การอบแห้งเมล็ดกาแฟจากกระบวนการแห้งโดยใช้เครื่องอบแห้งชีวมวล

Abstract

The purpose of this research are to investigate the drying strategy of fresh coffee beans until it reaches the safe moisture content for preservation before sun drying and also to find the drying performance. This is because of coffee beans (Cherries) after harvest drying should begin as quickly as possible to reduce the moisture content of cherries and solar drying is often used gives a greater transfer of flavor from flesh to pit of the cherries to achieve an excellent coffee flavor. If coffee beans cannot be dried on time, the quality degrades. Therefore, the first period of drying using dryer is needed to extend the shelf life. From the drying experiment using a biomass dryer, the drying temperature of 50°C-70°C for 4-6 h. Coffee beans with an initial moisture content (220-240% dry- basis) were dried until final moisture content (90% dry-basis). It was the water activity of 0.95 is appropriate to decrease fungal growth and extend the shelf life for a short time before solar drying process. The temperature distribution in the drying room, the right and the middle are higher than the left. Because there are above the kiln. The result shown that the specific energy consumption in the range of 25-47 MJ/kgwater overall efficiency was 5-10%, This produced color similar to all experiments.