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The study on microwave irradiation and steam batch process to sterilize oil palm fruits is carried out to investigate their effectiveness on lipase inactivation. The inactivation parameters, palm oil quality, and stripping efficiency were evaluated. Evaluation on the inactivation parameters, such as decimal reduction time (D-value) and kinetic constant (k), were conducted to study the sterilization dependency on time and temperature. Microwave sterilization required only 14.085 to 16.949 minutes to inactivate lipase at temperature of 76.5°C (max), while steam batch sterilization required more than 90 minutes to obtained similar level of free fatty acid (FFA) at higher temperature (80 to 105°C). The quality of palm oil was indicated by the concentration of FFA in palm oil. Sterilization of either by microwave irradiation or steam batch sterilization reduced lipase’s activity significantly, which is indicated by FFA concentration of below 1%. Stripping efficiency from microwave sterilization at various power level after 16 minutes were 27% (medium power level), 58.5% (medium high power level), and 61% (high power level), respectively.

Microwave vacuum and convective hot air dehydration of jackfruit (Artocarpus Heterophyllus) bulbs were carried out to study the effects of different dehydration treatments on drying characteristics, rehydration ability and quality attributes. Jackfruit bulbs were dehydrated by microwave power output of 58, 140, 220, and 321W respectively combined with vacuum level of -65 cmHg during microwave vacuum dehydration. Convective hot air dehydration was also conducted with the hot air temperature of 60, 70, and 80°C, respectively. Microwave vacuum dehydration with microwave power output of 321 W resulted in 133 times faster in drying time compared to convective hot air dehydration with hot air temperature of 60°C. All dehydration data were subjected to Newton and Page’s equation model fitting, where Page’s equation model was well fitted for all dehydration conditions with R2 > 0.994. Furthermore, microwave vacuum dehydration produced better quality of dehydrated jackfruit bulbs with higher rehydration ability and sensory attributes.