What is imitation vanilla made from?

Several methods are used to make imitation vanillin, including the most popular, which involves synthesizing the petrochemical guaiacol. Other methods, used more in the past, have included synthesizing vanillin from the eugenol found in clove oil, and synthesizing the lignin byproduct of a process used to make wood pulp.

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Although the idea of a synthetic flavoring may not sound so appealing, you may prefer it to another (extremely expensive) vanilla imitator – castoreum. Extracted from the scent glands (situated next to the anal glands) of the North American Beaver, castoreum is sometimes found in very high-end vanilla-, raspberry-, and strawberry- flavored items, and is usually included on food labels in the United States as “natural flavoring.” Don't worry though, this natural flavoring is probably used in your perfume, not your extracts!