What does a Spirit taste/feel like from a vacuum-still vs pot-still

[navenjohnson]

We roto-vape a lot of stuff and I have even told tour participants (right or wrong) that our little roto-vape represents what some might call the "apex of distilling" but I am wondering how correct or incorrect I am. 

Is vacuum the apex of distillation so to speak?

How does "Large scale" vacuum spirit differ from pot still and in what way? 

Am I crazy?.....wait, I already know the answer to this question!

[Thatch]

1 hour ago, navenjohnson said:

Is vacuum the apex of distillation so to speak?

A pretty good discussion from a couple of years ago.

 

[navenjohnson]

Thanks for that, Thatch! 

[Skaalvenn]

We do a lot of R&D with vacuum in our lab. There's a time and place for vacuum distillation, some things taste and smell better when done at low pressure/temperature and some things taste and smell better with traditional distillation methods.

Same goes for just about everything out there. Some flavors are better when directly infused, pressure infused, vacuum infused, vapor distilled, steeped, or combinations of methods. We have a large array of tools for creating, extracting, or manipulating flavors/aromas/textures but sometimes the age old methods are the best choice.

Distilling under vacuum has its advantages and disadvantages from a flavor perspective. Do you or do you not want the changes and chemical reactions that happen in a traditional still for the product you're trying to make?  Is a brick house always better than a timber house? 

[meerkat]

It is hard to add anything to the excellent write-up by Silk City in the earlier thread linked by Thatch. I can only elaborate on why vacuum distillation is different, rather than automatically better.

We know that in distillation the more volatile components find their way to the top of the column, while less volatile components are found lower down. So a highly volatile component like methanol migrates to the top faster than ethanol, while a less volatile component like fusel oil stays nearer the bottom.

The ratio between these volatilities is known as "relative volatility", and relative volatility changes with temperature. So if you distill at a lower temperature the relative volatilities will change and the profile of flavor components in the column will change too. This is not good or bad, unless you are looking for a particular profile.

This is a small effect, and the effect of temperature on degradation reactions and the impact of low pressure on the column diameter requirements (both discussed in detail by Silk City) are generally more important.

[Silk City Distillers]

1) Make a vodka called 6.5 millibar and market it as distilled at the same atmospheric pressure as Mars.  "Filter" it through some crushed up asteroid if you have the money.  

2) Get Elon Musk to retweet.  

3) Profit.

 

[Southernhighlander]

 

 

11 hours ago, Skaalvenn said:

We do a lot of R&D with vacuum in our lab. There's a time and place for vacuum distillation, some things taste and smell better when done at low pressure/temperature and some things taste and smell better with traditional distillation methods.

Same goes for just about everything out there. Some flavors are better when directly infused, pressure infused, vacuum infused, vapor distilled, steeped, or combinations of methods. We have a large array of tools for creating, extracting, or manipulating flavors/aromas/textures but sometimes the age old methods are the best choice.

Distilling under vacuum has its advantages and disadvantages from a flavor perspective. Do you or do you not want the changes and chemical reactions that happen in a traditional still for the product you're trying to make?  Is a brick house always better than a timber house? 

We have a system that gives the best of both worlds: a vacuum still for stripping and a conventional spirit still for the final run.  Our vacuum stripping stills are fast and cost only a little more than our conventional stills.  Our vacuum stills can be fired by a hot water heater, hot water boiler or wood fired hydronic boiler.  If you are in the right area, firing a vacuum still with wood is the most economical way to go.  paul@distillery-equipment.com

 

[navenjohnson]

25 minutes ago, Silk City Distillers said:

1) Make a vodka called 6.5 millibar and market it as distilled at the same atmospheric pressure as Mars.  "Filter" it through some crushed up asteroid if you have the money.  

2) Get Elon Musk to retweet.  

3) Profit.

 

Brilliant! 

 

[Galapadoc]

4 hours ago, Southernhighlander said:

 

 

We have a system that gives the best of both worlds: a vacuum still for stripping and a conventional spirit still for the final run.  Our vacuum stripping stills are fast and cost only a little more than our conventional stills.  Our vacuum stills can be fired by a hot water heater, hot water boiler or wood fired hydronic boiler.  If you are in the right area, firing a vacuum still with wood is the most economical way to go.  paul@distillery-equipment.com

 

Paul, did you get my email about this over the weekend?

[Southernhighlander]

Galapadoc,

I'm currently finishing up Fridays emails.  I saw your email and will answer it shortly.  The problem with a vacuum still at your location is that your cooling water temp is too high.  You would need coolant that is 53F or colder.  Colder would be better, so you will need a chiller if you run a vacuum still.  When you lower the boiling point of ethanol under vacuum you also lower the temperature at which ethanol will condense which means you need colder condenser coolant. 

[JustAndy]

On 5/2/2021 at 11:29 AM, navenjohnson said:

We roto-vape a lot of stuff and I have even told tour participants (right or wrong) that our little roto-vape represents what some might call the "apex of distilling" but I am wondering how correct or incorrect I am. 

Is vacuum the apex of distillation so to speak?

 

If you make whiskey or brandy, plenty of people would say the apex of distillation is in a direct-fired copper pot still. 

[navenjohnson]

26 minutes ago, JustAndy said:

If you make whiskey or brandy, plenty of people would say the apex of distillation is in a direct-fired copper pot still. 

Direct fire on a copper kettle would be about as traditional as one could get, JustAndy. We are a pot-still distillery all the way, but I like the ease, cost, and usability of stainless and steam. 

[Skaalvenn]

11 hours ago, Southernhighlander said:

 

 

We have a system that gives the best of both worlds: a vacuum still for stripping and a conventional spirit still for the final run.  Our vacuum stripping stills are fast and cost only a little more than our conventional stills.  Our vacuum stills can be fired by a hot water heater, hot water boiler or wood fired hydronic boiler.  If you are in the right area, firing a vacuum still with wood is the most economical way to go.  paul@distillery-equipment.com

 

I have one of your regular stills. I appreciate the technical support you gave for what was wrong from the factory, but I'm good on future purchases.