Mexico has also a unique alcoholic beverage called Tequila which is made from Agave which is a rich source of inulin, a poly fructosan. There are 130 species of Agave though most commonly used is Agave tequilana. Inulin on hydrolysis yields fructose which is considered sweeter than sucrose. Yeast fermentation is generally carried out using glucose as the source of sugar. Starch sources such as tapioca, maize, rice, wheat sorghum all yield glucose on hydrolysis. On the other hand molasses, a rich source of glucose and fructose, is commercially used to produce alcohol for both industrial and IMF liquors. Mexican producers of Tequila boast of special strains of yeast that converts fructose into alcohol efficiently and is considered a secret.
The process includes roasting, shredding, pressing out the juice, addition of yeast inocculum and fermentation for 30-48 hours followed by distillation in copper stills to get a product of 70-110 proof strength. One kg of Agave pinas yields 1 liter of juice containing 90% inulin. A typical Agave pina weighs 20 to 80 kg. There is always the question as to why this material is not used as a sweetener in food products but its traditional use to make Tequila is based on higher value addition and national pride. Besides use of fructose in foods is clouded with uncertainties regarding its suspected adverse effect in human system. Though it has a low GI of 27, its consumption is reported to be responsible for high triglyceride and LDL levels in human beings. Fructose consumption is also linked to interference with hormone signals associated with satiety leading to over eating. Similarly consumption of fructose after a heavy meal raises its GI value
dramatically. Probably these findings, though not universally accepted, make the Tequila production in Mexico a blessing in disguise as the plentiful supply of Agave is economically utilized!