Parchment Coffee Drying Using Microwave Combined with Hot Air: doi: 10.14456/mijet.2017.11

Lamul Wiset; Nattapol Poomsa-ad

Authors

Lamul Wiset Mahasarakham University
Nattapol Poomsa-ad Mahasarakham University

Keywords:

parchment coffee, microwave-hot air combination drying, quality

Abstract

We studied the kinetics of parchment coffee dried by microwave combined with hot air and assessed the coffee quality. Coffee beans with initial moisture content of 55%wet basis were dried to a moisture content of 10% wet basis. Drying temperatures between 60◦C and 80◦C and microwave powers from 600 to 800 W were examined. Coffee quality was assessed by the electric conductivity test: increase in both temperature and microwave power led to increasing electric conductivity. Drying at60◦C with 600W microwave power had the lowest electric conductivity of 276 micro cement per centimeter per gram. Drying at 60◦C combined with 800W microwave power showed the lowest energy consumption of 18.7 kW-hours for a 98 minute drying time. The highest energy consumption was 26.6 kilowatt-hours at 60◦C and 600W microwave power for a 145 minute drying time. Thus, considering both energy consumption and quality, drying at 60◦C combined with 800W microwave power is recommended.

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