Tuesday, May 29, 2018

Richard Seale: Talks about the Wooden Pot or Vat Still

Richard L. Seale
     Richard Seale is one of the most knowledgeable rum makers in the world.  His personal experience along with all of his research makes him one of the best sources for all things rum and the production of rum.  I have found his discussions to be very well written and very factual.

     I recently posted about those clever Jamaicans and their Cousins process for super high ester rum, today I will write about those clever Guyanese and their Wooden Pot Stills - the VAT STILL.  Today we marvel at the two remaining wooden pot stills but back in the day wooden pot stills, known as VAT stills were numerous in Demerara.  The pot/kettle part of a pot still is unimportant (save for setting the volume) to the character of the pot still.

The Pot/Kettle Part Is Not The Still, It Is Just A Vessel.
Demerara's Double Wooden Pot Still
     In a pot still it is the size and shape of the reflux surface - the surface where the rising vapor has an opportunity to condense - that decides the fundamental nature of a pot still. Reflux (the condensed liquid on the side that falls back) affects the timing of the arrival of the congeners in the final condenser and directly then the ability of the distiller to “select” the spirit he/she wants from the wine being distilled. Generally, large surface area, more atmospheric cooling, more condensation i.e. more reflux.   The material of the refluxing surface is also vital because of the catalytic effect of copper. Copper catalysis reactions which render unpleasant volatile sulfur compounds into non-volatile sulfides which then do not distill over into our rum.

     So the pot/ kettle part plays no role in either critical part of distillation. It does get exposed to the boiling acidic liquid and will eventually wear out and disintegrate making for an expensive replacement. The clever Guyanese figured out that replacing the kettle with readily abundant wood saved money and had no negative affect on the produced rum.
Vat Stills Became The Norm
Today our friends in Guyana promote a positive effect from the wood. Maybe. One thing is for certain, it has no negative effect.  Demerara was also famous for adding the rectifier to their pot stills - that was the subject of an earlier post.