Worm condensers and flavour?

[Admiral]

I was reading Dave Broom's piece on Yamazaki distillery in Issue 41 last night, and I was struck by his comment that worm condensers add to the flavour.

Why would this be the case? I would have thought that every process or element that could possibly affect the flavour or body of the new make spirit would take place BEFORE the vapour passes over the lyne arm.

Once the distilled vapour passes over the lyne arm, all it can possibly do is condense. So why should worms produce a different flavoured or textured condensation to any other process?

Any thoughts?

Cheers,
Admiral

[bamber]

Presumably the copper pipers that make up the condensers provide a platform for chemical reactions to take place.

The type of reactions may depend upon, the time the distillate spends at various temperatures and also (I guess) the pressure within the tubes during the cooling process.

Consider that the yield of the Harber process is very dependent upon the catalyst, temperature and pressure used.

[Ash]

I would have thought that every process or element that could possibly affect the flavour or body of the new make spirit would take place BEFORE the vapour passes over the lyne arm.

Once the distilled vapour passes over the lyne arm, all it can possibly do is condense. So why should worms produce a different flavoured or textured condensation to any other process?

Any thoughts?

Cheers,
Admiral

Thats true, Admiral, vapour is vapour. But the theory is; how you collect/condense the vapours will have an effect on exactly what vapours you collect. The condensing equipment cant change the process but it can change which part of the by-product you are harvesting. Thats why distilleries swear by the particular shape and size of their stills. Morangie for instance have very tall spindly ones, which, because of their enormous height, they claim will only condense/collect the finest purest vapours which in turn produces a very light spirit. Contrast to Macallan which has miniscule dumpy stills, producing something entirely opposite.
Having said that, I cannot believe anyone could deduce from tasting a whisky how it had been condensed. Perhaps I am underestimating the bloke.
Ash

[Admiral]

I agree 100% with what you've said, Ash, but with regards to the size and shape of the still, this is basically an element that affects flavour before the vapour passes over the lyne arm. Yes, it certainly affects the type of vapour that is produced - but - I still maintain that once that vapour passes over the lyne arm, it can physically only do two things: Cool down, and then condense back into liquid. I would not have thought that the shape or material of the housing in which the vapour cools and liquifies would influence flavour. At least certainly not to the point where Dave Broom would make such an assertive remark about it.

Unless of course a worm condenser actually forces or encourages vapour backwards along the system and pushes it back over the lyne arm where re-flux and redistillation can then occur? Is this a possibility?

I agree also with Bamber that reactions between the copper & the wash occur in the still during the distillation process (this has been reasonably well documented by numerous authors & scientists in the past), but this is encouraged by the high temperatures and the reflux action.

I doubt (although I could be wrong) that a chemical reaction would occur at the much lower temperature present at the point of condensation. Afterall, if a chemical reaction simply occurred between water & copper at cooler temperatures, all of our domestic piped water & taps in our houses would suffer the same fate.

I'm not trying to discredit or disagree with Ash's or Bamber's replies here, but I'm hoping to encourage more thought & dialogue on the topic.

[bamber]

It is a tricky one and whisky making, like good cuisine, is a fine balance between art, science and myth.

Maybe it does not make much difference, but I suspect that it does - I think Dalwhinnie use worm condensers. The actual process is undoubtedly exceedingly complex - scope for a PhD ? That would be fun !

With regards copper not reacting, with the wash, that may or may not be the case but it could also act as a catalyst for 'intra-wash' reactions and the surface area and shape of a catalyst certainly does affect its effectiveness.

Maybe the worm condensers affect the pressure, within the still.

[Admiral]

Hmmmmm....possibly.

I think you make a good point in saying that whisky making is a fine balance between science, craft, and myth. And I agree with you entirely.

But why would Dave Broom say so assertively that the resulting malt is sweeter? He claims it with such conviction that I'm led to believe this is the science side of the balance!

Sweetness in a malt is usually said to come from either the barley strain (i.e. golden promise); the conversion of sugars into alcohol during fermentation; and, mostly, the cask (i.e. sherry wood).

I don't suppose Dave participates in these forums, does he?

Cheers,
Admiral

[bond]

Thats a question I have been wanting to ask.

Do you suppose the leading whisky writers in the world would be visiting these forums to check what serious whisky folks all over the world think of them and their tastings?

I would if I was one ! (Know thy consumer)

[bamber]

The only way to test if the use of worm condensers necessarily makes for a sweeter whisky is to try the same stills with and without them. Like you say, there is a lot a factors that contribute to the sweetness of a whisky and by just looking at the condensers and tasting the 10YO product you may draw erroneous conclusions.

Correlation is not the same as causation. I keep my olive oil in an Ardbeg bottle but that doesn't make it peaty !

All that being said, they may make for a sweeter malt and if someone could explain why, I'd also be very interested.

Its the purity of the whisky making process that makes it so good and so hard to know what separates the great from the good.

[Deactivated Member]

Hi,

No matter what type of condenser you use, it will have some influence on the character of the new make spirit. If we look at the questionable worm tube, you'll see because of its shape and size, the new make will take some time to get to the spiritsafe. Because of the previous 'spirit runs' the new make leaves a residu behind, possibly created by the interaction of the copper and the new make spirit. Distillers believe that, this specific residu will add something to character of the new make spirit, and I believe that they are right. Now it's very dificult to say weather it's sweeter or not, it's possible that it will add a certain sweetness to it. It's also a matters what type of spirit will be created on wich a worm tube will add the last part to it, think of types like: peaty, robust, oily, estery etc etc. And that will decide the out come. A little sweetness perhaps? or some desirable bitter notes? Or maybe something else, like less peaty than expected for example? All is possible

There's even a distillery (can't remember the name right now, but I have heard of it) wich use a horizontal tube condenser. Why? A matter of flavor perhaps? Yes I think so, it's almost similar to the worm tube like condenser, not entirely, but some similar characteristics. Except this one uses tubes instead of a worm and the steam preasure must work quite hard to let the liquid flow to the spirit safe.

For what it's worth,

Erik

[Xavier]

Hi all,

In the industry two types of condensers are used (worm and tube). Linkwood for instance uses both, and apparentlywith a great influence on the whisky's style (see infra). That means that there is definitely a certain effect during the condensation of the wines, and the effect is caused by the surface area of the copper used. If there is a difference between tube and worm condenser, maybe there is are differences between different types of worm condensers too... (depending on the copper surface area). Well, that's how I see it. The question remains how copper can react on condensed (thus cooled) liquids. Anyone ?

Here are two interesting texts :

http://www.undiscoveredscotland.co.uk/u ... enser.html

Condensers come either as tubes or worms. The worm condenser comprises a coil of copper tubing immersed in a large circular tank of water, usually raised above ground level. A good example of this is at Dalwhinnie Distillery, where the large worms, often mistaken for water tanks, sit outside the front of the distillery. The vapours enter at the top and the condensed liquid emerges at the bottom.
The tube condenser brings the idea up to date, and is more efficient than the worm. It operates like a reversal of the processes inside a steam engine. The condenser is tubular in form and made of copper. It stands on one end and contains a series of copper tubes through which cold water is piped. Again, the vapours enter at the top of the condenser, and the liquid flows out of the bottom.

http://www.maltadvocate.com/malt/html/am_cop.html

Copper definitely needs to be in the distilling process, and building your still out of copper is one way to put it there. But Bill Lumsden feels the most important place for the copper is where it will do the most good; where the hot vapors are condensing.
“ Compare whisky made in a distillery where they have what you call shell and tube condensers,” said Lumsden, “where the neck of the still goes over into the lyne arm into this large copper column, inside which there are up to 250 narrow copper tubes. We pump cold water into these tubes, so the vapors condense out and run down to be collected. Compare that to the more traditional method of condensing, which we call worm tubs—this is basically a large tank or vat of cold water, into which the neck of the still coils round in an ever-decreasing diameter of copper pipe, just like a worm coil, but thin-sided.
“ The surface area of copper available to the vapors in a worm tub,” he continued, “is a fraction of that you have in a condenser. The whisky made in a distillery with worm tubs is typically much more meaty and sulfury in character. The only distillery I know of which currently utilizes both types is Linkwood distillery. I was posted there as a trainee manager in my distiller’s days, and I did a few experiments on my own, looking at the two different spirits. I could pick out the difference, nosing and tasting blind. There was such a distinct difference. That’s a quite dramatic illustration of how having a greater surface area of copper can really make a great impact on your spirit.”

Ciao
Xavier

[Lawrence]

I would have thought that every process or element that could possibly affect the flavour or body of the new make spirit would take place BEFORE the vapour passes over the lyne arm.

According to "Whisky, Technology, Production and Marketing" Volume Editor Inge Russell says:

Lyne Arm

The lyne arm, lye pipe or vapour pipe is of cylindrical construction and connects the head to the worm or shell and tube condenser. The attitude of the lyne arm has an important bearing on the spirit characteristics. It can be designed to be horizontal, ascending or depending to the condenser or worm tub, and may be short or long. Such permutations as there are will affect the nature of the new spirit. The lyne arm can be interrupted by a purifier-a device fitted with baffles and cooled by an external water jacket or an external coil. It is used to encourage heavy oils (higher fatty acid esters) to return to the still during distillation. The purifier returns the oils to the shoulder of the pot via a u-bend."

He gives no indication that the worm tub or condenser has any affect on flavour however I will keep researching.

However he does say that the attitude of the lyne arm has "an important bearing" on the spirit. I read this as nothing happens in the Lyne arm, it's what it allows to pass and what is returned to the still. I think the second para of Xavier's post with the quote from Bill Lumsden answers the question.