The dried taro slices were obtained at water content below 0.11kg water/kg dry solids using hot-air drying(AD), microwave drying (MWD), microwave vacuum drying (MWVD), Freeze drying (FD). The chosen drying methods provided wide variation in residence time, from 15min (in MWD) over 14h (in FD). The influence of drying conditions and various drying methods on the polysaccharide content, color, shrinkage, sensory evaluation and micrographs of dried taro slices was studied. The colors of AD dried taro slices were comparable to the MWVD slices, but were significantly different from MWD (darker) and FD (lighter) counterparts. MWVD and VFD of dries taro slices were higher than AD and MWD in terms polysaccharide content, moreover, there are no significant differences between MWVD and FD. The microstructure of FD and AD dried taro slices was smooth and flaky, Particles of FD-dried taro slices were porous compared to the other three products. The study concludes that MWVD drying can produce taro slices with quality comparable to that obtained via freeze drying, and better than the MW and AD-dried taro slices.
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