Abstract: Vacuum frying, atmospheric frying, freeze drying, microwave drying, hot air drying and microwave-vacuum frying-hot air drying were used separately to prepare crispy mushroom from fresh shiitake to study the effect of drying methods on the quality of crispy mushroom. The results showed that the crispy mushroom obtained from vacuum frying exhibited large interior holes, good texture, aroma and taste but dark color. Freeze drying provided the minimum volume shrinkage rate of fresh shiitake resulted in more internal holes distributed more evenly and the best sensory quality. The crispy mushroom obtained from microwave-vacuum frying-hot air drying revealed the maximum crispiness, but more serious volume shrinkage when compared to that obtained from vacuum frying and poorer sensory quality when compared to that obtained from freeze drying. The crispy mushroom obtained from atmospheric frying had better aroma, but worse texture, color and crispiness, and high fat content. The crispy mushrooms obtained from microwave drying or hot air drying exhibited compact interior structure, poor crispiness, and the most serious volume shrinkage, and bad sensory quality. The best overall quality of crispy mushroom could be achieved by vacuum frying or freeze drying.

Key words: drying methods, mushroom, crispness, shrinkage rate, color, microstructure, quality