Synthetics
Vanillin propylene glycol acetal smells like a slightly sweet, vanilla-like aroma with a hint of chemical undertones.
Mosciano, Gerard P&F 25, No. 1, 49, (2000): Sweet, vanillin, slightly powdery with phenolic cocoa nuances
Luebke, William tgsc, (1984): Sweet vanilla chocolate creamy dairy powdery
Bedoukian Research: Sweet, vanilla
Used in place of vanillin, this material is stable in an alkali environment with little discoloration.