Rectify GNS before making Gin?!

[tl5612]

Hi

I have come across a couple of micro-distillers that make gin with GNS, but before they use this bought-in GNS to make their gin, they will rectify it in a column still (making cuts of heads/tails) first to 'improve' it.

They then use this rectified GNS to make their gin, by passing it through a pot still with botanicals etc.

Does anyone think/know if this makes any difference? Or is it as negligible/unnecessary as I think it is?.... and mainly used as a marketing gimmick!?

Many thanks in advance.

[John McKee]

No one is improving GNS (NGS) by redistilling it. They're doing it so their labels can legally say "Distilled by" or "Distilled at" rather than "Packaged by".

If you find contrary opinion, have them send a sample of GNS and their re-distilled GNS for lab analysis on a GC or GCMS and their argument will have evidence to the contrary.

Cheers.

[tl5612]

Thanks very much!

[mendodistilling]

I know of a place which uses a continuous still and takes their grape product up to the high 80's for making fortified wines, they make no cuts because they argue its not necessary. Maybe this is the case for you.

[bluestar]

No one is improving GNS (NGS) by redistilling it. They're doing it so their labels can legally say "Distilled by" or "Distilled at" rather than "Packaged by".

Cheers.

Can't they do that anyway by virtue of the final distillation of the GNS with the botanicals? Why would they have to distill it twice for the appellation "distilled by"?

[tl5612]

well... i assume it is just marketing spiel for a micro in London that sells both vodka and gin. http://cityoflondondistillery.com/index.php

they bought 2 Carl stills to start up. one pot still with gin head, and one column still.

the NGS is redistilled in the column still to make (be able to call it that i guess) 'distilled vodka'. that makes sense, as John pointed out.

they then use this red-distilled 'vodka' to make the gin.

i wondered two things really:

1) why did they buy 2 separate and expensive stills when only using NGS? (as they could do the vodka in the pot).

2) does the re-distillation of NGS in a copper still make any difference?

i assume that either they believe that it does improve the NGS, OR they bought the two stills purely to look good (they are in a bar) and add to their marketing story.

any thoughts?

[John McKee]

Can't they do that anyway by virtue of the final distillation of the GNS with the botanicals? Why would they have to distill it twice for the appellation "distilled by"?

I thinking more to TL5612's that this outfit claims to be making Heads & Tails cuts on a GNS, not true...we all know. If they are making gin, then of course the botanicals manipulation gives them the "Distilled by", but if they're redistilling GNS to get vodka (thereby getting to the "Distilled by" appellation) they're just making it worse.

TL5612, your question regarding redistillation of GNS in Copper.......distilling in Copper doesn't make a difference...regardless of GNS or base wash. Yes, copper is required at certain points in the distillation process, but all-copper-everywhere stills are a waste of money. Period. Anyone claiming otherwise doesn't have a full understanding of distillation of ethanol.

[tl5612]

thanks for your reply john.

apologies for going over the same ground again. but there is another (very popular) micro in London and they do the same thing (albeit on a hybrid pot still with a 6 plate side column, which is used for the NGS vodka run, and then bypassed on the gin run).

the go into great such detail in explaining their process that i assume they must think it makes a difference... making the cuts etc.

http://www.diffordsguide.com/class-magazine/read-online/en/2012-06-26/page-6/sipsmith

in the Vodka and Gin sections.

what are anyone's thoughts?

i assume there are many outfits in the States that do something similar?

thanks

[bluestar]

I am guessing now that it might be a difference between an European Union requirement on making of a London Dry style, versus TTB requirements for "distilled by". Since technically to be a London Dry you must start with vodka, perhaps the EU requires that it must be YOUR vodka? That would explain it. Anyone know the EU requirement on this, I don't?

[tl5612]

nope. just has to be neutral spirit. Beefeater, Bombay Sapphire etc. are all made with bought-in neutral.

in fairly sure that in the past UK gin had to be made with bought-in neutral due to a law from the age of the gin riots i think. the neutral couldn't be produced on site.. to avoid sub-standard gin/excise duty evasion (we used to have thousands of gin producers apparently).

if the re-distillation of NGS in a copper still truly does nothing, and cuts of heads and tails are not needed - then it is just marketing stuff. and i will settle for that.

[nick jones]

No one is improving GNS (NGS) by redistilling it. They're doing it so their labels can legally say "Distilled by" or "Distilled at" rather than "Packaged by".

If you find contrary opinion, have them send a sample of GNS and their re-distilled GNS for lab analysis on a GC or GCMS and their argument will have evidence to the contrary.

Cheers.

A GCMS is nice, and can tell you some things. But it is without question that the human palate can detect flavors that a GCMS is unable to detect.

I thought that this is as good a time as any to make a shout-out to the old tried-and-true "triangle" blind tasting: Take two samples and split them into three glasses, two glasses with identical samples and one glass with the different sample. Have a panel of tasters attempt to determine which samples are the same and which samples are different, and what the differences are. Without delving into statistics, I'll just say that you will usually be surprised by the results.

Like John, I thought that there would be no detectable difference (to the human palate) between GNS and re-distilled GNS. My tasting panels have shown me contrary evidence.

So to answer your question, tl5612, in my opinion there is only one way to know for sure: a blind tasting. Although it's hard work to set one up properly, it's usually not too hard to find willing volunteers to do the tasting.

Nick

[Copperstill]

TL5612, your question regarding redistillation of GNS in Copper.......distilling in Copper doesn't make a difference...regardless of GNS or base wash. Yes, copper is required at certain points in the distillation process, but all-copper-everywhere stills are a waste of money. Period. Anyone claiming otherwise doesn't have a full understanding of distillation of ethanol.

Just to clarify your saying that distilling in a copper still doesn't mater if your distilling things other than GNS?

[John McKee]

Just to clarify your saying that distilling in a copper still doesn't mater if your distilling things other than GNS?

Copper is required in only one place during the distillation process. My point was to communicate that building distillation equipment from solid copper is a waste of money. Think about the body of a pot still. Cut a cross section from that still wall and you have about 1/4" copper. Only the interior surface comes into contact with beverage alcohol....all of the rest of the copper will never see the spirits.

(Now some people are going to say that the copper erodes over time, so eventually, even that copper in the center of the still-wall cross section will see the beverage alcohol.....this is true if you run 5-10 MGY for 40 years. Not true for anyone one this forum making hooch.)

So....when asked by those looking at equipment, I try to suggest budget savings can be had in CAPEX costs for stills by purchasing system for their utility, not for their esthetic. If esthetic is your concern, by a stainless still and then have someone wrap if in thin gauge copper (cost you less than $6K for a 1600g pot still) and you have your show piece.

Cheers

[Copperstill]

Copper is required in only one place during the distillation process. My point was to communicate that building distillation equipment from solid copper is a waste of money. Think about the body of a pot still. Cut a cross section from that still wall and you have about 1/4" copper. Only the interior surface comes into contact with beverage alcohol....all of the rest of the copper will never see the spirits.

Just for the record. I can think of 4 places that the copper from a still affects the spirit 3 of which are in the still. Although copper isn't necessary for distillation it has a very positive effect on potable alcohol intended for aging. This includes under specific conditions the boilers(pots) affect on the spirit before it volatilizes hence why a full copper still is favored. I understand trying to be thrifty with money during a start-up but I personally I wouldn't recommend skimping on equipment that all your spirit is going to be made with.

[John McKee]

Just for the record. I can think of 4 places that the copper from a still affects the spirit 3 of which are in the still. Although copper isn't necessary for distillation it has a very positive effect on potable alcohol intended for aging. This includes under specific conditions the boilers(pots) affect on the spirit before it volatilizes hence why a full copper still is favored. I understand trying to be thrifty with money during a start-up but I personally I wouldn't recommend skimping on equipment that all your spirit is going to be made with.

Can you please describe the chemical reactions that take place at those 4 places? Chemical Engineers in both industrial and beverage ethanol can only describe 1. I would very much appreciate (honestly, not being sarcastic here) you sharing your understanding of the other 3 reactions you describe.

Thanks in advance.

Cheers.

[Copperstill]

Give me a call I'd be happy to talk with you about it. My number is in my info. That one thing you are referring to is volatile sulfur compounds?

[tl5612]

it would be great if this conversation could remain on the forum if at all possible.

i know there are quite a few who are interested in this conversation and would like to know more about copper stills etc.

thanks

[PeteB]

Copper is required in only one place during the distillation process. ............................ Think about the body of a pot still. Cut a cross section....................................

I am going to build another whisky still soon, so I am very interested in the recent posts above regarding the placement of copper.

John obviously has vast experience in the industry but I am still not sure where the copper should be. I have been lead to believe that the copper should be in the vapour path! Is that correct? or should it be in the pot as your above post seems to suggest? maybe that is not what you are saying

John, where is "only one place" that copper is needed?

Thanks

Pete

[JohnD]

All due respect John but as a fellow GCMS enthusiast I have to say that the differences in the pallet effect of a copper rectified NGS and non are pretty extreme. I was never able to confirm it analytically but my guess is that NGS having been produced on stainless equipment has sulfur compounds in it that are removed by the copper contact during rectification on a copper still. That's not to say that the entire still need be made from copper, I believe sulfur is removed at the point where vapor is condensed against the copper helmet or column.

[John McKee]

All due respect John but as a fellow GCMS enthusiast I have to say that the differences in the pallet effect of a copper rectified NGS and non are pretty extreme. I was never able to confirm it analytically but my guess is that NGS having been produced on stainless equipment has sulfur compounds in it that are removed by the copper contact during rectification on a copper still. That's not to say that the entire still need be made from copper, I believe sulfur is removed at the point where vapor is condensed against the copper helmet or column.

John,

You're spot on, the copper contact can be a "demister pad" or other copper packing in the vapor path. In a still, say the size of Buffalo Trace's, that pad is about 4'-5' across and about 4' tall. Its a consumable that is replaced on a regular schedule. The remainder of the still is made from SS and some other mild steels. The demister pad acts as the contactor, condenser, and chemical reagent for the sulfur compounds.

So yes, to be clear, Copper is required, but not in the amounts that one typically sees in the construction of an artisan-scaled still system.

Cheers.

[JohnD]

John,

Have you seen any data on SA/V ratio of copper to liquid and sulfur binding or concentration of esters produced in distillation etc? I can't find anything and that always makes me mad. Someone has this info.

[Copperstill]

it would be great if this conversation could remain on the forum if at all possible.

i know there are quite a few who are interested in this conversation and would like to know more about copper stills etc.

thanks

I see that both Johns have already discussed the effects of copper on sulfur compounds so I’ll skip that. To my understanding the physical characteristic of the copper boiler/kettle creates very unique situations during still runs, in conjunction with high heat ,and acidity from the wine/wash. These conditions allows one the discretion of pitching heads back into the pot without a build up of these compounds through multiple still runs because again to my understanding the still is creating new compounds through the coppers catalytic properties, heat , and aromatic precursors that have formed on the surface of the boiler and the inside of the still. High heat also aids in the formations of guaiacols, and 2-phenylethanol which are found in pot-stills, but not significant quantities in column stills. Maillard reactions make furfural and desirable sulphur compounds. This all said I know that some of these reactions happen without the presence of copper, but IMO all copper Alambic stills are the way to go for barrel aged spirits.

I said that there are three places that I understand that reactions take place in the still here they are.

• boiler/kettle surface
  
• the transition where the vapor is volatilized out of the liquid mixture (reactions happen anywhere vapor, and copper are in contact really but are highly reactive during the transitional phases)
  
• the transition where the vapor goes back to liquid. I’ve read that the concentrations of fatty acids are affected by the output temp of the spirit, and it is my experience that this is true. In my opinion this allows one to shift the final flavor of aged spirit depending on what you what you are looking for.
  

[Jedd Haas]

the copper contact can be a "demister pad" or other copper packing in the vapor path. In a still, say the size of Buffalo Trace's, that pad is about 4'-5' across and about 4' tall.

I'm familiar with the copper mesh packing that's readily available. I've also seen pictures of a copper catalyzer supplied with one of the German stills; this latter item appeared to be a large roll of corrugated copper. But what is the format of the demister pad? Do you have a picture of one you can post?