Yeast... part two

For officers only! Relevent history and facts about the growing, harvesting, fermentation, distillation and aging of Cane Spirits. Master this section and you master rum. Otherwise just masterbate...
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Capn Jimbo
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Yeast... part two

Post by Capn Jimbo »

There's a fungus amongus...


This part will be a slightly idiotic summary of just what yeast is or isn't, and how it works, or doesn't. Get that? Or not?

Here's the deal. The Saccharomyces family of yeasts comes from the Greek: saccharo - sugar, and myces - fungus. The Greeks first noticed this fungus as the thin whitish coating or film on dark grapes. Later they came to realize the importance of this "sugar fungus" in fermenting Greek wine.

This fungus is a single cell, which when active in the presence of a good growth environment can feed on sugar. That enviroment may or may not require oxygen, but will require sugar, nitrogen, phosphorus, sulfur and some minerals like magnesium, iron, calcium, and zinc. In the right conditions the yeast fungus cells can multiply very rapidly, often by budding (a "bud", or baby cell emerges and breaks off), and the chromosomes break off.

Watching a ferment is an amazing, almost primeval experience, like a pit of boiling lava. The yeast is added to a nice yummy rum sugar wash, and the multi-millions of the sugar fungus cells feed voraciously and reproduce until enough sugar is converted to alcohol that the process comes to an end.


Are you a top, or are you a bottom?

Other names for Saccaromyces (S. cerevisiae) include "brewer's or baker's yeast", "ale yeast", "top fermenting yeast" or "budding yeast". While some bourbon and whisky distillers are fairly advanced in their use of yeast, the real professionals in the use of yeast are the beermakers, particularly those involved in micro or the huge homebrewing groups.

These beer fanatics are well, fanatical about trying and developing untold, tens of thousands of complicated recipes that manipulate the ferementation via multiple sources of sugar, temperature, multi-stage fermentations and many, many more variables. The spirits distillation industry could learn much from them.

Especially rogue rum. As an example "ale yeasts" (which ferment near the surface of the wash) require higher temperatures than "lager yeasts" (bottom fermenters which work at colder temperatures) - the ale yeasts tend to produce noticeably more fruity esters (much appreciated in most spirits).

In closing, yeast is perhaps one of the most studied organisms in our world - this research has many important applications far beyond the fermentation of beer, wine and spirits.

Stay tuned...
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