Batch size

[moto748]

Another quick question, please!

Scanning through the very interesting recipes posted here, most of them quote a 'batch size', say 10 litres or 22 litres or whatever.

Is this the total amount of water used, including sparging? Or the volume of beer you end up with when pitching the yeast? Or something else?

 

[GeorgieV]

I believe this is the amount that goes into the FV. The calculators use it for predicting the original gravity.

 

[Galena]

It 'usually' refers to the total amount in the FV after grain absorbtion, boil-off and trub loss is taken into account, and using my last recipe with Brewfather software as an example.

Batch Volume 21L

consisting of:
Mash Volume 13.65L
Sparge 16.66L
Total Water 30.31?

Although I do round those numbers up to the nearest Litre

 

[chrisb8]

Batch size is the volume of wort you have in the fermenter before pitching the yeast. Bear in mind that the fermenter will end up with a layer of trub which will reduce the volume of beer you eventually have to bottle/keg.

 

[moto748]

I see (I think!). So in Galena's example, about 30 litres of water are required to produce a nominal 21 litres, ie, perhaps 40 bottles approx.

The recipe I was actually looking at was Clibit's Fisherman's Stout, which quotes a 10 litre batch size, so perhaps I should start with around 15 water total. I'm a Guinness drinker myself, and would love to make a decent stout (my ongoing efforts at parsnip stout are still at the "needs further work" stage! ).

Thanks,guys.

 

[Galena]

You need to calculate it, or use software, grain will absorb around 1 litre /Kg and the boil off rate depends on your equipment which you can test by measuring and boiling for an hour. There is no need to guess, try learning to use Brewfather, its free and does all the calculations for you after a bit of a learning curve.

Not sure about parsnips but Greg Hughes book has a lovely Oatmeal stout recipe in it, one of my favourites.

 

[Rento]

You need to calculate it, or use software, grain will absorb around 3 litres /Kg and the boil.........

Can I jump in with a query as I’m about to do my first BIAB.....how much should you factor in for grain absorption? I read 1 litre per kilo of grain for loss in the mash somewhere. Is that a good assumption? I“m doing a small 9-10 litre batch so only going to use 2.2kg of grain, so was thinking something like:

12l mash water
3l sparge in bag into kettle after 1hr
once I clear bag I‘ll have approx 13l of wort (2l loss)
30 minute boil will loose me about 1.5l (from testing with water)
loose about 1l to trub at bottom of kettle
so 10.5ish to FV
leaving around 9.5 to keg After fermentation.

is that reasonable?

Sorry moving off topic.

Thanks

R

 

[moto748]

Thanks, Galena, I see. I'm no technophobe, and I make my living with software, but I don't really want to download stuff and 'join' anything regarding beer-making. I had a look at the Brewfather app, and it all looks very clever, but, I think, largely aimed at people with more equipment and rather more sophisticated methods than mine.

 

[Galena]

Can I jump in with a query as I’m about to do my first BIAB.....how much should you factor in for grain absorption? I read 1 litre per kilo of grain for loss in the mash somewhere. Is that a good assumption? I“m doing a small 9-10 litre batch so only going to use 2.2kg of grain, so was thinking something like:

12l mash water
3l sparge in bag into kettle after 1hr
once I clear bag I‘ll have approx 13l of wort (2l loss)
30 minute boil will loose me about 1.5l (from testing with water)
loose about 1l to trub at bottom of kettle
so 10.5ish to FV
leaving around 9.5 to keg After fermentation.

is that reasonable?

Sorry moving off topic.

Thanks

R

Yes sorry, just realised I put 3l/kg for absorption which is nonsense, edited that now as it should have said 1L/Kg, (approx) the 3 litres was boil off rate.
Going by my setup if I was going for a 10 liter batch (in FV) with 2.2Kgs malt would give the following
8L mash water
8.55l sparge water
16.55L Total Water

That is based on a 60 minute boil with 3litres loss so your 30 min 1.5litres is somewhere in the right area.

 

[Galena]

Thanks, Galena, I see. I'm no technophobe, and I make my living with software, but I don't really want to download stuff and 'join' anything regarding beer-making. I had a look at the Brewfather app, and it all looks very clever, but, I think, largely aimed at people with more equipment and rather more sophisticated methods than mine.

Each to their own, but all Brewfather does is help you create, or download others recipes and calculates quantities etc, the equipment matters little.

 

[GeorgieV]

@Rento ,
Your line of thought regarding the water volume calculation seems reasonable in general. I would only comment on the ratio between the strike (mash) water volume and the sparge volume. My understanding is that if you have larger proportion in the mash and smaller sparge volume, that may affect your efficiency. I read about the full volume mash (i.e. no sparging) where it is recommended the grain bill to be increased by 20 % in order to compensate for the lower efficiency.
I'm rather curious why you are aiming at 30 min boil as most of the recipes are calling for either 60 or 90 minutes?

@moto748, I totally understand you. I also get annoyed by all that "download and register" s***t. Anyway, you can find a lot of useful calculators in the calculator section of the forum (see the top of the page).

 

[Drunkula]

I had a look at the Brewfather app, and it all looks very clever, but, I think, largely aimed at people with more equipment and rather more sophisticated methods than mine.

I had absolutely sod all apart from stuff in the house when I started doing all grain. Get the test version of BeerSmith and just fannying about with it, adding grains and looking at the figures in how it changes the abv and the water needed will teach you loads. And you'll need to learn what efficiency you're getting with your setup so you can make recipes you might find have the expected outcome.

You don't sound like an old fart so don't hinder yourself by rejecting brewing software, star san or still thinking pressure barrels are a good idea.

 

[moto748]

Well I'm an engineer by trade, but I also recognise that the wonders of the world, from the Empire State Building to the Eiffel Tower to the Hanging Gardens of Babylon, were all created without the aid of software. Just like people have been making beer for millennia. And yes, it is, partly (but not just that!), the 'download and register' aspect that I dislike; everyone wants a piece of you these days. But that's the world we live in.

For my needs, Galena's comments upthread about grain absorption would probably give me a good enough guide. In fact, to put an engineer's twist on it, let me put it this way: one long-standing adage is that you don't use approximate values in your input data, and then give the answer to three places of decimals! Software (any software) gives the impression of precision, because you input your data and hit Return and there's the answer, but of course it is only as accurate in the input data. So because my methods are approximate, I wouldn't consider it necessary, or even useful, to run tests to check my boil-off rate. If I was going to attempt calculation, some generic value would surely do. The idea of making beer as it was made, say a hundred years ago or so, is quite appealing.

I don't use pressure barrels!

And thanks to you all for taking the trouble to contribute; it is much appreciated!

 

[Rento]

I wasn‘t Initially going to sparge at all, but thought it’ll help a little with the efficiency, I generally like my beer low abv anyway so not that bothered so may just go full volume. The 30 minutes comes from research, as for a single hop, I read that all you need to do is up the hop Volume and boil for 30. My interest in BIAB is partly to get to know hop flavours so intend doing quite a few 10l SMASH type recipes to both learn the method and learn about the hops.

As a keen gardener I’m also thinking I’ll try growing my own hops when I find out what I like.

@Rento ,

I'm rather curious why you are aiming at 30 min boil as most of the recipes are calling for either 60 or 90 minutes?