is held to significantly stricter standards of chemical purity than what may be allowed in other countries. For example, singani must assay at less than 0.6 mg/L ionic copper whereas many countries that have standards allow 2 to 10 mg/L copper in their liquor products. Fermentation and distillation Grapevines are tended year round, but the fruit is harvested only once a year. Clusters of berries are “groomed” by hand before picking so that only berries that meet published standards are collected. Fermentation produces a “must” or raw wine which is held for distillation. Distillation today uses European batch stills and stainless holding tanks to maintain quality. Stills must not introduce insoluble solids or suspended cellulose as when heated they release odors and affect the aromatic quality of Singani. The stills are also run cold and cut off early to deliver Singani's character. The goal of fermentation is to retain and enhance the characteristic terpenol profile. The goal of distillation is to capture the aromatics while removing nearly all fusel oil. The resulting profile must be just right because barrel aging or blending cannot be used to alter it. Distilled liquor is held for precisely 6 months in clean neutral vessels before bottling so as to allow the aroma profile to intensify. Aging Much of the profile of aged liquor comes from ethanol interacting with wood which produces vanillins and other co-generated compounds. In singani, all of the aromatic profile must come from the grape itself as it interacts with yeast during the fermentation process. A grape richer in desirable aromatics is therefore preferable to thin, acidic varieties as may be used for cognac. Producers who have experimentally aged singani have reported that singani's distinctive character becomes diminished, and the resultant brown liquor tastes more like other brown liquors than singani. Given current national standards, such a liquor could not rightfully be called singani. Congeners As is true for nearly all liquors produced for human consumption, singani comes off the still at a higher proof than it is bottled. This is done to reduce if not eliminate the level of fusel oil. Singani manufacturers take care to keep undesirable substances out of the product so that the characteristic terpenol profile dominates and is not blemished by off-odors such as grassiness (amyl alcohol), pineapple (ethyl butyrate), and other congeners. Occasional public reports stating that singani and its cousin pisco are a “fiery