Effect of transpiration drying on discolouration of beech wood during convection drying procedure was studied. In 4 different drying procedures (at temperatures 20 °C and 38 °C, and at relative humidity 33 % and 75 %), colour changes were observed, using CIE L a b system within sections of 25 mm and 50 mm thick elements. The colour of elements, kiln dried immediately after tree felling, was compared to that of elements dried after 16 days transpiration drying. Beech wood after transpiration drying had lower and more homogeneously dispersed moisture. Influence of transpiration drying on drying kinetics was not detected, but it had advantageous effect on colour change. Whole difference in colour and lightness of transpiration dried wood was significantly smaller after all kiln drying procedures. Lower risk of discolouration remained at transpiration drying of beech wood, if the drying procedure had run at higher temperature and lower sharpness.
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