Factors Influencing the Incorporation of 2AP in Fluidized Bed Drying Processes
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Abstract
Drying high-moisture paddy rice while retaining the quality of the grains and their natural aroma is one of the hardest things to perform in industrial processing. This study examines a hybrid drying system comprising drying units from Louisiana State University (LSU), a fluidized bed dryer, and a cyclone-based hot-air generator to reduce paddy moisture content from 25–30% to the safe storage level of 14% on a wet-basis. The cyclone furnace heated the air to 280°C using leftover charcoal. Before entering the fluidized bed dryer, the air was cooled to 101.7 °C. The grain's temperature was kept below 57.7 °C during this time, which helped preserve the rice's quality. After the rice had dried out a bit, it was put in six LSU (Louisiana State University) drying chambers. Each chamber could hold 37.5 tons of rubbish every hour and worked in groups for 10 hours. The procedure worked well to lower the moisture level in a single step, even when it reached 18%. By eliminating the middle resting stage, the drying process is easier and faster without affecting the final product's quality. The dried rice had 10.7% moisture, a grain temperature of 36.9°C, and 4.15 µg/g of 2-acetyl-1-pyrroline (2AP). This means that the rice still smelled good. These results show that using fluidized bed drying with LSU drying is a good approach to make large-scale commercial drying systems work better and be simpler while maintaining excellent rice quality.
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