Variable capacity tanks & IBC's

[nick....@gmail.com]

Hello,

Reading through some old posts I had a thought and hoped I might be able to get some input in what the likelihood of it working would be.

Can someone who has or has knows the workings of a variable capacity tank could offer some advice.

In short, How do they work?

The reason I ask is I am wondering if an IBC could be given a 'swimming pool cover' that floats on the surface, cut from bubble wrap or an actual pool cover (food grade is available) and would this make any real difference? 

I'm thinking it would reduce the surface area in contact and hopefully the oxidization although there would still be air in the top of the tank

I do keep my tanks as full as possible, but some times have tanks with head space and haven't yet got a good system to top up with Co2.

Best Wishes

Nick

Wiltshire

[Cheshire Matt]

Or consider what I've done and hire a collapsable IBC from Arlington Packaging and put a 1000L Bag-in-Box in it.  May not be ideal/economic for everyone depending on how long they need it for and total capacity required, but it's helped me out of a short-term space/capacity squeeze.

http://arlingtonpackaging.com/test/COMBO/index.html

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[Andrew Lea]

On 10/04/2014 21:30, nickh...@gmail.com wrote:

>

> Can someone who has or has knows the workings of a variable capacity
> tank could offer some advice.
>
> In short, How do they work?

I have one which is a Speidel circular tank in stainless steel. It has a
circular stainless steel lid which fits neatly inside. The gap between
the edge of the lid and the inside surface of the tank is filled with an
inflatable silicone rubber tyre which you pump up with a device similar
to a bicycle pump. The lid has a threaded sealable vent built in and
also an eye so you can attach a rope and control the height of the lid
in the tank before you fully inflate the tyre to hold it firmly in
place. The lid is normally placed just above / touching the surface of
the liquid to minimise headspace. After that you close the vent, and
then pump up the tyre. It works fine and I have held finished cider in
it for over a year prior to bottling. Just need to check the tyre
pressure every so often.

>
> The reason I ask is I am wondering if an IBC could be given a 'swimming
> pool cover' that floats on the surface, cut from bubble wrap or an
> actual pool cover (food grade is available) and would this make any real
> difference?

It would have to be totally air impermeable and sealed to be truly
effective. That means all the way round the edges as well as being
impermeable to gas diffusion. I don't think bubble wrap or pool liner
meet those criteria very well.

Matt's suggestion is good, but alternatively and very cheaply you can
just use olive oil in an IBC and it will float on top as a seal (very
old idea - the Romans used to do it). I found you need about 3 litres of
oil for about a 3 mm cover depth in a 600L IBC. It's easy enough to
calculate once you've measured the surface area. That will hold the
cider about 6 months I'd say. (Remember the IBC itself is also air
permeable through the walls). It works like a plastic film but its
advantage is it gets right to the edges to give a total seal.

Andrew

--
near Oxford, UK
Wittenham Hill Cider Portal
www.cider.org.uk

[skidbro...@tiscali.co.uk]

Hello Nick

I use 500 litre vari-fill tanks when breaking down larger tanks. They work by having a floating lid that has an inflatable ring around it that can be pumped up to exclude the air. They are very easy to use and very effective and allow you to leave relatively small volumes of cider safely. They are not overly cheap.

I suspect that cider spoilage organisms may quite rapidly find a way around bubble wrap. Pesky things.

For a relatively cheap but very effective way of excluding air from part full IBCs: You might want to talk kindly to Bob Honey at Honey and Daughter Cider. He has an excellent system with a CO2 cylinder connected to a valve mounted in the top of the IBC. I think that he got the bits from Mole Valley Farmers and depending on where in Wiltshire you are that might be very easy for you.

Best wishes

Guy  

--

[greg l.]

Adding CO2 doesn't exclude oxygen, they can both quite happily fill the same volume of gas. There are "skins" for winemaking to cover the surface, I don't know how well they work or how popular they are.

Greg

[skidbro...@tiscali.co.uk]

Hi Greg

Fair point well made. 

Guy

[Peter Ellis]

On 11/04/2014 09:37, greg l. wrote:
> Adding CO2 doesn't exclude oxygen, they can both quite happily fill
> the same volume of gas. There are "skins" for winemaking to cover the
> surface, I don't know how well they work or how popular they are.
>
> Greg

Winemakers here generally use Nitrogen piped from ceiling systems.
Traditionally, olive oil was used. Some also use open topped s/s tanks
with floating lids.

Cheers

--
Peter Ellis

Porec Sales Office
Croatia Property Services

Selling in the new Tuscany!

Tel +385 (0) 92 247 5879
+385 (0) 91 400 3784

peter...@croatiapropertyservices.com
in...@croatiapropertyservices.com

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[greg l.]

Here is an link about the "skins"

http://www.flextank.com.au/skins.htm

Greg

[Cheshire Matt]

I tried this couple of years ago? Yes, it does work, but the drawback
you get is trying to get the olive oil out of the barrel. I guess if
you're *always* going to use olive oil in the barrel then a few floating
"circles" of it on the surface will get added to.

However, for me, I found it a real bugger racking it. Normally I could
tolerate a little bit of any film yeast to slip through the bottom tap
as it got broken up. But allow any olive oil through and then it's in
your bucket/demijohn/bottle whatever. And then you have to clean that.
To not have the oil come through you have to rack a lot less.

Overall I felt the wastage of cider was worth more than the risk of
spoilage for the time I had it in the barrels.

[Tim]

That being the case why do I bother injecting Co2 into part barrels and the cider does not go off???

 

Tim in Dorset

[greg l.]

Do you ever get film yeast in your barrels? I have not heard of part filled barrels being used, usually they are kept topped up. Co2 can be used to flush air out, but if o2 can get in, co2 won't stop it.

Greg

[Andrew Lea]

On 11/04/2014 09:42, Cheshire Matt wrote:
>
>
> However, for me, I found it a real bugger racking it. Normally I could
> tolerate a little bit of any film yeast to slip through the bottom tap
> as it got broken up. But allow any olive oil through and then it's in
> your bucket/demijohn/bottle whatever. And then you have to clean that.
> To not have the oil come through you have to rack a lot less.

Point taken Matt, but an IBC has a bottom tap and is translucent so you
can see the oil / cider interface and stop just before you get there.
If you 'chock' the tank toward the tap you don't lose so much.

The oil does float of course, though if you disturb it overmuch it tends
to emulsify a bit and takes a few hours to separate again. Yes it does
reduce the total recovery and it is awkward to clean the oil out
afterwards. Your flexible bag option is much better. But mine is a cheap
and workable solution which costs only a few quid and is easy to
implement. There is a trade-off of course!

[Tim]

At some stage everybody will end up with part barrels unless you process the whole lot in one go, I squirt in Co2 and have little in the way of yeast film, yeast film aint all bad, it does not taint the cider and once spotted indicated you are just about on the lee’s.

 

You must remember that I still make cider in the traditional way and not with a chemistry set.

[greg l.]

John Dalton died in 1844, this stuff isn't exactly new.

Greg

[Andrew Lea]

On 11/04/2014 10:37, greg l. wrote:
>
>
> John Dalton died in 1844, this stuff isn't exactly new.

I think there is a confusion in this discussion between

1. Positive swept physical displacement of air by CO2, which can be
total if it's properly managed afterwards. Though its tricky because CO2
is soluble in cider. N2 is in some ways better because it's less
soluble. In wineries a mix of N2 and CO2 is often used to control the
solubility issue.

2. Partial pressure solubilities of CO2 and O2 in air, which as Greg
says can co-exist at equilibrium levels (which is where Dalton's Law
comes in).

I think you're both talking about different situations.

[greg l.]

I did say co2 can be used to flush air out, which is I think what you are saying. My point is that having the headspace full of co2 doesn't stop o2 getting in, which is a common misconception.

Winemakers have a problem with using co2 because dissolved co2 is a fault in table wine, unlike cider. 

Greg

[Andrew Lea]

On 11/04/2014 11:17, greg l. wrote:
> I did say co2 can be used to flush air out, which is I think what you
> are saying. My point is that having the headspace full of co2 doesn't
> stop o2 getting in, which is a common misconception.
>

If it's sealed after it's flushed, no more air can get in. The problem
is that CO2 dissolves in cider hence creating a partial vacuum in the
headspace which then tends to suck more air in unless the seal is very
good. In practice small cidermakers here do find that CO2 flushing of
part-filled vessels does work well in practice as long as the ingress of
new air is restricted as far as is possible.

[greg l.]

My biggest bugbear is when people refer to "a blanket of co2 protecting the cider" or similar terms. A blanket of co2 isn't going to protect your cider at all.

Greg

On Friday, 11 April 2014 20:26:48 UTC+10, Andrew Lea wrote:

[Andrew Lea]

I have to disagree if the headsoace is purged and no more air can get in, that blanket will protect. Plenty of people here can verify that. 

Andrew

Sent from my iPhone

[greg l.]

But it's not the co2 that is protecting the cider, it is the seal. If the container is co2 permeable like IBCs it is no protection at all. Much better to rely on a good seal and minimal headspace.

Greg

[greg l.]

I meant O2 permeable.

Greg

[Andrew Lea]

I see where you're coming from, but if at time 0 all the headspace is CO2 and none is air or O2, then that is protective. As time goes on, the CO2 dissolves in the cider and air is pulled in through seal leaks etc. But in practice the CO2 is higher than atmospheric and the O2 is lower for quite a long time. 

How long a time? You'd have to talk to the people who do this here, but AFAIK in practice they would re-flush with CO2 every 2 to 4 weeks or so. Or of course every time they take out a new batch of cider for BiB or whatever. 

It is a meta stable non equilibrium system it's true. But people here wouldn't bother with it if it didn't work. 

I don't do it myself because my scale is so small it's easier to use full sealed vessels or my variable capacity tank to minimise headspace. 

It's really for people who need to run off a partial batch from bulk for sale every few weeks or so, not necessarily a long term storage solution. 

Andrew

Sent from my iPhone

[Wes Cherry]

This year, I started filling and topping up airspace in tanks by bubbling CO2 thru a carbonation stone attached to the racking port of my tanks. I let it go for quite a while. My setup has a sight glass so I can set the co2 flow rate such that fine bubbles rise up. CO2 is slightly heavier than air so the diffuse CO2 emerging from the top of the cider should form a blanket that displaces the air out of the airlock with minimal mixing. This is better than squirting in from the top where you rely on dilution to displace the air. Also, I figure the CO2 will be supersaturated in the cider, providing a reserve of CO2 for the headspace.

Some of my tanks are outside and subject to a greater diurnal "pumping of the headspace" as the headspace temperature swings low and high night and day (and thus the pressure follows from the ideal gas law). A 10C temp swing will pump about 4% of the headspace volume, assuming a 0 psi cracking airlock. The plastic ones on my Letina tanks are rated at 0.05 psi. That same 10 degree swing equates to about a 0.5 psi difference.


-'//es Cherry
Dragon's Head Cider
Vashon Island, Wa US
www.dragonsheadcider.com

>

[Ray Blockley]

Been following this with interest. Does the dissolved CO2 add to the acidity (perceived or otherwise) in the cider or is it so minimal as to be undetectable in cider? Just thinking of the comparisons with beer served under a CO2 blanket (at atmospheric pressure or greater) where some commentators are adamant that the dissolved CO2 alters the flavour.

Or is that perculiar to beer served from cask & no pressure / added CO2...?

Ray

[Andrew Lea]

On 11/04/2014 17:02, Ray Blockley wrote:
> Been following this with interest. Does the dissolved CO2 add to the
> acidity (perceived or otherwise) in the cider or is it so minimal as to
> be undetectable in cider? Just thinking of the comparisons with beer
> served under a CO2 blanket (at atmospheric pressure or greater) where
> some commentators are adamant that the dissolved CO2 alters the flavour.

Dissolved CO2 in cider definitely adds to both the perceived and actual
measurable (titratable) acidity. Not minimal at all. That's why you
have to boil it off before measuring 'fixed' acid. It also has a flavour
altering effect on the whole beverage. That's why Greg said earlier that
CO2 acidity in wine is undesirable (arguable) but in cider is desirable.
Saturation solubility is 2g/L. Many white wine makers target around 1
g/L quite deliberately to get the flavour balance they want. In many
ways one needs to regards CO2 as an 'ingredient'. It does a lot more
than just add bubbles.

A cask beer if properly conditioned will surely be saturated /
supersaturated with CO2 anyway? Isn't that the whole point?

[Wes Cherry]

All my ciders are carbonated so it doesn't matter.  Dissolved CO2 is definitely part of the flavor profile.   I find ~2vol CO2 to be roughly equivalent to 0.25 to 0.5 g/L of malic in perceived acid/"bite".

[Tim]

That’s what I do, it works well.

 

Tim in Dorset

 

From: cider-w...@googlegroups.com [mailto:cider-w...@googlegroups.com] On Behalf Of Andrew Lea
Sent: 11 April 2014 11:58
To: cider-w...@googlegroups.com
Subject: Re: [Cider Workshop] Variable capacity tanks & IBC's

 

I have to disagree if the headsoace is purged and no more air can get in, that blanket will protect. Plenty of people here can verify that. 

[Ray Blockley]

Thanks for clarifying that, Andrew.

Not a cask beer expert (at all...) but AFAIK cask beer relies on being vented to atmosphere & being able to "breathe" so much of the dissolved CO2 comes out of suspension while still retaining enough to give a "sparkle" on the tongue...? Cask beers have a short "life" due yo this - as opposdd to keg. I'm sure someone will be able to elucidate further if necessary!

Ray

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[greg l.]

I make a small quantity of red wine each year, 90L last year. For a small scale winemaker dissolved co2 is one of the biggest problems faced. Small volumes oxidise very easily so have to be kept absolutely away from air, commercial volumes welcome a small amount of oxidation in red wine. I don't have any gas exchange so small amounts of co2 stay dissolved for a long time, they affect the flavour in a big way. The combination of the sourness of the carbonic acid with the bitterness of the tannins is most unpleasant. With white wine the problem is not the same, but most white wine I drink doesn't have noticeable co2.

Surely a 220L barrel could be broken down into some 60L plastic barrels. The idea of a half full barrel makes my skin crawl.

Greg

On Saturday, 12 April 2014 02:13:17 UTC+10, Andrew Lea wrote:

[Tim]

You haven’t lived until you have used Oak, I have been drawing off from 3 barrels today, gassed them and corked down hard, will still be fine in a weeks time.

 

Tim in Dorset

 

 

From: cider-w...@googlegroups.com [mailto:cider-w...@googlegroups.com] On Behalf Of greg l.
Sent: 11 April 2014 21:36
To: cider-w...@googlegroups.com
Subject: Re: [Cider Workshop] Variable capacity tanks & IBC's

 

I make a small quantity of red wine each year, 90L last year. For a small scale winemaker dissolved co2 is one of the biggest problems faced. Small volumes oxidise very easily so have to be kept absolutely away from air, commercial volumes welcome a small amount of oxidation in red wine. I don't have any gas exchange so small amounts of co2 stay dissolved for a long time, they affect the flavour in a big way. The combination of the sourness of the carbonic acid with the bitterness of the tannins is most unpleasant. With white wine the problem is not the same, but most white wine I drink doesn't have noticeable co2.

[Miguel Pereda]

Reflections on the protection of cider :
I always bottle it around 1001-1000 of SG with the hope that the residual yeasts generate CO2 in the bottle from the interior of the liquid which naturally first be solubilized but then create a pressure above the liquid .
When bottling inevitably and logically introduce air pressurized oxygen . That oxygen initially dissolved in the cider may observe indeed sometimes becomes darker . Over time I think due to dissolved oxygen bottle , is metabolized in some way. Eventually cider gets its color and yeasts begin to generate CO2 as I said before even created an over pressure of that gas above the liquid . CO2 is also heavier than air and believe that a surface layer above the liquid will form and if the bottle is held vertically at rest and the most abundant molecules directly above the liquid will preferably CO2. Moreover, the oxygen has to diffuse through the pores of the cork and it takes time for everyone if cork quality is good.
I have found that the cider in these conditions , if microbiologically balanced , it can withstand years without raising its volatile acidity in a remarkable manner , showing that the entry of oxygen through the cork is scarce because the volatile acidity does not increase significantly .

[Alexander Peckham]

Returning to the question ... 

variable capacity tanks are fantastic if rather costly.  

 I have some Flextanks and got skins priced for these but they were very expensive so I will keep those tanks full - the price was high because the covers have to be made from a special low permeability, flexible plastic which implies that bubble wrap won't be ideal.   I have developed a system that allows me to keep some positive CO2 pressure over the cider.  This is a simple fitting in the lid.  You add CO2 though one port and a hose leads into a five foot perspex tube full of water.   As long as you keep topping up the co2 this should maintain a  head pressure of about 2 psi.

Another very good flexible volume container is the air barrier, 1000l capacity Pallecon liner which has been discussed here previously.   You can fill these and remove cider as required - the bag just shrinks to fit.  Would can also get 200l versions that fit into a drum.

I do use IBCs but don't like these - I don't remember the numbers, but they are pretty gas permeable and I don't like to keep cider in them for more that a couple of months, even when they are full.

Cheers,  Alex

[Rich Anderson]

Yes, variable tanks are costly but the trade offs are the less than desirable storage conditions in IBC’s, the need to top off and the difficulty to clean and maintain. Think of a variable tank as an investment in product quality and time. Should you decide to move on or trade up you can likely recover much of your investment in these tanks. We use both the IBC’s to haul and ferment. VT’s for long term storage, but there is no comparison when it comes to cleaning, the insurance that the tank is really clean and the product protected.

--

[lightweightmick]

Well I'm glad Miguel mentions Co2 being heavier than air!
There's a good simple experiment on You Tube that demonstates this clearly.
This is why the 'blanket effect' works surely? ...and why keeping cider active for as long as possible is a good thing.
After reading through the posts though I'm left wondering - surely Co2 won't dissolve into cider unless under pressure?
I've adapted one of those beer keg gas bottles and just give a blast into the container before refitting lid - works well for me at least at my present scale of 30 litre and 220 litre  - I aren't got room for an IBC. You'd probably need a quids worth of gas into an IBC to get a good enough layer - at least via the beer gas size - better to go for the bigger cylinders used by pubs and welders - probably what Tim uses..?

On Saturday, 12 April 2014 00:00:23 UTC+1, Miguel Pereda wrote:

Reflections on the protection of cider :

[Dick Dunn]

On Sat, Apr 12, 2014 at 05:20:24PM -0700, lightweightmick wrote:
> Well I'm glad Miguel mentions Co2 being heavier than air!

Yes, but it doesn't matter that much if you've got some CO2 and some air in
the headspace. The blanketing doesn't work because the gases mix. Try
some thought-experiments: Does the air stratify in a calm room? E.g., is
there more oxygen down low in the room because it's heavier than nitrogen?
No.

> This is why the 'blanket effect' works surely? ...and why keeping cider
> active for as long as possible is a good thing.

The blanketing works in the sense that if you introduce CO2 gently into the
headspace, it will sink (short term) and blanket the cider as you push the
air out the top. But if air is left in the headspace, it will mix in.

As for keeping cider active--yes, because you keep introducing more CO2
into the headspace and pushing O2 (if there is any) out the fermentation
lock.

If the fermenter is significanly permeable to O2, the headspace doesn't
matter that much.

> After reading through the posts though I'm left wondering - surely Co2
> won't dissolve into cider unless under pressure?

Surely it will. It does! CO2 is quite soluble in water.
(Somebody check my maths here, but I calc at STP you can get about 3/4
volume, meaning if you have CO2 above the liquid, with no more than
atmospheric pressure and room temp, a liter of liquid picks up 3/4 liter
of CO2.)

--
Dick Dunn rc...@talisman.com Hygiene, Colorado USA

[greg l.]

The whole concept of partial pressures is really quite counter-intuitive. We are used to liquids, when you mix volume a of liquid x with volume b of liquid y the final volume will be pretty much a + b. With gases the final volume will be volume a (assuming a is bigger than b). 2 gases mixed will just occupy the same volume, not the combined volume. Also if you have a headspace with no oxygen in it, the concentration gradient from the outside to the inside is very high because there is lots of oxygen in the air.  As oxygen in the headspace reacts with the cider, more oxygen is drawn in.

Greg

On Sunday, 13 April 2014 11:04:56 UTC+10, Dick wrote:

[Claude Jolicoeur]

Dick wrote:

Surely it will.  It does!  CO2 is quite soluble in water.
(Somebody check my maths here, but I calc at STP you can get about 3/4
volume, meaning if you have CO2 above the liquid, with no more than
atmospheric pressure and room temp, a liter of liquid picks up 3/4 liter
of CO2.)

I think it is more that that, Dick...
Looking at table 15.2, page 268 of The New Cider Maker's Handbook, at 0C and 1 atm CO2 partial pressure, the cider would pick 1.58 vol of CO2. At about 25C or room temperature, it would be 3/4 vol as you wrote.
Unless I made an error when I computed the data for this table...
Claude

[Wes Cherry]

Not really.   If this were the case, then you could start with a volume of gas and incrementally add a smaller volume of gas until all the gas in the universe was contained in the first volume.   

at the same pressure and temperature, Vtot = V1 + V2.   Within a constrained volume, pressure has to increase when you add the two volumes.

http://en.wikipedia.org/wiki/Amagat's_law

Also, oxygen is not preferentially drawn in via depressurization due to depletion via reaction with the liquid.  Air, as a mix of N2, O2 and a few minor gasses are drawn in equally through an airlock.    Across a membrane, diffusion will favor O2 (proportional to the partial pressure difference), but at the atomic level, that's pure statistics as there's less O2 to go out vs coming in.

-Wes

[greg l.]

I was talking in practical rather than theoretical terms. We are only dealing with 3 gases, N2, O2 and CO2. They can freely mix in the same volume without interacting.

Greg

[Cheshire Matt]

Fine! Pump in a litre of CO2 then and let the remaining 1/4 litre be above
the cider, in a higher concentration than the O2. But it'll need less that
that because there is already CO2 disolved in the cider.

Look, all this theory and counter theory stuff. If you've tried it in real
life and found it works well enough for the volumes and timescales and
effects on cider that you're actually dealing with then end of. Practice &
experience wins out every time.

[lightweightmick]

Interesting stuff Dick... 'tis good to have at least some idea of why things work...
It also explains the need to keep periodically dosing with co2 - the time factor down to how quickly that co2 is lost either above, or, into that lovely lovely stuff below that temporay 'blanket' - I'll give my half-full 220 litre ex mango chutney barrel another good blast asap! I'll have to 'cos I got nowhere else for it...
Seems the best solution for those of us who are beyond variable capacity tanks then is floating oil..? I've never tried it and can't say as I'm keen to be honest...

[Miguel Pereda]

Regardless of the CO2 contained in a bottle can preserve certain action of physically O2 diffusing from the outside, do not forget that CO2 also has bacteriostatic effect.

Greetings

[Bob Luke]

Hello Everyone-

OK, after reading everything on this thread and mulling it over for a while I think that I might really be in a tight spot when autumn arrives.

 

I am a novice to cidermaking.  Last year I made 20 gal and was thinking of upping my game tenfold this year to around 200 gal.  I am building a press and a crusher and practicing on my math skills (working through problems based on The New Cider Maker’s Handbook) which I have not used since high school chemistry class.  I am planning to ferment 30 gal batches in HDPE barrels.  I would love to rack these into 15 gal glass demijohns for secondary, but with everything else I am buying for this project the price for fourteen or so brand new demijohns seems prohibitive at the moment.

 

A funny story about this.  Last week I found a man locally, on Craigslist, who appeared to be a liquidator of hobbyist winemakers equipment.  Among other things he had a bunch of demijohns but, when I contacted him, had just sold the lot to a TV production company.  They were going to use them for a show about some guy who breaks glass with his hands.  GAAAAAAH!  Not because the guy could hurt himself, that’s his look-out, but because I needed those vessels! 

 

I talked with the people at my local brew/wine shop and they put the fear of the gods into me about oxidation!  So I thought I had found an ideal solution in 15 Gal HDPE Tight Head drums.  The tops screw down for a good seal and I had worked out a system (on paper, always suspect) to keep them topped-up and feed them CO2 from a common line at ½ lb of pressure to hold the oxygen at bay.  But then I read in Andrew Lea’s Craft Cider Making that (and Dalton’s Law has been mentioned here too-funny what you forget from your past when you don’t use it) oxygen will come through PET bottles even when the contents are under CO2 pressure. 

 

Later on this thread I read that oxygen will also enter cider stored in HDPE barrels given enough time, although they are much thicker than PET.  So whatever CO2 I put on the top would be ineffective at preventing entry of oxygen through the sides of the drum.   Wow!  I had planned to let my regular cider- and some late-season keeved cider that I wanted to try – sit in the 15 gal  drums @ 45 degrees through the winter and into the spring until I bottled.  Now I am not so sure.  That’s four months or more.  I can’t afford to lose a couple of batches! 

 

SS variable tanks look great but those are even more expensive and really not worth it unless you are working in the 50-60 gal range - at the small end!

 

My question is-do I really have to go to glass or SS in order to avoid the risk of spoiling everything?

 

Thanks to all for your consideration.

 

/bob luke

Catskill, NY

---

Date: Sun, 13 Apr 2014 18:02:30 -0700
From: m.l.w...@btopenworld.com
To: cider-w...@googlegroups.com
Subject: Re: [Cider Workshop] Re: Variable capacity tanks & IBC's

[Rich Anderson]

You might consider purchasing some used 15 gallon stainless beer kegs and having a welder rework the ball valve to a tri clamp fitting or equivalent. These are heavy, 150 pounds plus and may want to reconsider the variable capacity tank instead.

 

[Wes Cherry]

Stpats sells a $2 gasket that let's you use a standard keg with 2" triclover fittings. No welding required.   Be careful removing the spear. If there pressure in the keg the spear can go flying when you remove the retaining ring.

http://stpats.com/oakbarrels.htm

-Wes

Sent from my iPad

On Apr 23, 2014, at 7:54 PM, "Rich Anderson" <rhand...@centurytel.net> wrote:

You might consider purchasing some used 15 gallon stainless beer kegs and having a welder rework the ball valve to a tri clamp fitting or equivalent. These are heavy, 150 pounds plus and may want to reconsider the variable capacity tank instead.

 

--

[greg l.]

One alternative is to ferment at slightly higher temperatures and get the fermentation finished a bit earlier. If you can heat your cider shed a little it will help to get the cider finished earlier, and shouldn't be detrimental to quality. Most early ripening cider varieties go through fermentation faster.

Greg

[Andrew Lea]

On 24/04/2014 02:07, Bob Luke wrote:

> I had planned to let
> my regular cider- and some late-season keeved cider that I wanted to try

> – sit in the 15 galdrums @ 45 degrees through the winter and into the

> spring until I bottled.Now I am not so sure.That’s four months or more.I
> can’t afford to lose a couple of batches!
>

> My question is-do I really have to go to glass or SS in order to avoid
> the risk of spoiling everything?

No of course not. You are forgetting two things -

1. Wall thickness. Four months in a proper HDPE / LDPE tank like these
(http://www.speidel-behaelter.de/form/foreign/enghausm.pdf page 10) with
wall thickness of around 6 mm is no problem. I do this all the time. It
takes 4 months for me to do my fermentations at ambient UK winter
temperature (I'm not one of your 2-week turnaround merchants), and the
ciders then sit under airlock another few months in these vessels in
spring after racking, before final blending and storage in SS. If a
small amount of yeast remains in the vessel, it will have the effect of
scavenging traces of oxygen too.

2. Surface area to volume effects. You say you want to make 200 gallons
split into 15 gallon batches. If they are all the same blend, that makes
no sense because it entails 14 separate containers, hence far too much
handling and unfavourable SA/V ratio. Try to cut that down considerably
(ideally just 2 or 3 active containers plus one empty for racking).

Of course variable capacity SS is the tops. But you can live without it
if you're canny.

[Bob Luke]

Thank you everyone for your replies to my query. I have been away from home with no computer access so when I get back next week I will research the suggestions.

Wes and Rich-I am not sure what used stainless kegs cost. As you mention, the weight could also be a factor. I will look into it.

Greg-for me a warmer environment/faster fermentation won't work. That's what I did the first time and, although the cider was good, I want to experiment with a deliberately slower process and see what differences are present in my end product.

Andrew-again. when I can get to a desktop computer with an actual monitor instead of this blasted phone with a tiny screen I will check out the Speidel suggestion. As for the breakdowns of the 200 gallons, some are deliberate and others arbitrary. Out of the 200g whole I wish to make 6 different 30g batches-earlier and late harvest, pitched and wild yeast, keeved-as well as a few 5g flavor experiments. the breakdown into 15g for
secondary was arbitrary, made only to accommodate the 15g glass demijohns. If I can keep them in 30g HDPE as you suggest I will certainly do so. The fact that you have had success with your process heartens me.

Thanks again All for your help. This a great forum and a fantastic resource. I am glad that I discovered it!

/bob

Sent from my iPhone. Please excuse the typos.

On Apr 24, 2014, at 4:33 AM, Andrew Lea <y...@cider.f9.co.uk> wrote:

> On 24/04/2014 02:07, Bob Luke wrote:
>
>> I had planned to let
>> my regular cider- and some late-season keeved cider that I wanted to try

>> - sit in the 15 galdrums @ 45 degrees through the winter and into the

[Rich Anderson]

We purchased 6 or 8 used 15gallon kegs several years ago from a Seattle
brewery for $10 each, if I understand the fittings displayed on St. Pats, it
looks like they started with a standard 2" tri end cap, that a gasket and
clamp would run about $10-$12. I checked ours and indeed a 2" cap, clamp and
gasket fit the keg flange however the finish on the keg flange is missing
the gasket grove which tri clamp flanges have. Still look like it would work
ok. Not sure how you remove the ball valve but suspect it is held in with
some sort of ring clamp or nut.