Abstract: In order to reduce the drying time and at the same time to improve the quality of dried bamboo shoots, a combined microwave-hot air drying process was developed and optimized by examining the effect of microwave drying time and power and hot air drying temperature on sensory score, total drying time, rehydration rate, color difference and hardness using a combination of single factor method and central composite design coupled with response surface methodology. The results showed that the optimal drying conditions were as follows: microwave power, 6.3 W/g; microwave drying time, 60 s; and hot air drying temperature, 65 ℃. Under these conditions, the sensory score of dried bamboo shoots was 85.6 points, the total drying time was 200 min, and the rehydration rate was 6.17; the color difference ΔE* and hardness were 19.99 and 19 511.23 g, while those of the rehydrated product were 13.92 and 20 010.71 g, respectively. The proposed drying process will be of great significance to the future development of the bamboo shoot industry.

Key words: bamboo shoots, response surface methodology, microwave, hot air, drying