Wednesday, March 19, 2008

Scotch fermented over peat, eh...

One of the things that a geek of any discipline loves to sometimes do is get annoyed when they read something that is completely wrong, and then complain about the ignorance to fact on their low-readership blog to make themselves feel smart (or to waste time when they should be doing real work)...
All of that is true of this post I am writing. The geek topic? Distilling. The thing I read that caused me to divert my productivity? An articles that appeared in The Capital Times of Madison, Wisconsin entitled Heres what sets Irish Whiskeys apart.

In particular, this statement by local pub manager and whiskey expert David Drake, quoted from the article:
"Scotch whiskys are fermented over peat fires in open-top casks, which enables the peat smoke to permeate the liquid," says Drake. "Irish whiskeys, most of which are blends, are always distilled in closed containers. This keeps out the flavor of smoke, and a triple-distillation process adds greater smoothness and refinement to Irish whiskeys."
Its unclear weather maybe he was misquoted or if hes just misinformed, but the statement just doesn't make any sense. Lets review the distilling process to see why that is:

1) Malted barley is produced from barley (obviously). Traditionally, in Scotland anyway, the malted barley is dried by heating the air with fires of burning peat moss. The malt retains the highly flavour-active compounds from the burning peat, which will eventually carry through to the final spirit after distillation. In modern production, small amounts of malt are peated in this way, but a lot of malt is dried with gas furnaces.

2) The malted barley is ground up and mixed with hot water in whats called a mash. Just like in brewing, the purpose of the mash is to use the natural enzymatic power of the malt to break down starch to fermentable sugar for yeast to convert to alcohol.

3) Wort produced from the mash is cooled and yeast added, and the fermentation begins. Yeast convert the sugar to alcohol. This is done in large vats (and there are no fired burning under them).

4) After the fermentation, the 'wash' (as it is now called after fermentation) is distilled in pot or column stills depending on what type of product is being produced (malt Scotch is done in double pot stills).

Ok, now back to the problem with the statement. The first problem is that he claims during scotch fermentation peat fires burning under casks add the peaty flavours. That's just not true, you don't burn a fire under a fermentation, that's ridiculous. So, that means that perhaps the author wrote fermentation when he should have written distillation. So the claim in that case would then be that Scotch whisky is distilled using burning peat fires for heat. Unfortunately most distilleries use steam jackets/coils to heat their stills. So no smoke during distillation. Even if the heat was supplied by peat fires to the stills, there would be no permeation into the liquid, as all stills are in fact closed.

So perhaps I'm being a little picky, and I'm unsure if the expert is wrong or if the article author just wrote it wrong... but in any case the only thing I really want to point out is where the peat character comes from in peaty Scotches:
It comes from the malt production, which happens before fermentation, before distillation, and before aging in oak. Not in distillation, not in fermentation, and not in aging.

There were some other false statements in the article, but nothing I'm going to bother writing about... I should probably get back to work...

Cheers!

1 comment:

milan said...

The fella quoted in the article is flat-out wrong. Wrong. It's the barley malt, in the process of being dried prior to the fermentation process, that is exposed to the smoke from burning peat because the kiln in which it is dried permits the mingling of the peat smoke with the drying barley malt. In the type of kiln used for making Irish whiskey, the barley malt is NOT exposed to smoke from burning peat.