A method for extracting the compound 3-methyl-2H-furo[2,3-c]pyran-2-one from smoke, the method comprising pyrolysis of cellulose or any biomass within a combustion chamber, directing the smoke into a scrubbing apparatus incorporating a spiral condenser tube extending along the chamber and having a number of mist spray units spaced along the entire spiral condenser tube, collecting smoke water thus formed and passing it to a cooling chamber and then to preparation for storage or despatch.