Effects of different drying methods on the quality of lotus root chips

ABSTRACT: In order to determine the best drying method for leisure lotus root crisp slices, six different drying methods were adopted, including hot air drying,microwave drying equipment, hot air-vacuum microwave drying, hot air-air puffing drying, vacuum Microwave-Air puffing drying, hot air-vacuum Microwave-Air puffing drying. After drying, the quality indexes such as color, shrinkage, hardness, brittleness, VC retention, polyphenol retention and microstructure were analyzed.
microwave drying equipment

The results showed that hot air drying had little effect on the color of lotus root crisp slices, but the hardness was too low, brittleness was poor, VC and polyphenol loss was the most serious; vacuum microwave drying lotus root crisp slices VC and polyphenol retention rate was high, brittleness was good, but the hardness was too high, 

product shrinkage was serious, color difference and browning were high; The quality of lotus root crisp slices was better than that of single drying. The shrinkage and browning degree of lotus root slices dried by hot air-vacuum Microwave-Air puffing were significantly lower than that dried by vacuum microwave drying, while the retention rate of VC and polyphenols was significantly higher than that dried by hot air drying. The hardness, brittleness were moderate and the porosity was good. To sum up, hot air-vacuum Microwave-Air puffing drying is the most suitable method for processing lotus root leisure crisp slices.
 lotus root microwave drying