This study aimed to find the optimum conditions of garlic drying by microwave and hot air combination. The influence factors of microwave power density and hot air temperature were investigated using the drying rate, allicin content, sensory quality, whiteness, rehydration ratio and comprehensive scores were chosen as indexes. The combined drying conditions were optimized through L9 (33) orthogonal test with microwave power density, moisture content of conversion point and hot air temperature as experimental factors. The results showed that the comprehensive scores of garlic dried under microwave power at 9.2 W/g and hot air at 70 ℃ were 94.698 and 96.566, respectively. The overall score of garlic was significantly influenced by microwave power density (p＜0.01) but not significantly influenced by the conversion point of moisture content and hot air temperature (p＞0.05). The optimum conditions of combined microwave and hot air drying were 9.2 W/g microwave to 1.200 g/g moisture content of conversion point, then 60 ℃ hot air drying to 0.100 g/g moisture content. Under these optimum conditions, the content of allicin, rehydration ratio, whiteness, sensory evaluation and comprehensive score were 0.956 mg/g, 2.699, 83.130, 83.000 and 125.281, respectively. Therefore, microwave drying followed by hot air drying was a better method and quite suitable for garlic drying.
LI Xiang-li
,
LIU Jing
,
HOU Yi-chao
,
ZHU Le-le
,
MA Long-chuan
. Optimization of garlic drying method by microwave and hot air combination[J]. Food and Fermentation Industries, 2018
, 44(11)
: 237
-244
.
DOI: 10.13995/j.cnki.11-1802/ts.016362
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