2/2.5 gallon all grain

[kane]

Hey,

Well after recently getting back into brewing using extract, i'm now thinking of heading into all grain territoy with batch sparging.

I'm hoping to do small batches of around 2/2.5 gallons, simply because i already have a pan that fits 14L/3gallons.
I know for the same amount of effort i could brew 5 gallons, but for myself i'd prefer to have a few more small batches on the go rather than a couple of large ones which i may not even like.

I found this http://www.camping-online.co.uk/igloo-c ... r-jug.html (2 US gallons)
Which i think i could easily convert into a mash tun like other people have done with the larger cooler boxes and some braided stainless steel.

Then using this formula i found on another post:

Grain [kg] x Stiffness [l/kg] + Grain [kg] x water absorbed per kg

Assume water absorbed to be 0.67 and Stiffness 2.4

I calculated that the 7.7 litre cooler could fit about 2.4kg of grain, which is easily large enough for most 5 gallon recipes halved. For recipes which require an even larger amount of grain i could either reduce the brew size to 2gallons or convert to using fly sparging?
The reason for not buying a larger cooler is that i thought reducing the amount of head space would reduce heat loss?

Does this seem like a sensible thing to do? or have i missed out some important points in my planning?

Cheers guys
Kane

[gnorwebthgimi]

Hi Kane

To be honest I would go with the larger cooler.

Yes the larger space will PROBABLY increase the amount of heat loss (but this should be slight) and you may need a slightly higher strike temperature. You can compensate by preheating the mash tun, which should sort the issue out entirely but it probably won't because:

I would say the bigger issue you will have is with mashing smaller quantities. You will get much more heat loss due to the increased surface area (proportionally) of a smaller amount of grain. There is little you can do to compensate for this except maybe go mad with insulation (such as putting the mash tun in a blanket).

You WILL undoubtedly be converted to All Grain and you will need to buy another cool box if you get the smaller one. Save yourself the extra expense.

I take it you will be bottling? you might get oxidation issues with a keg using small quantities (due to dead space again). Although you might be able to get around this with co2 blanketing the keg.

What about hops? how will you buy a small enough amount of hops for such a small batch?

Read the recent thread about top tips for going AG too.

viewtopic.php?f=2&t=35739

[bosium]

I would really like the 5-gallon igloo on that site, but not for £50. I am also trying to build a smaller brewery - my mash tun is a bit big for just 2 or 3kg of grain as the grain bed is a little shallow. The 5-gallon cooler on the site would be perfect tho as it's deeper rather than long, so would still work really well with just 2 or 3 kg of grain.

I'd definitely go for the 5-gallon cooler iiwy..

[Kev888]

Hi,

I think you may have missed out something from your calculations; working backwards from a 14L at start of the boil I get about 6L of liquor for the mash plus 4.4L top up for the first batch = 10.4L. Then you need to factor in that the grain itself needs some space (on top of what it absorbes), at say 0.7L per Kg, which brings the total to over 12L or 3 gallonsUS of space for each batch. Even assuming no losses to dead space hops etc its still over that small cool box if you want to near-fill your boiling pot. Theres a useful batch sparging calculator here if you've not seen it - its the total water for batch #1 thats of interest in terms of max liquor, and then add on 0.7L per kg for the grain itself to determine overall capacity needed.

Maybe I got something wrong - it certainly wouldn't be a first.. To be frank though, I'd just go for a normal sized MT; I regret the slightly mean size of mine and it causes no end of aggro - having to top up and do partial grain to get decent strengths or volumes and having to brew little but frequently even if there isn't time. You don't save much on time or effort with smaller kit and I don't think head room is a real issue within reason - air neither absorbes much heat or transmits it to the extra side wall area very well compared to the liquor. If you pre-warm the tub and maybe add a sleeping bag or something then I can't see it being anything you can't easily ballance with the right strike temperature.

I can see the benefit of a small system as an addition to a normal sized one, but personally I'd find it too restrictive as the only one.

Cheers
kev

[WishboneBrewery]

I use an insulated 15litre bucket as a tun for a 12litre brew length.
WOrks a treat check out my blog on the equipment link for pictures.

[Brotherton Lad]

I'd go for a larger mash tun rather than restricting your future options. The extra head space won't make any significant difference. Pre-heat the tun with water that's too hot ((about 80 C), let it fall to your correct strike temperature (about 74 C in my set-up), put the lid on and wrap it up well. Mine stands on a couple of newspapers with an old sleeping bag round it.

[danbrew]

I use a 10l coolbox that I picked up for a fiver from go outdoors. I make 2 gallon (9litres) and have never had any problems with space.

I go with the method of every kilo of grain you want to mash needs approx 3.6l of space in the mash tun.

BUT about your rationale for a smaller brew length, if I was you I would think about how much beer you consume combined with how often you can (practicaly) brew. Those two factors should determine the amount of beer you should be brewing at each session. I might only have a couple of bottles a week so a brew length of 16 pints means I only brew every two months.

Think about demand first then consider the supply, not the other way round.

[bosium]

Honestly, go for the 5-gallon. Reason being - if you want to mash up to say 3kg of grain for a small batch - you can dough in with 3L per KG (9L), then mash out with another 9L of hot water to fill your MLT and then you can run off without having to sparge. I do this on small batches and it's great - I still get 72% efficiency (mash out helps), the wort is of a higher quality than usual (no sparge) and it saves quite a bit of time.

It also has the added benefit in that you can switch to sparging and do bigger batches using the same equipment.

[danbrew]

...and if you are worried about heat loss through dead space you can pack this out with rectangular pieces of camping mat. I put a layer of foil on top of the mash then pack out with camping mat now and my heat loss has reduced...

[kane]

Thanks for all your replies.

This has definitley given me something to think about, it seems like im now moving towards getting a 5gallon cooler.
My extract brew has been in the bottle two weeks and im already nearly half way through it so maybe larger batches are required .

I think the maximum i would ever want to brew would be 5 gallons, and the reason for suggesting a small brew size was mainly a lack of a boiler (and wasting 5 gallons of beer if it didnt turn out right ).
However it seems the boiler can easily be made from a bucket and kettle elements so i dont think that would be a problem anymore.

I also calculated the difference in price between brewing a 23L and 9L batch, and it is fairly minimal (due to having to buy hops in vacuum packs etc.)

So i think the plan will be: carry on with another extract brew, then when i have all the equipment together do a full 5gallon AG batch.

Now the only problem will be where to store all those bottles ....... lol

Cheers
Kane