Effect of microwave drying technique on the properties of dried rice food

Abstract

Drying methods are critical determinant in the preparation of dried food because each parameter plays important role in achieving the desired quality. The objective of this study was to investigate the effect of drying conditions of combined oven and microwave drying on the properties of rice-based ready-to-eat dried food. Cooked rice sample (with different ratio of white rice and glutinous rice) was dried by oven at 90°C for 130 min and followed by drying in microwave at various power level (450 and750 W) and time (1, 3 and 5 min). Moisture content and color of the dried rice sample were deter-mined after drying in microwave. The results showed that the dried rice sample using glutinous rice formulation contained the highest moisture content. Moisture content of dried rice decreased with the increase of drying time in microwave. Color analysis shows that mixed white rice and glutinous rice gave the best result of hue angle and chroma value. From this study, it can be concluded that microwave drying technology is a modern technique that can be used for drying of food to extend the shelf-life of food product and shorten the processing time.