Effect of Different Drying Conditions on Vacuum Freezing and Microwave-Combined Drying of Pineapple

Bo-Lin Chen; Guan-Syun Lin; Wei-Mon Yan

Authors

Bo-Lin Chen Department of Energy and Refrigerating Air-Conditioning Engineering, National Taipei University of Technology, Taipei 10608, Taiwan
Guan-Syun Lin Research Center of Energy Conservation for New Generation of Residential, Commercial, and Industrial Sectors, National Taipei University of Technology, Taipei 10608, Taiwan
Wei-Mon Yan Research Center of Energy Conservation for New Generation of Residential, Commercial, and Industrial Sectors, National Taipei University of Technology, Taipei 10608, Taiwan

Keywords:

Vacuum freeze drying, vacuum microwave drying, color parameter, rehydration rate

Abstract

In this study, the vacuum freeze and microwave-combined drying is implemented to measure the effect of the microwave power density, moisture content of different transition points, and temperature control of pineapple. Higher microwave power density speeds up the drying process, but it also increases the risk of overheating the sample. The lower the moisture content of transition point, the better the dry sample quality, but the more energy consumption. Enable temperature control prevents sample from overheating during drying process and have high rehydration rates.