Patent ID: 7244461

Claim:
A method of preparing a smoke extract comprising the steps of: i) preparing a char from wood or cellulose by pyrolysis; ii) placing a portion of the char in a reaction container; iii) obtaining an extraction solvent in its supercritical state, said solvent in its supercritical state being selected from the group consisting of CO 2 , propane, methane, ethylene, ammonia, methanol, and mixtures of one or more of these solvents; iv) maintaining the extraction solvent in its supercritical state at a temperature between 20° C. and 100° C. and at a pressure between 75 and 500 bars. v) bringing the extraction solvent in its supercritical state into intimate contact with the char for a sufficient time to extract a measurable amount of the char and to reduce the amount of benzo(a)pyrene and benzo(anthracene so that the char is safe for use as a food flavoring; vi) removing the solvent from the extracted char from step v); vii) reducing the pressure, in one or more steps, to condense at least a portion of the extracted char in each step of pressure reduction; and viii) collecting the extracted condensed char.