Gin run using a LM reflux still in "pot still mode"?

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sphaleron
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Gin run using a LM reflux still in "pot still mode"?

Post by sphaleron »

Hey guys,

Following some excellent advice from StillerBoy and others I have decided to build a modular concentric reflux column as my next still. The main attraction of the modular build is to allow me to operate in "pot still mode" (short column, no packing, needle valve fully open) for stripping runs, and in "reflux mode" (tall column, packing, needle valve controlling reflux ratio) for spirit runs. I see it as a compact, easy to store, "does everything" still design.

However, I am primarily interested in making gin, both macerated recipes and vapour infusion recipes. Can I use the concentric LM still in "pot still mode" for a gin run? For vapour infusion recipes there is previously stated concern that reflux drips will wet the botanicals and potentially block the column. Could this happen when operating in "pot still mode"?
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Re: Gin run using a LM reflux still in "pot still mode"?

Post by DrMalt »

Should be able to make some fine gin in LM pot still mode. I do it on my Boka without the column attached. Best gin I ever had following Odin's Tried and True Method.
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Re: Gin run using a LM reflux still in "pot still mode"?

Post by greggn »

> I have decided to build a modular concentric reflux column as my next still.

What was your "first still" ? Depending on its design you may find it easier to modify that one to be a dedicated, gin-only column.
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Re: Gin run using a LM reflux still in "pot still mode"?

Post by still_stirrin »

greggn wrote:> I have decided to build a modular concentric reflux column as my next still.

What was your "first still" ? Depending on its design you may find it easier to modify that one to be a dedicated, gin-only column.
I’m thinking this one: http://homedistiller.org/forum/viewtopi ... 5#p7499448

Plenty of opportunity there. Hopefully the “science” isn’t tripping him up. :o
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sphaleron
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Re: Gin run using a LM reflux still in "pot still mode"?

Post by sphaleron »

still_stirrin wrote:
greggn wrote:> I have decided to build a modular concentric reflux column as my next still.

What was your "first still" ? Depending on its design you may find it easier to modify that one to be a dedicated, gin-only column.
I’m thinking this one: http://homedistiller.org/forum/viewtopi ... 5#p7499448

Plenty of opportunity there. Hopefully the “science” isn’t tripping him up. :o
ss
That's the one. The pot still isn't up to the job of making the neutral base for the gin, hence the need for a reflux column. The reason i ask is because I'm tempted to salvage some pipe from this redundant pot still if the new modular concentric can be used for a gin run.
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Re: Gin run using a LM reflux still in "pot still mode"?

Post by Odin »

I make gin in my LM in potstill mode all the time. And so do my customers, with great success.

If you use the right packing (say spp or hcp with around 90% open space), the impact of that packing on the gas flow is relatively minimal. Only slightly higher (yes, like 10%), when compared to a LM column without packing.

Okay, now stay with me. You do not need to unpack the column (given you pack with very open and as advanced as possible column packing and that it be chemically inert). Okay, you may have guessed that from the above alinea. But in fact you do not even need to add a smaller/shorter column. Just leave the big, tall normal column on. The bigger, taller column that you may normally use to create your neutral with actually has a few benefits.

First of all it is less work. No need to swap columns. Secondly, the taller column will see a bit more inefficiencies in potstill mode (where you open the needle-valve fully not to create reflux). Higher column equals slightly higher energy losses, net to gross, reducing vapor speeds a bit. Probably very close to the 10% in vapor speeds you gained by not unpaking ... Meaning overall performance may equal your shorter, non-packed column.

Then there is a final benefit you may want to try out. I use it to great success. And - again - so do my customers. Stabilize at the beginning of the gin run. It will concentrate any residual small heads faction as well as the overconcentrated, very rancid first juniper oils perfectly. Say you leave the normal packed column on and you now stabilize for 15 minutes. Then (and only then) open up the needle-valve quickly and completely. You toss the first little bit (away with some remaining heads and rancid first juniper oil), and you get very nice very fruity transition from 95%+ to say 80% for the beginning of the rest of the run (slowly dropping of).

I use this same technique on whisky making. Yesterday I did a run with my 2000 liter rig. Okay, too big for here, but you know that I build stills professionally and I just want to make the example clear. That's 2000 liters of around 25% low wines and fresh wash combined. Because it is a bigger rig, I stabilize for 30 minutes. And I only draw off a heads faction of 1.5 liters. This saves me an amazing amount of hearts, by not "spending" good ethanol to heads, and it creates a nice, controlled fruity first part of the heasrts run that further increases the taste complexity of that whisky.

Regards, Odin.
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sphaleron
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Re: Gin run using a LM reflux still in "pot still mode"?

Post by sphaleron »

Odin wrote: Then there is a final benefit you may want to try out. I use it to great success. And - again - so do my customers. Stabilize at the beginning of the gin run. It will concentrate any residual small heads faction as well as the overconcentrated, very rancid first juniper oils perfectly. Say you leave the normal packed column on and you now stabilize for 15 minutes. Then (and only then) open up the needle-valve quickly and completely. You toss the first little bit (away with some remaining heads and rancid first juniper oil), and you get very nice very fruity transition from 95%+ to say 80% for the beginning of the rest of the run (slowly dropping of).
Thanks very much Odin, that's really useful information. In your "easy gin" recipe you recommend tossing the first 10ml. is that due to the rancid juniper oils you describe? If I was to follow your method about for my concentric reflux still would you still recommend tossing the first 10ml, or the volume of the concentric collection cup which is about 50ml?
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Re: Gin run using a LM reflux still in "pot still mode"?

Post by Odin »

Stabilizing makes the head cut smaller.

Odin.
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