Found some interesting data from a micro-distillery

[oakgriff]

While reading through the web-page of a distillery in my area, I found this spot where they post super detailed information about literally everything in their whiskey making.

https://copperworksdistilling.com/past- ... -releases/" onclick="window.open(this.href);return false;" rel="nofollow

If you click on the "production specs" for any of the releases it'll take you to a pdf with tons of interesting info. One thing I found is that they are consistently getting a higher exit proof than entry proof, meaning that the angels seem to be getting a bit short-changed! Interestingly, this affect does not seem to happen on their ex-sherry casks, such as the Oloroso hogshead in release 11. For release 12, one barrel's entry proof was only 50%! It exited the barrel at almost 58% as well. They seem to be going the reverse direction as most scotch and bourbon. Starting out lower and moving up in abv over time, which no doubt changes the extraction and flavoring significantly.

They also state that they age in a temperature controlled environment at 70F with 50% relative humidity, which I think might cause a lot of that effect. My intuition would be that this might not produce as many beneficial esters during aging, but oh boy, their stuff is off the charts fruity and light and caramel-y.

Take a look at the details, and let me know if you see anything cool there, there's a lot to see! I want to take a look at the tasting notes and see if I can correlate some info in order to reproduce those flavors.

[Windswept]

I think I read somewhere that places with a lower humidity tend to preferentially pull water out of the barrel while aging, while higher humidity places tend to pull out more alcohol. This could be one of the major differences between hot- and cold-country whiskeys, no?

It also looks like they're aging for 2 years (about) so maybe you see a preferential water-loss in early aging, then a preferential alcohol-loss in later years?

Very cool though, and the level of transparency is awesome!

[oakgriff]

I think most of what they have released is around the 2 or 3 year mark. Let me tell ya though, the last thing those whiskies taste like is young, so they are doing something right.

I actually got a chance to talk with the head distillers there a while ago, they came from the beer brewing world, one was the master brewer at red hook for years. I had never hear of any distiller doing a cold-conditioning for their wort, or even fermenting as long as 9 days. If I recall correctly most bourbons and scotches ferment out in just a few days.

[DetroitDIY]

I aged 5 gallons of rum in a 15 gallon barrel for 2 years in a VERY dry basement. My spirit ABV rose double digits (60% in, over 70% out). I'm now putting in my spirits at a lower ABV so they pass trough my target ABV and also pull off different flavors from the woods at the lower strengths (55% in... we'll see what comes out).

[oakgriff]

Do you think that the fullness of the barrel produced some of that effect? How much volume did you lose overall?

[oakgriff]

Ok, I am still interested in this, hopefully others will be too.

I have done some reading on the forums about clearing a wort before stilling, mostly to prevent yeast from being boiled. It seems that there is a semi-consensus here that clearing the mash has pretty much no effect on the final flavor, with some users claiming to have tested two distilled washes side by side, one dirty, one not. They claimed to discern no difference. I think that may have been MichiganCornhusker (spelling?). If you have tried this please let me know what your findings were!

Anyway, I saw that Copperworks was cold crashing their fermented mash, in some cases for over 20 days. I got curious and shot an email off to them asking about this. The master distiller/founder there got back to me within a couple of hours with some awesome info. Jason Parker says:

We find that by leaving the grain, trub, and yeast behind, we get a much cleaner new make whiskey. The new make whiskey has flavors of malt sugars, fruits, and even floral notes, but none of the astringency we'd expect from the grain husks and trub, nor the "meaty" and bitter tastes from the yeast.

Distilling this way is not usual. It yields less alcohol than traditional methods, and takes weeks longer than most distilleries take. But this is how we made beer when we were brewers, so is how we begin all of our products now that we're distillers. And by starting this way, we can make a delicious product that is both distinct and delicious. That's why we have our motto on every bottle "From Great Brewing Comes Great Spirits".

I personally have never cleared the yeast from an AG before distilling. My typical method is to ferment on grain, squeeze the shit outta the lees/spent grain and dump the liquid straight into my boiler. I really do think that this will make a difference, because my new make almost always has some meaty-ness. This usually tends to dissapate after airing out, but if I could avoid that stuff in the first place why wouldn't I? I'm buying a bag of malt today, and am going to try using some finings to clear the mash before distilling this time. I'll let everyone know how it works out in a coupla weeks.

[StillerBoy]

Personally, be a wash or a mash, I always let it settle out or use 2 part clearing agent.. don't like the cleaning that comes with running to quickly after its finished.. some are ok/not bad to run, others puke like hell.. some all grains are ready bad.. so it's a personal thing.. be-careful with all malt, it foams during fermentation, and pukes during stripping big time.. just go easy..

As for the plain sugar wash, I always clear using the 2 part clearing used in wine making.. otherwise, the yeasty smell and taste are there.. want a good neutral from a plain sugar wash, clear it before stripping and stop at the 50% average.. uncle jesse's whiskey I don't use any clearing agent, but let it set out for about 7 - 10 before stripping..

On all grains, I don't use the 2 part, but I do rack and press, then I let sit for about 10 - 15 days to allow for some sediment to settle in a carboy with an air lock..

I have done Tugboat's rye, which he racks off after its finish fermenting, then let it settle under air lock for about six weeks before stripping.. does make for a nice whiskey..

Depending on which finning you use, some work ok, some don't.. letting them settle under air lock (like a secondary fermentation) seem to work the best, at least for all grain..

Mars

[seamusm53]

Exit proof doesn't mean the angels aren't getting their share. Volume has to be measured.

[oakgriff]

I get that, Just meant that the angels weren't getting their usual portion of ethanol in the evaporation. If 15% total volume is lost in 2 barrels, one where proof goes and one where it goes down, the angels get less booze from the one where proof rises.

I'm looking forward to running a more clafied AG mash and seeing how different the flavors are. I have had some trouble with puking in the past, but I would just run slower to combat that, rather than changing my mash at all. I used to just run the day the mash hit 1.000, but i think patience (and some gelatin) will reduce puking and create a better flavor.

[DetroitDIY]

Do you think that the fullness of the barrel produced some of that effect? How much volume did you lose overall?

Only done one barrel (on my 2nd and 3rd now, and haven't snuck into them yet), so I don't have any foundation about your fullness thought.

Don't know how much volume I lost either, as I was taking it off in portions , and wasn't keeping track.

[DetroitDIY]

So I’ve been thinking a bit more about this.

When I would pull the bung off the barrel, there was typically a very noticeable release of pressure from the barrel. So each time, after replacing the bung, the internal barrel pressure would rise. And the barrel had a lot of volume for the liquid to become gaseous (initially 5 gallons in a 15 gallon barrel, and over time decreasing to a gallon or so in a 15 gallon barrel). And I’m thinking of the ideal gas law (PV=nRT), and partial pressures of water and ethanol. And I must admit I am rusty enough with partial pressures that I can’t do anything with that without lots of homework.

But It does seem that if I have 5 gallons in a 15 gallon barrel, then the water / ethanol mixture would evaporate to fill the 10 gallons of air volume in the barrel (partial pressures of air, water vapor, and ethanol vapor). And that I’ve given 15 gallons of surface area to react with for 5 gallons of liquid, so the angles are taking their share at an accelerated rate. More so than if I had a full 15 gallon barrel, and even more than if I had 5 gallons in a 5 gallon barrel… that this promotes a super accelerated rate.

And if the low humidity environment preferentially draws ethanol out of the barrel, then I’m supercharging this water evaporation. I’m expecting that some ethanol evaporation is taking place as well, but proportionally more water than ethanol for the ABV to rise. However, since I didn’t measure the volumes out, I don’t really know how much water or ethanol I lost. And it may be that lost more ethanol in a dry environment than I would have in a humid environment. The only thing I’m truly detecting as I measure the ABV is whether I lost more water or ethanol.

Given a dryer barrel exterior and a corresponding faster migration of wet to dry through the barrel wood wall given the greater wood humidity differential due to the dry exterior air, it seems only reasonable that I should experience faster evaporation in my dry environment. All things trying to reach equilibrium.

So, the more I think about it, I’m very suspicious that I’m losing a good amount of moisture from my barrel, and likely more ethanol than if I were storing my barrel in a humid environment.