Biab Ag 30l Urn?

[Cronessa]

Hi All,.

I am currently saving for a mash tun esky conversion kit from Beerbelly, but I just happened to come across a near new 30L urn at the local trash and treasure last Sunday for the princely sum of $20 and thought it may be a good chance to try AG sooner than planned. I planned to bring the water up to strike temperature in the urn, then transfer the water into an esky lined with swiss voille for 90 minutes and then transfer the liquid back to the urn for boiling and hop addition.

The more I read, the more I am confused about the water volume required for a BIAB AG.

I'm hoping to produce enough wort for a 20-23L batch. To prevent boil overs (if its anything like using DME) I imagine I can only get away with a starting boil volume of around 25L.

From what I can gather, the water required is determined by the water lost from boiling (around 5L per hour), the grain to water ratio and the water retained by the grain bill?

Most 20-23L AG batches call for around 5kg of grain. Would it be possible to use this amount of grain in a smaller water volume (say 25L) and then bring the final volume up to 20-23L by adding water to the fermenter?

Apologies if I have confused terminology etc, I'm still a newb!

Cheers

 

[seemax]

Start with your volume into the fermentor and work backwards.

In a nutshell your losses will be...

MASH/LAUTER
-grain absorption (rough guess 0.7L /kg )
-mash tun dead space (0.5 - 1.0L)

BOIL
-evaporation (10% guess)
-trub loss (1-2L)
-cooling volume loss (4%)

So... say you want 23L into the fermentor, your preboil volume will be

23 + 3 (evap) + 1 (trub) + 1.5 (cool) = 28.5L

Then your mash/sparge volume is then 28.5 + 3.5 (grain) + 1 (dead space) = 33L

In your case, your mash in will be 25L ... on a separate pot get 8L (33-25) up to sparge temp... drain your first runnings into the urn, pour the sparge water into the esky, stir grains, wait 5mins, drain the 2nd runnings into urn.

The only catch is your urn is 30L

Minimise your losses somewhere, brew a lower OG beer... or reduce your batch size. Naturally adjust my assumptions to suit your setup, or use Beersmith to do all the hard work!

 

[Mobbee007]

Minimise your losses somewhere, brew a lower OG beer... or reduce your batch size. Naturally adjust my assumptions to suit your setup, or use Beersmith to do all the hard work!

cut your grain bill and top up with extract?
I also have a 30L urn and if you're boiling 25L keep a close eye on it for boil overs
( but to be fair i'm also a newb!)

 

[Cronessa]

cut your grain bill and top up with extract?

Thank you for the info guys!

What is the compromise in the final product (flavour etc) between an AG and a Partial?

I was kind of hoping that I could make a 'concentrate' by using less water and bringing it up to volume in the fermenter. What's the limiting factor in this? The grain to water ratio? Does the volume of water reach saturation point?

I'm having a play around with beer smith at the moment, its a bit daunting!

 

[seemax]

There is no hard and fast rule for comparing AG with partials.

The key is process... sanitation, fermentation temperature, yeast type/health/quanity, etc.

Take for example a pale ale... assuming the same yeast and hops, using a 1.5kg can of LME to replace say 2.5kg or pale malt would be perfectly ok. In fact I would suspect only a seasoned taster would pick up the difference.

The only downside to malt extract is attenuation. Dry extract appears to be worse than liquid. Expect higher FG's.

What sort of styles do you want to brew?

 

[Mobbee007]

There is no hard and fast rule for comparing AG with partials.

The key is process... sanitation, fermentation temperature, yeast type/health/quanity, etc.

Take for example a pale ale... assuming the same yeast and hops, using a 1.5kg can of LME to replace say 2.5kg or pale malt would be perfectly ok. In fact I would suspect only a seasoned taster would pick up the difference.

The only downside to malt extract is attenuation. Dry extract appears to be worse than liquid. Expect higher FG's.

What sort of styles do you want to brew?

from all i've read and been told by mates it's very hard to pick a partial but a general rule of thumb is follow the rule of 2-1 malt-dex so you don't get such a sweet final product
hope I remembered that right and am not giving you the wrong info (can anyone correct me?)
beersmith is awesome after playing with it for awhile IMHO

 

[big78sam]

I have a 30L urn and have no problems with getting a 20L batch. 5kg of grain is comfortable, I have used more though. I can't remember who initially posted this but it is what I do.

View attachment Smaller_Urn_2V_BIAB.doc

This requires mashing in the urn, with an extra dunk sparge in an esky to assist get the final volume to 23L. The good part of BIAB is that the mash and boil all occur in the same vessel, ie the urn. The smaller urn means a second vessel is required (i use an esky) for the dunk sparge.

I'd recommend you read the sticky BIAB in an urn thread. Bribie's description are really helpful.

Just give it a go. You'll find it's easier than you think!

 

[Mobbee007]

I'd recommend you read the sticky BIAB in an urn thread. Bribie's description are really helpful.

was just about to recommend that myself!
cheers

 

[Cronessa]

What sort of styles do you want to brew?

Eventually, I'd like to try every style

I guess the first style I would try would be an American Pale Ale to compare it to the 'kits & bits' version I did using:

Coopers Pale Ale Kit
1kg LDME
350g Dextrose
150g Maltodextrine
400g Bairds Pale Crystal
Cascade Hops 15g at 15 mins, 0 mins and 20g at 4 days fermentation.
Coopers Pale Ale Re-cultured yeast

I'd also planning a Leffe Blonde clone and my first lager is also on the cards (now that I have a second fridge that can hold 10C).

 

[RdeVjun]

Have you seen BribieG's tutorial? I can recommend it.

Now, there's not really any practical obstacles in doing under- volume boils for a given grainbill, however it is a challenge for novices. I can assure you that I regularly make 21- 23L BIAB batches in a 19L stockpot, so I know it can be done in a 30L for sure. However, if you're just trying to get a feel for the equipment, I would stick to scaling back a recipe first and it will take a few goes at it to get a handle on it. The whole thing can be pretty hair- raising with uncertainty running riot if you've not seen it before, so I'd keep it as simple as possible and accept a lower volume into the fermenter for now.
The things you'll most probably need to do later when attempting this are i) dunk sparge/ mashout and ii) post- boil dilution, while if you brew adjunct- friendly styles (ESB for instance) then iii) some of the extra points are more easily gained (sugar). This recipe of mine is one such style (mash 65C BTW).

In answer to your second post, not much compromise at all, even 50% of fermentables from mashing grain yourself should trick up some extract in a pretty phenomenal way, that's how I'd look at it.

As above, post- boil dilution is routine for me. The limiting factors are how much grain you mash with and your efficiency, initially I'd be accepting low efficiency until you're familiar with what is in the end quite simple and rudimentary equipment, albeit all that you need to produce excellent beers once you find your way around it. :icon_cheers:

Edit: Dang!

Edit2: An esky is fine for a sparge vessel, or could even use a plain old bucket, but usually you're trying to mashout at the same time, so pay close attention to temperature (usually around 75C). I usually sparge with 6L of 85C slightly acidified water (citric acid or 5.2) in a bucket.

 

[Nick JD]

I can make a 23L AG batch of 5% beer with a 19L pot.

30L ... I could outdo Carlton United Breweries!

Mash for a high OG and then dilute in the fermenter. Easy.

EDIT: SNAP!

 

[big78sam]

It's too late to edit my last post... try this thread as well. It discusses the limitations of a 30L urn.

http://www.aussiehomebrewer.com/forum//ind...935&hl=ebay

I am no expert. I've only done about 6 AGs in a 30L urn but if you want PM me and I can give you my number if you are stuck on brew day. Where are you located?

 

[Cronessa]

I have a 30L urn and have no problems with getting a 20L batch. 5kg of grain is comfortable, I have used more though. I can't remember who initially posted this but it is what I do.

This requires mashing in the urn, with an extra dunk sparge in an esky to assist get the final volume to 23L. The good part of BIAB is that the mash and boil all occur in the same vessel, ie the urn. The smaller urn means a second vessel is required (i use an esky) for the dunk sparge.

I'd recommend you read the sticky BIAB in an urn thread. Bribie's description are really helpful.

Just give it a go. You'll find it's easier than you think!

Thanks for that (and all other posts)! So it looks like I will be able to get away with it.

Yes, Bribie's sticky is fantastic. I've read and re-read it seven or eight times.

It's too late to edit my last post... try this thread as well. It discusses the limitations of a 30L urn.

http://www.aussiehomebrewer.com/forum//ind...935&hl=ebay

I am no expert. I've only done about 6 AGs in a 30L urn but if you want PM me and I can give you my number if you are stuck on brew day. Where are you located?

I'm in Adelaide, thanks for the offer!

 

[Cronessa]

For post-boil dilution, is it just a matter of starting out with less water than is recommended (therefore ending up with a higher OG) and then diluting with water in the fermenter?

For example, if I'm following a recipe to make a 20L batch and the BIAB procedure calls for 30L water ideally, can I just mash the same amount of grain in say 23L of water and then add back up to 20L for water losses?

If not I will give the protocol mentioned in the doc file above a go, but I'd rather try and keep it as simple as possible (whilst still producing a 'full' batch).

I apologise for the (probably obvious) questions, still trying to get my head around it all...

 

[Nick JD]

For example, if I'm following a recipe to make a 20L batch and the BIAB procedure calls for 30L water ideally, can I just mash the same amount of grain in say 23L of water and then add back up to 20L for water losses?

Sure can. It's always easier to add water than to remove it.

 

[Thirsty Boy]

As much as I like BIAB ... if you are set on going with an eski conversion anyway, then there is no reason to learn things twice. Skip the BIAB part altogether.

Whatever your plans were for your eski based system... just do that. The only difference being that you have some voile in your mash tun instead of the false bottom you will eventually have. Apart from that, all the same.

I'd forget about BIAB - your are going to be a mash tun brewer, so learn about mash tun brewing. Read up on simple batch sparging (here's a good primer if you haven't got much info yet (http://hbd.org/cascade/dennybrew/) - then batch sparge. The fact that you are starting out with a length of voil instead of a false bottom should make very little difference to the process.

If you dead set want to have a quick easy crack at BIAB before you hit the mash tun... just skip the dilution and doing part in the eski, part in the kettle. Make a little less beer. Its a quick brew before all your kit arrives... make your life easy and settle for 15-17L. So everything fits in your pot all at once, no dilution, no sparging.. just stock standard BIAB. Then when your stuff arrives you can forget you ever sullied yourself with BIAB and there isn't too much great beer hanging around to remind you about it.

edit - It was me who wrote that document that big78sam posted. Method specifically designed to work with a 30L urn and eski combination - full wort volume at start of boil so there is no need for dilution or altering your hop calculations.

 

[mxd]

you could do a 2V + Bucket type BIAB.

If you have an esky that will hold heated water and you can open the drain plug you could try something like the following.

Assumptions - 6 kg grain, 66 Mash

1 place 30 ltrs of water in urn.
Heat Water to 75 degrees
Put a couple of litres of boiling water in esky (to heat esky up)
empty water from esky
place BIAB bag in esky
place 15 ltrs (2.5 x grain weight) into esky
Fill kettle with water
place grain in bag in esky
give grain a good mix
Check temperature of esky
Adjust with more hot or cold water (upto 2 litres)
Mash
Cover up and leave it alone for 60 or so minutes
Keep kettle at 75 Degrees
now mash out and batch sparge (lots of info around)
Keep wort in cube or fermenter untlil you've used all the water in the kettle
When kettle empty move wort to kettle and boil (for me I need around 28 ltrs pre boil for 20 litres wort post boil (evap 5, trub 3 -4)
Boil for an hour adding hops
Put in cube (for no chill)

N.B haven't done this yet but been trying to for a cople of weeks

plenty of people here will correct me and give you the right advise but the above should lead you in a way that should work.

cheers
Matt

 

[Bribie G]

That sounds similar to what I did in the UK thirty years ago with my Bruheat Boiler - the problem with Bruheats is that they are only around 23 litres, so you can use it as a mash tun or as a HLT or as a boiler, but you can't use it in the same way as a full-volume BIAB in a 40L urn. I had to extend the process with one or two extra vessels (which aren't expensive in themselves).

I used it as a mash tun, and also bought a cheap esky so I've tried both methods. My most successful procedure was very similar to the official Bruheat method here.

If you read this, you can sub "30L Urn" for "Bruheat". Now have you spotted the elephant in the room here? Yup it doesn't say where the sparge liquor comes from. So what I used to do was prepare a batch of sparge liquor in the Bruheat upfront at around 80 degrees, run it into the esky or (perhaps more effective) run into a bucket type fermenter with a tap and just run electric jugs of it off now and again, boil and add back to the vessel to keep it hot for an hour while the mash proceeded. With a SS urn I'd just use passive lagging with a doonah or sleeping bags for the hour's mash and not power it up, so no problems with hotspots or burning.

Edit: grammmmrrr

Also, if you collect the runnings in a couple of smaller cubes or buckets it's less of a backstrain lifting the sweet wort up to pour it back into the urn when it becomes the kettle.

 

[Cronessa]

Thanks for the great replies! I'm always astounded by the level of help offered on this forum, hopefully I can get to the stage where I can give back at some stage!

There seems to be some difference of opinion on whether post-boil dilution is a suitable option? What would be the advantages of using a secondary vessel (and using the original volume of water) over post-boil dilution (or even adding hot water pre-boil)?

I know I shouldn't be choosing a procedure just because it is the easiest, but I'm not sure what the disadvantages are of choosing a 20L batch recipe, starting off with 23L of water in the Urn, using that to mash out in, bringing it up to boil and add hops, and then topping up with hot water up to 20L.

 

[mxd]

I think the biggest advantage of doing a 15 ltr type BIAB is

1) as you have not done a AG of yet, you will make mistakes so try and make it as simple and as similar as you would normally do.
2) you will bugger something up that may or may not make drinkable beer (my 3rd batch, I think temp too high so lots of un-fermentable sugars)
3) you don't know your setup, evaporation, trub loss, efficiency etc..
4) make slab type batches so when you get all your gear you know what will be a standard brew.

If you try to do a 15 ltr that you dilute then you need the wort around 1070, so you'll require 7 kg or so of grain, then this will soak up more water than you thought about, be heavier to pull out, just cause more heartache (this one I have been involved with )