Stainless Holding Tanks

[fussychicken]

Roger brought up a good question in the Hirsch 16 thread that I thought was worthy of its own thread. This is also something that I have thought about before because of its relevance to some of the whiskeys we know and love:

Yep, but does it change over time?

We know that whiskey changes in a glass left out overnight and a bottle with a goodly amount of airspace will change if left for a period of years. When I asked about BT's stainless tanks I was told that they have no special measure to prevent an airspace - so if the tank is half empty, it's half airspace, and allows for a lot of interaction.

Anyone have any further info they would be willing to share?

It seems to me that you would want a movable "roof" on these tanks to keep the airspace to a minimum. Either that, or displace the air with Nitrogen. Sure these tanks would probably be fine for a couple of months, but what about stuff that is held in stainless for years? (VWFRR anyone?)

[barturtle]

There is much we don't know about the tanks they use and how they use them (or at least I don't know)

-they are likely sealed tanks to prevent evaporation

--if so, think of it as a keg or even a very large bottle, it only saw fresh air a few times

--I would guess the less times it's exposed to fresh amounts of air the less it will get affected

-Which part of air is the damaging part?

--Atmospheric air is mostly Nitrogen ~78%

--Oxygen ~21%

--Near sea level Water vapor makes up 1-4% that is not included in the dry percentages

-If the tank is like a keg, could they or do they use a CO2 or N2 push?

Every time you open a bottle the head space gets replaced with fresh air (at least partially) meaning every time it gets opened the product gets slightly more damaged or even diluted as alcohol is hygroscopic so it absorbs the water from the air. In a sealed tank only the volume of liquid removed is replaced with air, in a bottle it would be more than the volume removed as the opening can breath regardless of volume removed.

If the tank is tall and narrow the amount of surface area to total volume is lower, slowing the rate at which the air can affect it, unless you were to shake the whole damn thing.

As far as some sort of expand/contract mechanism, I'd say don't. Any sort of mechanism is going to increase the chance of leaks (air or liquid), increase the cost of the tank, and even risk the whiskey as wear in the mechanism may introduce slivers of unwanted material into the whiskey, possibly affecting the taste or the product.

I would think long term storage in these tanks is more stable than a bottle you open a few times a year over the same period of time.

[cowdery]

The tanks definitely are sealed and to the extent possible, they will try to use a tank that is just the right size for what they are storing in it, so the air can be kept to a minimum. Nobody in Kentucky, so far as I know, is using any kind of inert gas to prevent oxidation and, yes, it's oxidation they're trying to avoid, so it's the oxygen in the air that is the culprit.

Julian Van Winkle has speculated about using something like nitrogen to displace the oxygen but I don't think he's ever tried it. Oxidation is the concern, not any kind of reaction with the steel itself.

We know the Hirsch was tanked before the final batch was bottled and Julian has tanked his rye and maybe some of his bourbon too. Otherwise, it's not a common practice.

[boone]

We have nearly 50 stainless steel bottling tanks. That's not counting the tanks in the "sugar shack" affectionately named for what it is :grin: :grin: :grin: That's were all the sweet stuff is made ...

None of these tanks are airtight and no product is held for years and years as Uncle Everett's stuff :grin: :grin: (Hirsch).

A little tanking 101 :grin:

Many are 14,000 wine gallon capacity. From time to time they need to be gaged to see how many feet and inches are left inside. You cannot get a "exact" bottle count by the paper's nor by a visual...Cases get smashed bottles get crushed, the float sticks on the filler etc...etc...etc...

A visual is made from a large hatch on the top of a tank (on a cat-walk) These tanks are so huge you can stack several compact cars inside each one. To gage, a air line is turned on (just for a bit) that will blow any air locks out of the line...and then the meter will bob till it hits the fill point mark... with this fill point mark you will view a chart on the worktable...it will calculate how many bottles for each size bottle, till it's empty----This is important when a specific tank needs to empty and the cases are printed...You will know within a layer of how many cases to put on the line so you won't have to unload a ton of them at the end...

Circulation of product is a necessity quite often. Many times the lines need to circulated with 100 proof vodka to clear the lines after a wash out---blown dry...then another circulation from filler thru a 250 gallon boot line to the tank farm to the tank, stirred, then back to the filler for at least seven minutes...then pumped back into the tank. The proof is checked...then a re-drop for bottling.

I hope this helps in the understanding just a tad bit of what goes on in a bottling house (tank farm) :grin: :grin:

Roger brought up a good question in the Hirsch 16 thread that I thought was worthy of its own thread. This is also something that I have thought about before because of its relevance to some of the whiskeys we know and love:

Anyone have any further info they would be willing to share?

It seems to me that you would want a movable "roof" on these tanks to keep the airspace to a minimum. Either that, or displace the air with Nitrogen. Sure these tanks would probably be fine for a couple of months, but what about stuff that is held in stainless for years? (VWFRR anyone?)

[NickAtMartinis]

Bettye Jo, that's a lot of info. Thanks. It sounds like a lot of air can circulate within these tanks. But as you state, the bourbon you have in them isn't there long so that's obviously good.

However, this does explain why Hirsch has apparently changed considerably over time.

Also, why the holding tanks if the bourbon isn't going to be in them long? Is it just for bottling purposes? Are these tanks only for premium bourbons?

Again, thanks for the info.

Regards,

Mark

[boone]

From the barrel (dump room) it's pumped into a processing tank, sometimes upstairs to be immediately processed and sometimes outside (yeah, you wouldn't believe the tanks in the back of HH) until they can get to it. This does not happen often because when we run my line, 1.75 glass and the 1.75 plastic line, on the same bottling tank it will pump it dry in less than two hours :bigeyes: ... we always have several back-up bottling tanks ready to go, every shift.

After processing, chilled/cut to order it's then "brought over" to a bottling tank...QC will test it for taste/proof/color/gage etc...and the paper work is then tagged for bottling...

Every filler in the bottling house is under vacuum to fill the bottles...only two are gravity fed. Bourbon is bounced around...more than you think.

The single barrel is another story all to itself...There's a separate dump and (small) processing tank just for single barrel... After processing they are pumped into 55 gallon drums and dumped (by one person) into the filler in WLD...That's where all the single barrel products are bottled/labeled/cased :grin:

Bettye Jo, that's a lot of info. Thanks. It sounds like a lot of air can circulate within these tanks. But as you state, the bourbon you have in them isn't there long so that's obviously good.

However, this does explain why Hirsch has apparently changed considerably over time.

Also, why the holding tanks if the bourbon isn't going to be in them long? Is it just for bottling purposes? Are these tanks only for premium bourbons?

Again, thanks for the info.

Regards,

Mark

[NickAtMartinis]

From the barrel (dump room) it's pumped into a processing tank, sometimes upstairs to be immediately processed and sometimes outside (yeah, you wouldn't believe the tanks in the back of HH) until they can get to it. This does not happen often because when we run my line, 1.75 glass and the 1.75 plastic line, on the same bottling tank it will pump it dry in less than two hours :bigeyes: ... we always have several back-up bottling tanks ready to go, every shift.

After processing, chilled/cut to order it's then "brought over" to a bottling tank...QC will test it for taste/proof/color/gage etc...and the paper work is then tagged for bottling...

Every filler in the bottling house is under vacuum to fill the bottles...only two are gravity fed. Bourbon is bounced around...more than you think.

The single barrel is another story all to itself...There's a separate dump and (small) processing tank just for single barrel... After processing they are pumped into 55 gallon drums and dumped (by one person) into the filler in WLD...That's where all the single barrel products are bottled/labeled/cased :grin:

Thanks, Betty Jo. I've got to get down there for a tour one day with my family. That's some really interesting stuff.

Just a quick question, does all the "bouncing around" that you mentioned have any negative affects on the bourbon whatsoever?

Thanks,

Mark

[boone]

I've worked in a bottling house for over 15 years now...I've toured many of the other distilleries, it's all done nearly the same way. We have nearly the same equipment with exception of this new line we are putting in right now and the de-palletizer (all robots, 4 of them) ...some really high tech stuff. But, in general all the other 8 lines run in the same manner as the rest of the other "major" processing and bottling departments :grin: :grin:

So...to answer you question?

In my opinion, I don't think anything "negative" happens...In that, I mean to say the outcome does not produce a bad taste...cause I still like it :grin: when we get done with it :grin: :grin:

Although, many will say the best they have ever tasted has been directly from the barrel. I can't argue with that :grin: Some of the best I've tasted have been right from the barrel :grin: :grin: :grin: too...

Many will say that just cutting bourbon down to normal strength is a negative thing. I guess if you look at it from that point of view then there it is...a matter of personal preferance...

Thanks, Betty Jo. I've got to get down there for a tour one day with my family. That's some really interesting stuff.

Just a quick question, does all the "bouncing around" that you mentioned have any negative affects on the bourbon whatsoever?

Thanks,

Mark

[fussychicken]

First off, thank you Bettye Jo for the great info!

Secondly, it appears that John Hansell from Malt Advocate is either lurking on the boards, or simply read my mind. Here is a great post about stainless tanks, specifically at BT and Saz 18.

http://blog.maltadvocate.com/2008/01/10/inside-scoop-sazerac-rye-18-year-old/

A couple of thoughts and highlights:

• Our hunch they they tanked the Sazerac 18 year is correct. This was apparently done 2 years ago.
  
• This then means the evaporation loss listed on the 2007 Sazerac 18 year info sheet is incorrect.
  
• If you believe the info sheet information of the Saz 18 being barreled in 1985, and then added with this new info of being tanked in 2005, that would make the Saz18 20 years old.
  
• Based on my calculations using the info sheets, and also looking at Mark's comments about the tanks they are using to hold this rye, it looks like BT plans on using this tanked source for at least another 5-8 years for Saz18.
  
• The stainless tanks at BT sound pretty much like Chuck described.
  
• If you believe John Hansell's taste buds, there is indeed changes happening in the tank. Since it appears that the level of air in the tanks is not always controlled most of the flavor change is coming from this oxidation. It also appears that aeration from moving the whiskey around can change the taste.
  
• Finally, Mark Brown, what can I say?!? Are you too scared to post on our boards here?!?! We don't bite! OK so at least most of us don't.

Sadly, I get the impression that many of the knowledgeable folks in the industry read this board all the time but do not post. Probably so they don't get bombarded with questions they can't answer, don't have the time to answer, or aren't allowed to answer. I can say I understand although it is frustrating. My many thanks to the Ken Webers, Julian Van Winkles, and Bettye Jos for the posts that you guys and gals do make.

To the admins of the site: Do you think we could set up some sort of place that was "safe" for the Industry guys to field questions every once and a while (maybe once a year)? Maybe kind of like BOTM, but maybe have a thread where we debate over a list of burning questions we have for a particular distillery and then have the results posted?