We booked a tour to a distillery. We drove out there in a van, passing by fields of blue agave cacti... leaves shooting up smokey metallic blades. Our guide explained that each plant takes eight to twelve years to mature and provides 5 litres of the poison. At harvest time, the leaves and roots are hacked off and the heart retained. Each weighs around 45 kilos at maturity.
She took us to the furnaces where they cook the hearts. There was a mountain of them at the doors... something like giant bloody pineapples... all sticky with red. They're cooked in an oven for a few days and fibrous pulp is excreted as waste. The special juices, however, are drained into great festering vats for fermentation. We stuck our noses over the churning scum and took a breath. Alcohol... overwhelming.
The booze is drained off and distilled two or three times for purity. It attains an alcoholic content of 70% Our guide insisted we try a little and poured it into our hands. She made us take the vow of communion ('... some people are religious', she said.) The stuff wasn't at all bad... very clean tasting, warm. It curbed my hang over nicely. Sadly, a product of such a high potency is never sold to the public. It gets watered down to 40%.
She took us to the storage room piled up with oak barrels. They store it that way to give it flavour. Aged tequilla is not necessarily better than unaged tequilla. Over time the barrels expand and loose alcohol via evaporation and that is why aged tequilla is more pricey... its more expensive to store. Ultimately, the difference between young and old is one of flavour and cost, not of quality.
Finally the time came to sample a few varieties. Now the real measure of quality comes with the constituent proportions of agave to other sugars used in the fermentation process. Tequilla made with 100% blue agave is the most superior and any deviation constitutes a 'mixed' bottle. A 'mixed' bottle may be produced with up to 49% of alternative sugars. Of pure and mixed tequilla, there are two broad varieties. Gold and silver. That is, aged and unaged. We started by trying the 100% stuff of each. I found the silver, which is clear, the more palatable of the two, although both were relatively smooth. Quite unlike my prior experiences of the liquor. Then we had a little of the mixed bottle. This provoked the rank aftertaste and characteristic shivers I was used to. After that we had a prize winning brand (pure agave, aged) and then a little more of the other good stuff. When we caught the van back to town we were humming nicely. The rest of the afternoon was spent in a bar, naturally, gulping down a bit more.