product obtained without a (or with very short) aging process. As well, the spirit must contain 38–55% alcohol content, which is fermented from a wort that contains no less than 51% sugars from the agave plant. Silver/Blanco tequila provides the purest form as little aging has occurred. What is known as gold, joven or oro tequila is usually silver/blanco tequila with the addition of grain alcohols and caramel color; however, some higher-end gold tequilas may be a blend of silver/blanco and reposado. Rested (reposado) or aged tequila (añejo) is aged in wooden containers. The aging process can last between two months and three years and can create or enhance flavors and aromas. The aging process generally imparts a golden color. Flavor and aroma There are more than 300 known compounds in tequila, many of which are produced during the fermentation process, the raw material used, and to a lesser degree during the maturation. The components that make up tequila do not act individually to give tequila its distinctive flavor and aroma, but rather, depend on the interaction and quantity of each volatile compound. The volatile compounds responsible for the flavor and aroma profiles of the tequila are put into a category called organoleptic compounds and are known to increase in concentration with a slower fermentation process. The organoleptic compounds produced during fermentation include higher order alcohols, methanol, esters, carbonyls, terpenes, and furans. Higher-order alcohols have a strong aroma, and the quantity present in each tequila depends on the carbon:nitrogen ratio and temperature during the cooking and fermentation processes. Some of the most common alcohols present other than ethanol are: isoamyl alcohol, isobutanol, and 1-propanol. Methanol is thought to be mainly generated through hydrolysis of methylated pectin which is naturally present in the agave plant, but there has been speculation that it is also partly produced from the enzymatic reactions of yeast strains containing pectin methyl esterase enzyme, which break up the methoxyl group from the pectin. Nearly 50 different esters are identified in tequila, which together give rise to the fruit-like flavors and smell. One of the most abundant esters is ethyl acetate which is synthesized during fermentation by the yeast Saccharomyces cerevisiae, using alcohol transferase enzyme which links acetic acid to ethanol. In general, the longer the controlled fermentation period, the higher yield of esters produced. During the fermentation process, ethanol is oxidized and one of the main compounds