Phenols: Peat ppm

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Toxxyc

New and loving it
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Hi guys,

So I've made a few batches of all grain wash recently and distilled it with my crude pressure cooker still. It works. I blended a bunch of these stuff together and stuck them on all kinds of oaks and toasts for a few weeks and 5 weeks later I had a spirit that's actually pretty damn good. Yes it's young, it's green, it's harsh and it's crude, but for a few bucks per bottle and 5 weeks' of time I would call it a "success". So I'm continuing.

Right now I have a wash I made with some corn and malt. Low corn content, just for a bit of flavour. I totally missed the efficiency I was hoping for (still don't know why) so I'm going to be blending it with more malt distillate for some volume. I also have a nice strong wash I made busy fermenting that should give me a few litres of useable new make spirit as well.

But that's beside the point. What I want to ask before I drifted off is this: I've made regular malt washes to date, but my next step is a peated whisky. I'm a big fan of peat, from the low peats to the high ones. So now the high ones are what I'm aiming for. The malts we can get in South Africa is pretty limited, with only a handful of places stocking peated malt. The one thing I noticed as well is how the phenol levels of these malts differ from brand to brand. One brand's malt has "between 5 and 10" ppm, and the other has 15 to 20ppm. So that's a vast difference, but I don't really mind the difference as long as I can concentrate it into the whisky.

So my question: How would I know what ppm I would end up with if I use the different malts? I want to hit high PPM in the final product, but how do I get that and how can I "calculate" if I use, say, 8kgs of 15ppm malt to make a batch of whisky?
 
PPM is a measure of the amount of some solid in a given volume of some medium.

My guess is that in this case it is the amount of peat smoke in a volume of liquid. It might be water or it might be spirit at a standardized alcohol percentage.

You're probably going to have to do some digging and then a bit of math.

Or... you could make a smoke box and bubble peat smoke through your cask strength product until you get the amount of peat character you are looking for.
 
In South Africa getting stuff like proper peat is a mission. I'd rather just use the peatiest malt I can find. I read somewhere that Ardbeg uses peat at around 55ppm to make their whiskies, and they're typically 90+ ppm on the peat phenolic levels. I know it's not the all and everything, but it's a good place to get started. To be honest I'd be happy just hitting 50ppm in the end product, although more would be nicer. I want to make the peatiest stuff I possibly can, and then if it's overwhelming I'll blend it back with a plain malt new make spirit before oaking. I just want to be able to have a good level of peat smoke in the nose, palate and finish.

On the note of "in a volume of liquid", it could make sense, but considering it's used for making beers and stuff as well, I don't know. To boot, distillation concentrates the phenols, so perhaps it's something that someone has tested before?

I would say the ppm refers to a phenolic count per weight of grain. It makes more sense to me.
 
It's one of those horrible non-linear things that depends a lot on age, which distillation cuts you take and all those kinds of things - it's as much art as science. So there is no simple formula to derive whisky ppm from peat ppm, it just depends.

Ppm is just a way to express a fraction in the same way as percent is - but a millionth rather than a hundredth. So if you have a million atoms of iron, or pieces of fruit, or water molecules in a solution, and you have 1 atom of chromium, or 1 banana, or 1 calcium ion, then you can say you have 1ppm of that thing.

In this case the "thing" is molecules of phenol compounds.
 
I completely understand what PPM is and how it works (parts per million). What I'm asking is if there's a way to calculate how much of those phenols will end up in the distillate if I, for example, get a 75% mash efficiency and distill it twice, cutting out only the hearts. I guess not, and I'll have to just buy it, mash it, ferment it, distill it and taste?
 
If you read whisky island, a great book, it has to do with the still, the way the distillate is condensed, lots of things. So, it would depend on your system and process.
 
Ah, so the still does play a good part. I built a very basic pot still from an old pressure cooker and it captures flavours very well (tried it with birdwatcher's sugar wash, my own sugar wash, a rum wash and several all-grain whisky washes now) so I hope that'll help.

Now to wait for the malt to arrive in South Africa...
 
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