Distilling Feni Liquor – Chemistry in the Copper Pot

The process of crafting a Feni is in many ways very similar to that of making a wine. You hand pick tree ripened cashews, stomp the juicy apples andallow the juice to ferment into a crude cashew wine. But that’s probably wherethe similarity ends. In the following step- distillation, the low-strength wine is converted into a high strength alcoholic spirit, that we could call an Urrack, Cazulo or a Feni, depending on which stage you are at.

Feni distillation is often simplified as a process of separating the alcohol from the rest of the wine- rather alcohol evaporating faster than water in the Wash. But in fact, when the wash is brought to a boil, a lot of complexinteractions take place between the many components inside the bhann- thecopper pot, and alcohol evaporation is only one of them.

If you have ever tasted fermented cashew wash; it has a rather mustytang to it, notes which are not entirely pleasant to taste. However, comparedto the wash, Feni has distinctive flavours and taste that has so much appeal –practically impossible to detect in the wash. So how does this transformationcome about?

The metabolism of the naturally present wild yeast is an enormouslycomplex process- converting natural sugars into a mixture of different alcoholsand organic acids. With the addition of heat during distillation, thesemixtures of different alcohols and organic acids recombine to form chemicalcompounds called esters. The aromasin a Feni are tied to esters. Different kinds of alcohol and different acids give differentrise to different esters- consequently widening the flavour profile of thedrink. It but natural that a little water also gets vaporized when the heat is applied, and it is on these water vapours that esters piggy back on to betransported  and then condensed into the launi- or distillate collection pot. By redistilling the first distillate,Urrack with fresh juice, we only are trying to concentrate more esters-  sending more flavour into our Feni. After all isn’t taste tied very closely to smell?

Those unpleasant musty aromas of the wash are caused by sulphur which isnaturally present in any organic material. Excess of sulphur in the juice needsremoval in the distillation, as it is a one way ticket to hang over city. Andthis is essentially the reason why pot stills are made from copper: The sulphurreacts with the copper walls of the pot still to form an insoluble coppersulphate that is green in colour. With the ester formation and sulphur removed,the distillate is now the robust Feni that we all enjoy during our summer evenings.

Because of the highly complex chemistry of such arich mixture of substances if difficult to understand with absolute certaintywhat actually is going on inside a copper pot still during distillation. Maybewe will never know, but we can truly appreciate the distinctness of a fine Fenibouquet.

Collecting Feni in a launi

Collecting Feni in a launi