Sparge Water Temperature

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Jolls

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Hi Team,
I am about to have a crack at my first AG brew - an Australian Ale. I have searched the forum but could not locate the answer to my question. I trust this hasn't been answered a million times before!

I am making a 19 litre wort for kegging and have used Brewers Friend to figure that I need 5.4 litres of strike water at 67 C and 23.9 litres at 76 C for sparging. My lautering tun is a 25 litre square esky with a manifold made from brsided hose with the rubber removed in an oval manifold ri=unning to a ball valve. I unnderstand that the temperatures are at the grain; however, given this is my first try and I have no data to figure out my heat losses I need a start pointto work from. I estimate maybe a 5 degree heat loss between the HLT and the grain - but this is a SWAG. Can anyone give me a guide as to what the recommeded temperatures should be in the HLT? The HLT is likely to be another 25 or so litre esky with a silicone hose between the two. I have yet to build the sparge arm but was thinking a simple T in 1/2 inch copper with some 1.5mm holes drilled in down each side at around 30 degrees from vertical. Any other guideance on DIY sparge arms would be great too!
Thanks in advance for the advice.
Cheers n Beers
Jolls
 

MHB

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Something is very wrong with your calculations!
It takes at least twice the mass (L) of strike water to grain just to cover all the grain, 3-4 Liquor to Grist (L:G Liquor is what we call brewing water and the L:G is the common way to express your water to grain ratio). So you will need a minimum of double your mass of grain, most people use a lot more.
Somewhere around 3.75:1 is about half your water for mash in and half for sparging.
Sparge water shouldn’t be hotter than 80oC, if it is it will tend to pull a lot of harsh tannins out of the grain husks and you will taste that in your beer.

Let us know how much grain you are planning to use and we can help nail your numbers.
Mark
 

Jolls

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Hi Mark

Thanks for picking this up. The grain bill is 3.5kg; comprising:

3 kg Ale malt
0.4kg Flaked Wheat
0.1kg Munich Malt and
8 grams of Roasted Barley

There is 30g PoR Hops, 1 tsp of Koppafloc and the yeast is Safale US 05

The Mash Guidelines (on the recipe builder) are as I stated above - 5.4 litres of strike water at 67 C and 23.9 litres at 76 C for sparging. However the water calculator comes up with the following. Why the difference between strike and sparge water volumes between the two?

Total mash water needed32.3
Strike water volume at mash thickness of 1.5 L/kg5.3
Grain absorption losses-1.8
Remaining sparge water volume27
Mash Lauter Tun losses-1
Amount going into kettle29.5
Boil off losses-6
Hops absorption losses-4.5
Amount going into fermentor19
The starting mash thickness is quoted as an L:G of 1.5:1 which is well under the L:G ratio of 3.75:1 you provided above.

If I have interpreted your post correctly the figures should be an L:G of something like 13.125:3.5 for strike and the same for sparge - this is more than double the strike water butvonly half the sparge Brewers Friend calculated. I am now officially confused!

In relation to the water temperature. I was aware of the tannin issue. For planning I am thinking that I should heat the strike water heated to 73 C to have 67 C at the grain (allowing 5 degress for losses in transfer and heating the grain from room temperature). As the grain is already heated do I need to have the sparge water a couple fo degrees above to account for losses (78 C) or am I overthinking it and just heat the sparge water to 76 C and crack on?

Sorry if I have completely missed the point - I thought the software would have the water calcs all sorted.

Regards
Jolls
 

raybies

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I don't use any calculators... I wing pretty much everything, but I'm with @MHB on this, I think you need more strike. I've been using a ratio of about 3(strike):2(sparge) usually for a 23L batch I will have ~5kg grain, 15L strike and 10L sparge. Apart from one batch where I totally messed up the mill, I've been getting great yields. I usually need to add water during the sparge to get to 26~27L this varies from 3~5L batch to batch and I add it with the garden hose.

For sparge temp. I almost boil (<90c) a 10L pot, slowly pour it in, then use a garden hose (15~20c) to finish. The cold water also helps me press the mash. Some of the variability comes from how much I press the mash... because some say you should/not... I'm leaning towards should.
 

MHB

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Just doing a quick finger count I get an OG of ~1.043 in the fermenter, is that close to what you were aiming at?

I dont use brewing software and arent all that familiar with Brewers Friend. There is a good chance that the settings you have put in aren’t all they could be.
As above it takes around 2L of water just to cover 1kg of malt. You would only mash in that thick if you were going to use hot (boiling) water to do a step mash. Low L:G mashes favour the enzymes that degrade Protein and Glucans and tend to be lower temperature mash steps in the 40-55oC range. You then add hot water to come up to your Amylase temperature (60-75oC) probably close to 67oC as its a good balance between Alpha and Beta Amylase activity to make sugars.

Standard number for grain water absorption is ~0.9L/kg so for 3.5kg you would expect to lose 3.15L of water. The loss (wort left in the mash tun) you need to measure.
Boil off should be in the close order of 10% total, so 10% if you are boiling for 1 hour, if you have ~30L going to the kettle you would expect to lose 3L to boil. What you leave in the kettle should be in the 5-10% of the after boil volume, so another 1.5-3L
I can absolutely guarantee you that 30g of POR can’t absorb 4.5L of water

If we take a look at the standard Strike Water Equation
Strike Water Temperature = {(0.4*grain weight)+strike water weigh)]*rest temp-(0.4grain weight*grain temp)/water weight.
You have 3.5kg of grain if you mashed in with 5.3kg (L) of water, and the grain is at ambient say 28oC and you want to mash at say 67oC.
We shove all that into the equation
SWT = [((0.4*3.5)+5.3)*67]-(0.4*28)/5.3 = 77.3oC that would be your strike temperature.

I think you need to go through your settings very carefully.
Mark
 

Jolls

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Thanks Raybies and Mark

OG is calculated at 1.041 and FG 1.007

Not sure of the value of the software then - I jumped on the band wagon as I expected that it would be a great guide until I learnt the basics a little better, I like your rule of thumb and detailed calcs much better. I will re-read the relevant sections of "How to Brew" and simply give it crack. Got to get my feet wet at sometime.

I really appreciate you taking the time to walk me through the water equation.

I will come back to you with what I eventiually run with an how close I get to the calculated OG/FG.

Cheers n Beers

Jolls
 

Jolls

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Hi Team

So I ran with 3.75:1 L:G for the strike. My boiling vessel holds 3 litres below the ball valve so I started with 16.5 litres. I covered the mash by 25mm and this used most of the water (still had 2 - 3 litres above the bottom of the ball valve. This used pretty much all of the water - MBH you were on the money. Not sure why the L:G ratio in the software is 1.5:1 - I will ask the question. Perhaps I can edit this. But at least now I know my own equipment setup and the steps.

I heated the strike water to 73 C but forgot to pre heat the mash tun so it was down to 63C so added some boiling waterto bring it back to 67C. If the tun was preheated maybe 73 will work - will try that for the next one. When I put the lid on the esky there was 25mm cover. After the hour the 25mm cover was gone but the water level was only a couple of mm below the grain. I expect I need to maybe have 50mm cover so I end up with 25mm cover give or take after the strike. I drained the mash and then added the sparge water to 25mm above and started the sparging process over 15 or so minutes. I kept going until I had 30 litres for the boil (2.5 litres left in the boiling vessel, 3 litre boil off and leaving 24.5 for the cube, then 21 for the fermenter (with 1.5 litres below the tap) to get me 19 litres into the keg. I ended up pretty close - I was able to fill the cuble to 25 litres and had a little left in the kettle.

The following morning I transferred the cube to the fementation fridge at 17 degrees. I checked the OG when I did the transfer to the fermenter and got 1.042 so 1 point above the planned range. It looked pretty pale but I expect this is from the wheat and no inclusion of the roasted barley (it was only 7 grams). So I guess I got the mash and sparge temps and process close to correct.

Thanks for the advice and guidance. I will take more notice of the How to Brew book and check the outputs of the software against it as the first point of call. I will work out how to edit it if I can so that it reflects the process I develop. However, I don't wat to rely on the software for anything more than checking my own figures and recording brews so that I have a record to work from.

Having done my first AG brew now I think I undersand the process much better and more improtantly the mash and sparging process. I look forward to tasting it in a couple of weeks. I expect it will be a pretty pale and light tasting beer good for the back deck on a hot day!

Edit: I worked out how to edit the water profile in Brewers Friend - so now it should simply work! - but I will cceck the first few until I am happy it has been cracked.

Cheers n Beers
Jolls
 
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