The heat transfer film coefficient of orange juice (OJ) during pasteurization using a plate heat exchanger with intermating 316 SS plates was studied. Mathematical models to predict OJ heat transfer film coefficient are presented. The OJ density was measured using an in-line density sensor at pasteurization temperature and also measured off-line by hygrometer at different temperatures. The OJ viscosity was measured by an off-line instrument, in the temperature range from 5-90°C. The mean values of OJ density and OJ
viscosity at 20°C were 1046.0 3.6 kg/m3 and 14.17 4.75 mPa s, respectively. The values of heat transfer film coecient for OJ
varied from 983 to 6500 W/m2 °C, whereas the water heat transfer film coefficient varied from 8387 to 24245 W/m2 °C. This study
has provided a suitable heat transfer correlation to predict the OJ heat transfer film coefficient as a function of its viscosity and the
channel velocity, that is, this correlation is independent of the plate geometry, for varied conditions of OJ pasteurization
process. 1999 Elsevier Science Ltd. All rights reserved