IN-LINE SURFACE DRYING OF WET KIWIFRUIT

An experimental study was undertaken to determine the most effective and commercially viable method for in-line surface drying of wet kiwifruit in a pack line operation before the grading table. The study involved blowing air of specified temperatures, relative humidities and velocities over individual wet kiwifruit and monitoring their change in weight as the water evaporated. Initial fruit temperature averaged 15 C. Warm air and cool air drying conditions were considered. Evaluation of the results in relation to simple drying theory showed that when the fruit temperature was lower than the wet bulb temperature of the ventilating air, evaporation was lower than predicted. Conversely when the fruit temperature was higher than wet bulb, evaporation was greater. For kiwifruit in the range of 10 – 20 C, we can now predict the rate of evaporation of water under any likely conditions.