Effects of Drying and Storage Temperatures on Volatile Compounds in Shiitake Mushrooms (Lentinus edodes)
S. Piriyaphansakul and G. Srzednicki
Book of Abstract. APEC Symposium on Assuring Quality and Safety of Fresh Produce, August 1-3, 2005, Bangkok, Thailand. 76 page.
2005
บทคัดย่อ
The effects of high temperature drying on shiitake mushroom were investigated. Shiitake mushrooms were dried in a tunnel dryer at four air temperatures regimes, namely 40, 50, 60°C for 24 hr and at 60°C for 12 hr followed by 40°C for 12 hr. Volatile compounds were extracted by Likens and Nikerson apparatus and analysed by gas chromatography-mass spectrometry. Lenthionine is a sulphur compound which is the major volatile compound present in dried shiitake mushrooms as an effect of high temperature. Fresh shiitake mushrooms exhibit only a slight odour but upon drying, a characteristic sulfurous aroma gradually develops. Lenthionine was present after drying at 50, 60°C for 24 h and 60°C for 12 hr followed by 40°C for 12 hr. It appears that lenthionine content was gradually increasing following the increase of drying temperature. However, exposure to a constant temperature for prolonged time led to its destruction. Thus, drying at 60°C for 12 hr followed by 40°C for 12 hr resulted in a higher lenthionine concentration than other drying temperatures and a lower cost than drying at 60°C for 24 hr. Therefore, the optimum temperature for drying and storage of shiitake mushrooms was found to be 60°C for 12 hr followed by 40°C for 12 hr and storage at 30°C. Although storage at 20°C resulted in a higher concentration of some volatiles (but not all), storage at 30°C would be a better option for the weather conditions prevailing in