Why is lower % alcohol wash better? Congeners?

[Voddy]

I'm sorry if this has come up before, but I haven't seen anything to answer my query:

I accept the given wisdom that a wash at 10-12% is better than a higher 20+% turbo alcohol wash for producing a better vodka. But why? What is the science behind it? Is it that more co(n)geners are formed at higher %ages?

Thanks!

[Cherry Yidaki]

I like this question. Waiting with interest for answers. My as-yet limited reading suggests that the more aggressive/high ABV%-producing yeasts also punch out lots of unpleasant flavors that are difficult to polish away. No doubt there are a myriad other reasons that this fine fellowship of feckful fermenteers will follow-up on.

I have a question along these lines as well: I've read lower temperature/slower fermenting will often produce "cleaner" washes, i.e. fewer bad flavors. I think I saw somewhere that they'll often finish with a higher ABV% as well. If that is so, why not go for the higher ABV%, cleaner, low temp ferment? Or are my facts and or logic processes flawed?

[John51]

I think the slower and cooler ferments don't give that much of an abv% boost. A couple of % maybe, not enough to effect the quality of the run ime. I haven't noticed much difference between the same washes done in summer or winter. Different story during a heatwave with an unsuitable yeast though, stuff fusils, they hurt.

afaik, the different alcohols are easier to separate when at a lower strength.

[chill]

Higher ABV stresses the yeast and makes them produce off flavours. I don't know if these are chemically esters or fusel oils or what.

[Voddy]

afaik, the different alcohols are easier to separate when at a lower strength.

I don't understand why.

[Cherry Yidaki]

So.... if your washes are consistently producing 12-14% - would reccomend reducing the amount of sugar in your recipe? Or a different yeast?

[Myles]

Part of this whole question is related to the point that this recomendation is usually applicable to pot stills. So there is actually a second part to it.
With a pot still you really need to have the boiler charge for the spirit run below 30% ABV.
Now given this factor, the low ABV wash is preferred because the strip run gives you the correct ABV low wines. Start with too high an ABV fermentation and you need to dilute the low wines - this ALSO dilutes the flavour. On a pot still this is often a bad thing.

[Cherry Yidaki]

Thank you kindly, Mr Myles. That gives me a good "why" a lower ABV wash is better for my air still; can you give me some "how" tips? Or should I just go ahead and strip whatever comes about, then be sure to dilute it before any spirit runs?

And just for clarification, assuming you do a triple (or more) distill, do you dilute back to 30% for each run - or only strip #1?

[Voddy]

for what it's worth - with my current knowledge - I do a 'strip' (ie higher temp) first run and then dilute 3:1 water:alcohol for a calmer, slower-paced run at around 53C taking out the heads, etc.

[Easydrinker]

I'm sure someone will jump in and correct me if I am reading this thread wrong,just trying to help,and I don't mind correction.
First it seems Voddy is running a reflux still,of which I have no experience,and Cherry an air still of which I do.
So advice aimed at Cherry;
You have a finished wash,you strip it.
If the wash has a high alcohol content,and you do not like the product after the strip and however many spirit runs,try less sugar in the next one.
And diluting to 30% for any spirit run is the way to go,first or second.
I think all of us have tried to see just how high a % we can obtain,by not diluting,85% seems to be the limit with an air still.Should you try this,don't leave the room,shed,whatever while the gizmo is running.And it really wont taste any better than the distillate of a wash run at 30%
Myles answer is maybe evident to a seasoned distiller,maybe not to a newcomer.And does imply the desire to carry flavour through to the distillate,-if you are shooting for a neutral with a pot still,and particularly an air still,throw as much dilutent in as you wish
Somewhere on this forum I seem to recall a triple distillation recipe,oddly enough,maybe for triple sec,but really,even with an air still,two is enough.
IMHO.
Robert.

[Cherry Yidaki]

Very much appreciated, EasyDrinker. My potential for producing palatable potables improves by leaps and pirouettes of pudendum-pleasuring proportion with every perspicacious, yet pithy, epistle.

You're a pot still prince and prime purveyor of epicurean palliatives. I hate to have my praise and paeans peter out prematurely, but I really have to pee, for some reason.

Which reminds me of a favorite joke, before I sprint away:

What's the difference between pea green paint and the cha-cha?

Answer: You can learn to cha-cha in ten, easy lessons...

*penguin sprinting toward the potty*

[Myles]

For the pot still users having a boiler charge higher than 30% leads to flavour problems. The tails are soluble in higher proof ethanol and tend to be smeared all the way through the run.
For reflux users a boiler charge of 40% is OK. Any higher and you really should be using an indirectly heated boiler.

If I wish vodka to drink it is tripple distilled in the pot still, diluted to about 25% for each charge and run slow. It still has a slight flavour so is not neutral. I make that on a reflux column, but only use it as a feedstock for gin and other infused products. I dont actually drink neutral because I like my vodka to have residual flavour.

[Cherry Yidaki]

The panegyric above applies to you as well, my good preceptor.

I feel like another candle gets lit, revealing more of the target for me, each time one of you "wise elders" is kind enough to pass along some of your experience and knowledge.

I am honing my skills and aiming for that bulls eye. I'll have something righteous good to celebrate with when I hit it, too! Thanks!

[John51]

Here's my theory:

With a higher %abv wash, or a higher wattage heating element, it follows that more vapour is produced. The vapour being a mix of different alcohols and water.

Not all vapour gets to the condensor, some vapour condenses and the liquid drains back to the wash. A sort of reflux action and you can see the thinking behind the Alembic design and Scottish whisky stills in that they want a bit more vapour to condense and return to the wash than a regular pot still.

While there are still lower boiling point alcohols in the vapour, water and the alcohols with higher boiling points are the most likely to return to the wash. That rate of return is limited by the design of the still. Once that limit is reached, more water and higher boiling point alcohol gets to the condensor, aka smearing.

[Voddy]

I'm reading all the posts; just taking a little time to understand them all fully - as I am sure others are, too.

Thanks for chipping in, all.