTRIFUGE PARAMETERS, APPLE VARIETY AND APPLE STORAGE

Enzyme treated (0.02% Pectinex Ultra SP, 40-degrees-C, 3-4 h) apple mash gave juice yields of 80-90% with suspended solids <3% when decanter centrifuged. Centrifugal conditions were a 230 mm bowl, 5696 rev/min, pool depth of 39 mm and mash temperature of 40-degrees-C. Capacities were 0.33-0.39 kg/s (2600-3100 lb/h) under appropriate conditions for Red Delicious, Spartan, McIntosh and Golden Delicious apples. Storage in air at 0-1-degrees-C for 8 months did not affect machine capacity with Red Delicious and McIntosh varieties but storage of Spartan and Golden Delicious varieties beyond 3-4 months resulted in markedly reduced (half or less) machine capacities. The effects of varying decanter centrifuge settings and problems associated with decanter separation of apple juice are documented and discussed.