SUMMARYA sugar‐free maple flavor concentrate made by extracting maple sirup with chloroform has been found to contain vanillin, syringaldehyde, and dihydroconiferyl alcohol, aromatic compounds related to lignin. When a chloroform extract of the sap of the maple tree is subjected to alkaline hydrolysis and nitrobenzene oxidation, the amounts of vanillin and syringaldehyde increase. The amount of dihydroconiferyl alcohol in this sap extract increases upon alkaline hydrolysis and then decreases upon subsequent nitrobenzene oxidation. Nitrobenzene oxidation of lignin‐like material in the sap yields vanillin as the chief reaction prod
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