” Vanilla extract is a solution containing the flavor compound vanillin as the primary ingredient. Pure vanilla extract is made by macerating and percolating vanilla pods in a solution of ethanol and water. In the United States, in order for a vanilla extract to be called pure, the U.S. Food and Drug Administration requires that the solution contains a minimum of 35% alcohol and 100 g of vanilla beans per liter (13.35 ounces per gallon). Double and triple strength (up to 20-fold) vanilla extracts are available.
Vanilla extract is the most common form of vanilla used today. Mexican, Tahitian, Indonesian and Bourbon vanilla are the main varieties. Bourbon vanilla is named for the period when the island of Réunion was ruled by the Bourbon kings of France; it does not contain Bourbon whiskey.
Natural vanilla flavoring is derived from real vanilla beans with little to no alcohol. The maximum amount of alcohol that is usually present is only 2–3%. Imitation vanilla extract contains vanillin, made either from guaiacol or from lignin, a byproduct of the wood pulp industry.” https://en.wikipedia.org/wiki/Vanilla_extract