Effect of Heat Drying Treatment on Extracts of Sugi ( Cryptomeria japonica ) Board: Quantitative change of terpenes by moderate-temperature drying treatments@@@中温乾燥によるテルペン類の量的変化

To investigate the quantitative change of terpenes in sugi (Cryptomeria japonica) board caused by moderate-temperature drying treatments, extracts of sugi board dried by vacuum, conventional kiln, electric heat and air were analyzed by gas chromatograph/mass spectrometer (GC/MS). Extract samples were prepared at 0-1, 1-2 and 17-18 mm from the surface of dried boards using a planer. The results were as follows. Total content of the extracts detected by GC/MS was less in vacuum-dried board than in air-dried board at all three surface depths. Content of sesquiterpene hydrocarbon at 0-1, 1-2 and 17-18 mm from the surface of vacuum-dried board, at 0-1 and 1-2 mm from the surface of conventional kiln-dried board and at 0-1 mm from the surface of electric heat-dried board was less than in air-dried board. Content of oxygenated sesquiterpene at 0-1 mm from the surface of vacuum-dried board and at 0-1 mm from the surface of conventional kiln-dried board was less than in air-dried board. Content of diterpene hydrocarbon: there were no significant differences between drying treatments. Content of oxygenated diterpene at 17-18 mm from the surface of electric heat-dried board was less than in air-dried board. In conclusion, we showed that a portion of terpenes in sugi board exposed to