Acidic tails

Distillation methods and improvements.

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trbig67
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Re: Acidic tails

Post by trbig67 »

Never mind! Saw in your answer! " De-misting:...meaning that if a spirit is clouding when diluting to 40%"
zapata
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Re: Acidic tails

Post by zapata »

Well a true demisting test is actually at like 46% OR so I think. But it's a strange indirect test that really only applies to industry. It's strangely used to determine the headcut, but it's tails that cloud, so what its really testing is when enough heads have run off to clean the last runs tails out of the condenser. And at that it is even less precise than making cuts by temps and only tests for certain tails. But the take away is when the big boys say a run never passed demisting what they mean is tails were present throughout.

But don't get too hung up on cloudiness, or that certain feints are called oils etc. Heres a mathy example that isnt perfect, so just nod at the parts where Im kinda waving my hand around. The water and alcohol math is very realistic, the tails not so much.

Imagine 2 mixtures, same total volume (a boiler full), same ratio of ethanol:tails. Basically mixture 2 is just diluted.
Mixture 1: 1 million units ethanol, 1 million units water, 1,000 units "tails". (50%abv)
Mixture 2: 540,000 units ethanol, 1.46 million units water, 540 units "tails". (27%abv)
(Yes, I know mix 2 is short 460 units out of 2 million+, I'm blaming it on you, you spilled a drop)

Run both these distillations down to 20% etoh. And just assume that the bulk of the tails won't distill over yet. (I'm waving my hand here) What's still in the boiler when you are collecting down to 20%?
In a real pot still it would be:
Mix 1: 13,000 units ethanol 550,000 units water 1,000 tails
Mix 2: 25,000 units ethanol 1,014,000 units water 540 tails
Both at 2.4%abv

Now, if you are still running, mix 2 has twice as much water between the bulk of the tails and your condenser. AND theres only half as many tails anyway because they were diluted with the alcohol. The tails in mixture 2 have a much steeper curve to climb to get to that condenser.
Another way to look at it is mixture 1 boiler has 17.7 PPM tails in it. Mixture 2 boiler has 5.1 PPM tails. We didn't even half the abv (50% to 27%), but tails concentration is reduced by 2/3rds. Reduced concentration is reduced partial pressure is fewer tails distilling at any point in the run.
The tails are made up numbers and units. But the ratios and principles will work the same. Virtually identical math will apply at any point in any run, and apply fairly well even dealing with non-ideal complex mixtures. I'm sure with another hour to waste I could even model a scenario where I account for tails so concentrated they are bleeding into hearts, but I'll leave that up to you to actually try it.

Yeah, but in this scenario, we diluted the shit outta the alcohol, which is what we're trying to make right? Didn't we undo all our hard work diluting our precious booze?
Well, mix 1 would have made product at 68.7% while mix 2 would have been at 53.5% abv. How high and do you want anyway and why? And those numbers were collecting all the way down to 20% which is probably unrealistically low for a 2nd distillation out of 3 when dealing with feints of feints (already trash to most people).

I am surprised that your tails of tails didn't have an oil sheen to them, I guess it does get absorbed somewhere along the way. But what I'm trying to get across here is that dilution dilutes and supresses tails collection regardless of hydro separation misting or clouding, and not at the expense of useful final abv. Also, if it is your theory that it's acids vs my theory it's fusels, it'll work the same way just sub in the word carboxyllic acid instead of tails.

I dunno, maybe I'm wrong. Maybe it really is just heads and bad cuts! :esurprised: But you could give it a shot. If you really don't have much heads in there, just dilute them and run, dilute and run. Your still makes crazy high abv, should be pretty easy to end up at least strong enough to carbon filter. See if it doesnt shift that burn down away from the heads and into tails.
trbig67
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Re: Acidic tails

Post by trbig67 »

zapata,

I thank you for your posts. You've used facts and took a lot of your time for discussion, including several things that were over my head a bit, but what you didn't do is fall back on the "Because it's always been done that way!" The only thing I've ever heard and read about distilling stuff higher than 50% ABV is the " Cause it's dangerous and you'll blow yerself up!" and I've never understood that part. I know people that distill gasoline. Much more volatile than what we're dealing with. But you've come along and explained there is far more to it than that. Now the question is... at what percent to pot? The literature you posted says no more than 30% Most everything I've read says just get it below 50%.

While I am about quality over quantity, I do have to account in for the time I have to do this hobby. A good percentage of the time involved is simply waiting for the pot to heat up and start collecting. On days I have time, I can cut this down significantly by having the next batch slowly heating in another pot and get it up to 140-150f or so before the run is done, but there's a lot of days I only have time for a single run. Then you're talking about more runs to do the same volume of product. BUT... I have learned much from you of the "why". I will try some of these tails first at a 30% ABV rate and report back. It may help tremendously, and it may be you were correct. The tails of a tails run ain't worth keeping! lol. Then I'll try running some of my final run at 30% and see what kind, if any, taste differences. I just need to make sure I reach 145 proof for the final product, so may have top adjust the beginning abv. Many, many of the people I have talked to say to oak at 145 proof. (Bourbon casks at 125, but I don't have the number of years to wait) Too low and you don't get all the flavors from the wood. Too high and it acts like a solvent and you get lots of bad flavors. I write with a sharpie on my mason jar lids. Use a paper towel dipped in the 172 proof stuff and the sharpie wipes off with ease. 145 proof takes a bit of scrubbing. 100 proof won't really take it off much at all. I know, not a scientific test of any kind, but it kind of goes along with what hey were saying.

Anyway, thank you again. I don't have the proper equipment to test the acidity levels of things and don't know the point at which mucous membranes begin to feel a burn, so at this point, whether it is an alcohol or acidic burn is simply guessing. Either way, greatly increasing the water will raise up the PH of an acid as well as dilute the bad alcohols, so the same answer would apply to both. No need in baking soda or such like my original thought direction was to go.
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HDNB
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Re: Acidic tails

Post by HDNB »

Great write ups and discussion on smearing.

I'd reiterate the high rye. I have done tons of rye in the last 2 years. (90% rye grain 10% ryemalt) down to (45% other adjunct grains and 55%) malt rye.

My first runs on 2 plates were failing demisting and were over the top strong in flavour and mouth burn. I was only able to get 100% rye palatable with 4x distillation. It still has a strong flavour and a black pepper spice...but it finally passed demisting at 44.4%

so the smearing problem for me was equipment related, using a bubble plate and the column and kettle was insulated on top.

removing the bubble plate took care of 75% of the smearing. removing insulation from the kettle top solved the other 25% of the problem. Using 2 sieve plates there is no more problems with cloudy spirit at all even down into the teens, never mind 46% (46% is where lipids start to clump up and become visible apparently.)

however, even though i can now strip and run a spirit charge (usually at 38% sometimes lower) and have no problem with smearing, I'm still getting a very robust flavour and still getting rye black pepper finish (a bit of a burn) on the more recent runs at 55% rye

my first 4x distilled 100% ryes are oaked at about 18-20 months. they are smoothing nicely but they still have a black pepper note
I finally quit drinking for good.

now i drink for evil.
trbig67
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Re: Acidic tails

Post by trbig67 »

While thinking about things after I post. ( I do this a lot in life where I think AFTER I've opened my mouth... but I digress) Zapata had asked about anyone knowing if the old-timers did things with the tails and feints. I've read several places of when they used thumper kegs, they use these feints in there, but I don't know what they do with the thumper keg contents after the run? Kept for next use or dumped/fed to the fire? I know of one distillery fairly close that uses a big pot still and uses a thumper keg with feints in it, but I've never asked if they get replaced each run. Nothing specifically that I've seen/read on the re-running of just the tails though.

Then that got me thinking about all of this, "Distill at less than 30% or 50%" stuff. If running a thumper keg, what you are doing is basically distilling twice, so the thumper keg is actually being fed high proof stuff for a 2nd distillation. What's the difference between this vs a person just dumping 100% stripper run he's collected into the pot for the 2nd run who doesn't use the thumper keg? Column stills same thing. Each plate is basically feeding the next plate a higher proof, effectively distilling higher and higher proof stuff. What am I missing?

HDNB, your comment interests me. I'd always been against the column stills for two reasons. Cost, and that they strip nearly all the flavor away. Looks like now it comes down to simply me being a tightwad? lol.
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HDNB
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Re: Acidic tails

Post by HDNB »

trbig67 wrote: HDNB, your comment interests me. I'd always been against the column stills for two reasons. Cost, and that they strip nearly all the flavor away. Looks like now it comes down to simply me being a tightwad? lol.
there's lots of flavour if you don't reflux the shit out of it (maybe even if you do, i have never tried)

i'm a pot stiller at heart. I pissed and moaned about the plater for many runs trying to figure it out. now that the bugs are out i like it's ability to compress the fores and tails cut, leaving a longer more stable cut for hearts. (using a wee bit of reflux to take off at my preferred abv steadily)
in reality i run as a pot and use the deflag as tool. its not the whole deal trying to run off azeo by any stretch.
i'd just caution to do lots of research on the plates...i really had smearing problems on bubble plates with multiple downcomers as they trap and hold (in my experience) lots of tail oils that carry over thru the whole run.

i don't want to drag off topic though, so sorry OP, the acidic tail discussion has been excellent here and my only point was rye pepper flavour is powerful.
I'm really interested to dig into the PH of my fractions to learn more about the topic!
I finally quit drinking for good.

now i drink for evil.
Bagasso
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Re: Acidic tails

Post by Bagasso »

trbig67 wrote:Then that got me thinking about all of this, "Distill at less than 30% or 50%" stuff...What am I missing?
The less than 30% and 50% stuff is for different reasons.

The 50%, as has already been posted, is for safety reasons and you are correct in pointing out that the vapor is over 50% but the reason this safety precaution is used is in the event of a boil over. So while vapor/leak is one problem, high %/boil over is another so filling the boiler with less than 50% eliminates one potential danger, making it safer, not free of danger. Basically removing one thing to worry about.

The 30% stuff has to do with separation of the different compounds. This graph shows how ABV affects the volatility of congeners relative to ethanol.
Congenor ethanol volatility.jpg
I am, of course, also interested in the main topic of the thread and I will be running and taking some readings and posting what I find later tonight.
trbig67
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Re: Acidic tails

Post by trbig67 »

The 50%, as has already been posted, is for safety reasons and you are correct in pointing out that the vapor is over 50% but the reason this safety precaution is used is in the event of a boil over. So while vapor/leak is one problem, high %/boil over is another so filling the boiler with less than 50% eliminates one potential danger, making it safer, not free of danger. Basically removing one thing to worry about.
Sorry, but have you ever watched a cooking show? Ever seen them add wine to a pan? Ever seen the huge flames they get off of that? That's at 8-12% alcohol. Diluting it down because of worry of boil over is not a legit reason. Hot alcohol makes a lot of fumes and if allowed to get out of your pot at whatever proof, you are in danger of a large fire. 90% or 9%. Doesn't matter. The fumes are what burn, not the liquid, and heating it creates alcohol fumes. I'm not trying to be an ass, just stating the the safety issue many use as the reason for doing this doesn't make any sense scientifically. Just because at room temperature, you can light 100 proof but not 80, and use that as your reasoning, it means nothing when you heat it up. As I stated, even the 100 proof, stick it in the freezer a while and then try to light it. I use 172 proof in my alcohol stoves and in cold weather, I have to hold one of those windproof lighters against the surface for quite a while to get a little bit heated up enough so that I can get a flicker of a flame on top. When it's warm out, I have to stand back to light it and generally lose some hair on my knuckles. There does seem to be a reason chemically though at the cellular level to diluting with water. But just for safety reasons doesn't pan out. (Pun intended)
I am, of course, also interested in the main topic of the thread and I will be running and taking some readings and posting what I find later tonight.

I've been discussing things with zapata, and the easiest fix for the acidic tails (Besides throwing them away) is by adding your saved tails in with your stripper run collections. The stripper run would be more alkaline than the tails of the tails,etc..., evening out the acidic properties. At the percentage of tails I would add, @ 1 gallon to 5 gallons stripper run, I still end up with a surplus of tails. So if doing a run of just tails, if you dilute them back down with water before running, as the data zapata posted shows, a lot of the unwanted properties would stay in the pot bound to the water molecules, as well as the fact that the water is going to raise the PH back up considerably. I don't know if a strictly tails run would give you any drinkable hearts to speak of, but it would concentrate and clean up what you have and then that could be added to a future stripper run without such a harsh tails taste/smell. If the burn I felt on my lips/tongue were from bad alcohols as was suggested, diluting with water helps leave those behind as well. So whichever the cause, the answer seems the same.
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Re: Acidic tails

Post by Bagasso »

trbig67 wrote:Diluting it down because of worry of boil over is not a legit reason.
Honestly, I agree with you but I was just repeating it to differentiate it from the 30% idea which has to do with volatility of the boiler charge and is also the basis for hydroseparation.
I've been discussing things with zapata, and the easiest fix for the acidic tails (Besides throwing them away) is by adding your saved tails in with your stripper run collections.
Well here are some numbers. I did a 1.5L (teakettle for a boiler) run of 13% wash caught in 1 and 2 at 40ml portions, 3,4,5 100ml and number 6 going until the thermometer hit 100°C
The wash had a pH of 4.54.

Jar...pH
1.....5.00
2.....5.54
3.....5.43
4.....5.28
5.....4.69
6.....4.37

So, if by stripper run you mean fresh wash at 4.54 with tails at pH>5, there is no way you are going to avoid acidic properties.

Now, one problem I see is that you seem to be under the impression that the low pH is what makes tails tailsy but if you look at my numbers you will see that jar 1 fores/heads is also acidic. But the acid in either fraction isn't what makes them heads or tails.

ETA: Just to be thorough, the backset had a pH of 3.93.

I would also like to add that I meant to measure the all the jars combined but I forgot and treated them with something so that I didn't get a chance. For whatever it is worth, after treating and measuring they read 7.04 but they were still tailsy.
Last edited by Bagasso on Tue Feb 13, 2018 11:29 am, edited 1 time in total.
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Yummyrum
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Re: Acidic tails

Post by Yummyrum »

Thanks for posting that bagasso . :thumbup:

Way back in the third post of this topic I showed a similar thing that heads were as acidic as tails . But interestingly your middle jars are almost as acidic whereas my reflux stilled nutral hearts showed up close to pH 7 . Perhaps the smearing in the strip run made all your jars acidic . :|

As I also mentioned way back n the third post , distilling water will also show up at arond pH 5 due to the CO 2 that the distilate absorbs from the air . Now how can water be acidic :wink:

I know your a chemist guy Bagasso so hopefully you can add somethng to this topic
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Re: Acidic tails

Post by Bagasso »

Yummyrum wrote:Way back in the third post of this topic I showed a similar thing that heads were as acidic as tails . But interestingly your middle jars are almost as acidic whereas my reflux stilled nutral hearts showed up close to pH 7 . Perhaps the smearing in the strip run made all your jars acidic . :|
Sure, tiny boiler and 1kw hotplate is a sure bet for smearing. The interesting bit is that a bell curve was still seen in my numbers which matched your own results; low pH in heads, higher in the middle and then lowering again in tails.

I am mainly interested in just seeing if there is something to it. I guess it would be cool if you could get the pH for a recipe and use that to help guide cuts but I'm guessing that pH is just like temp or ABV, it isn't really enough info about what is coming out of the condenser. Maybe for an often repeated recipe
As I also mentioned way back n the third post , distilling water will also show up at arond pH 5 due to the CO 2 that the distilate absorbs from the air . Now how can water be acidic :wink:
I guess the answer is, it depends what dissolves in it, like hard water being alkaline.

One thing I didn't mention was that I was hoping to measure on the fly but the pH kept dropping even after the jars had been filled so I had to let them sit for about half an hour; so I wasn't sitting there watching the numbers drop a bit every 10 or 15 seconds. It made me think of your post talking about pulling co2 from the air.

Also, what I think the OP might be getting wrong is associating pH to burn because things like orange juice and sodas have a pH between 3 and 4 and there is no burn associated with them. At least nothing that I think compares to hot distillate.
I know your a chemist guy Bagasso so hopefully you can add somethng to this topic
Well, I play one on the interwebz.
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Re: Acidic tails

Post by J0hnni3 »

I would side with those advocating the lower abv. I understand the theory you’re referencing when you mention flambé, however there really is a safety factor to the liquid being below 40%. I’ve personally been saved by it. In my early days, I fortunately was following the safety protocols by rote, even though I didn’t understand them all. I popped the top on a run, and suffered a significant release of vapor and also a significant liquid boil over with a direct fire still.

I was saved by the fact that the liquid put the fire out when under 40%, giving me enough time to shut everything off and dash for the ventilation switch to clear the haze that was now hovering at the ceiling.

You’re right that people can and do operate equipment with higher abv, and that lower abv isn’t a guarantee of safety, however it does represent one of multiple ways we can mitigate risk. It’s good practice to stack the deck with as many of those as possible.
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