Talk to me about your slow proofing SOPs

[Up&Adam]

we are working through our small format barrels, i have a stock of 15s and 30s full of Bourbon and Single Malt that we will be pulling for the next couple of years until we get into our stock of 53s. i pulled 2x 30s last week that are 2 years old and a little rough around the edges, barrel entry proof was 125 (definitely a contributing factor to the spice level) and they are now sitting at 131.6 proof (no climate control in our warehouse in the South East) I would really like to slowly proof them over the next month or two to bottle strength if the available headspace allows. i keep tare weights on all of my barrels so i assume it will be pretty easy to just use the Cut To Proof function in Whiskey Systems alongside my floor scale to approximately bring them down to human strength. How is everyone going about this? how much proof are you dropping per day/week/month? how are you tracking it and what does your process look like? Many thanks in advance for your time and information.

[SCLabGuy]

Here's a video on slow proofing from one of the distilleries (maybe THE distillery) that brought the slow proofing concept to light (brandy makers have been slow proofing for eons).  https://www.youtube.com/watch?v=mFUdKxMN3BU

You have the right idea to cut by weight.  Personally I like to circulate the whiskey in a tote with a small-ish pump (just pump over itself) while a 1/4" ID R/O water supply flows into the tank.  That takes minutes/hours instead of days.  Proponents of slow proofing will tell you that fast cuts lead to cloudy whiskey and/or saponification, and also that the heat increase from cutting causes volatile aromas to be lost to the atmosphere.  I think there's something to the first point and not much to the second point, unless your spirit and/or water are too warm to begin with.

If you have multiple similar barrels, why not proof one down slowly (drip feed maybe?) and the other quickly and see if you can pick a difference in a triangle test.  If you can't, maybe it's not worth the trouble.

[Up&Adam]

Thank you for the reply, I think I will follow your advice and do a triangle test on them. I have nothing but time while were waiting on shipment and installation of our new still. 

[Kindred Spirits]

Cutting and blending batches of spirits is one of my favorite things to do.

It is amazing how many distinct flavor profiles you can get from a mixture of barrels, even if they were from the same batch, just in different sized barrels.

Those rough edges you talk about may pair nicely with another barrel to create a great spirit.

If you would like any help with this please reach out. 

[kleclerc77]

We reduce the proof slowly over 4-8 weeks as well. We make larger proof reductions initially, while slowing down the proof reduction once nearing the 100 proof mark. ~One proof degree per reduction from then on. Some suggest doing small reductions all the way, which probably wouldn't hurt. An important aspect of water additions is good agitation. We mix with a paddle while water is being added, and multiple times per day for the following week or so to encourage proper incorporation. It may be hard to get proper agitation/mixing if you are proofing in the barrel.

[Mr_Whiskey]

Huge advocate here of slow proof reduction. I just add about 250ml of water to each barrel every few days till the spirit in the barrel is close to bottling strength. This process typically takes 6 to 10 weeks

[PeteB]

I have almost always done proofing in one hit. Never had a problem with saponification, but I think I might do a test. Split one barrel into 2 diluting tanks to make sure any barrel differences are not obscuring the result..

[PeteB]

Most of the slow proofing I have done is in the barrels, replacing some of the angels share with water. Up&Adam mentioned using tare weight of the barrel in calculating how much water to add. That won't be accurate because there can be several Kg of spirit soaked into the wood. The abv in my barrels increases with time, the whisky that has soaked into the wood is significantly higher than what was in the barrel. I have tested the whisky that seeps back into the barrel a few weeks after it is emptied and found it can be 10% higher than the bulk content was. I assume that in climates where proof decreases with time, that seepage would be lower ABV. If I cut to a certain proof and leave the whisky in the barrel the proof goes up quite quickly in just a few week. 

[Up&Adam]

On 7/1/2022 at 10:30 PM, Mr_Whiskey said:

Huge advocate here of slow proof reduction. I just add about 250ml of water to each barrel every few days till the spirit in the barrel is close to bottling strength. This process typically takes 6 to 10 weeks

This brings up a question that I've seen discussed here in the past but never saw a definitive answer. first off, are you starting to proof before a barrel reaches its intended age statement? if not it shouldn't really make a difference to the TTB, If so does the addition of water to a barrel change the age statement? would your aging stop as soon as water is added or is it fair game as long as the spirit doesnt leave the barrel as its being slowly proofed? people certainly have opinions but i have not seen a CFR regarding this specifically.

[Up&Adam]

On 6/30/2022 at 12:19 PM, Kindred Spirits said:

Cutting and blending batches of spirits is one of my favorite things to do.

It is amazing how many distinct flavor profiles you can get from a mixture of barrels, even if they were from the same batch, just in different sized barrels.

Those rough edges you talk about may pair nicely with another barrel to create a great spirit.

If you would like any help with this please reach out. 

i will certainly be reaching out later this year after a few single barrel releases, i am interested in what your process looks like.

[Kindred Spirits]

8 minutes ago, Up&Adam said:

i will certainly be reaching out later this year after a few single barrel releases, i am interested in what your process looks like.

Sounds like a plan, I look forward to hearing from you.

[Pour Decisions]

On 7/6/2022 at 12:27 PM, Up&Adam said:

This brings up a question that I've seen discussed here in the past but never saw a definitive answer. first off, are you starting to proof before a barrel reaches its intended age statement? if not it shouldn't really make a difference to the TTB, If so does the addition of water to a barrel change the age statement? would your aging stop as soon as water is added or is it fair game as long as the spirit doesnt leave the barrel as its being slowly proofed? people certainly have opinions but i have not seen a CFR regarding this specifically.

If you find anything definitive here, I'm interested in hearing it!