Bourbon creating biofuels as a byproduct?

[cowdery]

Ah. Now I see the difference. This is a common misunderstanding that happens when people try to equate bourbon column stills with the grain whiskey stills in Scotland. The stills in Kentucky are much smaller. Some 'products,' if you want to call them that, are vented away at the top of the still, in some set ups, but otherwise nothing is removed except by the process itself. The difference is that the rum, tequila, and vodka stills are much, much bigger and they're removing everything.

This is not strictly a function of through put. An American whiskey distillery will have multiple stills rather than one enormous one. They're trying to craft a taste, not remove all taste.

I get it now, I can see how in an ethanol plant you would produce enough of these what I would call distillation by products to make it worthwhile to capture them.

So, no, for all intents and purposes there is no fractional distillation going on in bourbon production.

[Gillman]

That's it, I think the larger number of plates, spaced closer too in the big towers used to produce grain whisky etc., facilitates taking off all the non-ethanol by these deliberate draws from the plates in the columns. Whereas in the smaller American columns, the separation is achieved just by what is left in distiller's beer as compared to what goes to the doubler. It's more rough and ready, as a pot still is in terms of what it separates in the multiple runs. Further reading has suggested to me that the removal is done, both to reduce the amount of fusel oils in the final spirit and increase output.

Gary