Mash in-efficiency

[davebullivant]

Hi all,

Just finished my fourth brew after a break of about 18 months. I am using a whole new set up of kit and am creating very tasty beer, but my efficiency is really bad and getting worse.
I started with 54%, which I thought was ok-ish for a first attempt back at brewing, but since then it has got steadily worse, and yesterday I only hit 30%! Now, I don't really care that much about hitting the right number, but I'm getting to the stage of using 3x as many grains to get to the desired ABV.

So, some details. I am using a coolbox, with a copper manifold (designed using John Palmers How To Brew information on pipe layout). I live in London (super hard water, but put some Murphys AMS http://www.murphyhomebrew.com/tech-sheets/tech_ams.pdf to combat that yesterday, to no avail). Yesterday went as follows.

Grain bill of 13KG, strike water at 78C, dough in slowly.
Hit 68C exactly and lost 1deg over the hour.
Recirculated the first few liters, and then started a very slow fly sparge (I use a plastic plate to pour the sparge water on to the grains to avoid disturbing the bed).

I stirred the mash during the hours rest maybe 3 times, and also stirred it in desperation towards the end of the sparge as i realised the gravity was so low.

After all of that I ended with a preboil gravity of 1.059 (temp corrected).

Here is my grain bill:
UK Marris Otter 6.000 kg 48.8 % 4.1 In Mash/Steeped
German Munich Malt 2.000 kg 16.3 % 2.9 In Mash/Steeped
UK Pale Ale Malt 2.000 kg 16.3 % 1.6 In Mash/Steeped
UK Medium Crystal 1.300 kg 10.6 % 20.5 In Mash/Steeped
UK Torrified Wheat 1.000 kg 8.1 % 0.5 In Mash/Steeped

Really not sure what I am doing wrong. I thought by fly sparging, adding the AMS, and keeping the temp over the hour I would stand a pretty good change of at least hitting 60%, but 30% is so rubbish!!!!

Any tips would be greatly appreciated. As I said, am happy with the beer, but just feel like I am wasting money on grain at the mo.

Thanks in advance.

Dave

[barney]

Have you got your scales set to pounds not kilograms.

[davebullivant]

Ha, no. I wish it was that easy.

[davebullivant]

I wonder whether it's because I am trying to brew a pale ale (ish). I knew that would be harder to do but I didn't think it would make that much of a difference. Maybe I should try a stout and see if there is a big difference. Does anyone else in London have this problem?

[Horatio]

What was your pre boil volume? Just wondered how you are working out your efficiency in case calculations have gone adrift? Seems that you are doing everything you can so maybe if you give us all the figures someone may be able to figure it out? Good luck.

[davebullivant]

I am using Beer Alechemy for my calculations, and am diluting the beer at pitching stage to increase the volume of beer as my boiler is only 20l. Need to adjust for how much the hops drink as i only had 24l at the end this time.Hope the following helps:

Recipe Overview
Target Wort Volume Before Boil: 20.00 l Actual Wort Volume Before Boil: 20.00 l
Target Wort Volume After Boil: 18.00 l Actual Wort Volume After Boil: 18.00 l
Target Volume Transferred: 17.00 l Actual Volume Transferred: 13.00 l
Target Volume At Pitching: 30.00 l Actual Volume At Pitching: 24.00 l
Target Volume Of Finished Beer: 30.00 l Actual Volume Of Finished Beer: 24.00 l
Target Pre-Boil Gravity: 1.115 SG Actual Pre-Boil Gravity: 1.059 SG
Target OG: 1.072 SG Actual OG: 1.058 SG
Target FG: 1.017 SG Actual FG: 1.010 SG
Target Apparent Attenuation:: 75.0 % Actual Apparent Attenuation: 75 %
Target ABV: 7.4 % Actual ABV: 6.0 %
Target ABW: 5.8 % Actual ABW: 4.7 %
Target IBU (using Tinseth): 39.7 IBU Actual IBU: 62.8 IBU
Target Color (using Morey): 30.0 EBC Actual Color: 29.1 EBC
Target Mash Efficiency: 60.0 % Actual Mash Efficiency: 30.8 %
Target Fermentation Temp: 18 degC Actual Fermentation Temp: 18 degC

[Eric]

Hi all,

.......................

After all of that I ended with a preboil gravity of 1.059 (temp corrected).


Any tips would be greatly appreciated. As I said, am happy with the beer, but just feel like I am wasting money on grain at the mo.

Thanks in advance.

Dave

Hi Dave, you will struggle to get initial runnings from a standard mash much greater than 1080. I might have read your account wrongly, but I think you are expecting your preboil gravity to approach double that, which you won't get.
Having said that, those results suggest too low an efficiency. Might I suggest you forget water treatment until you get reasonable extraction and get your thermometer checked, reading low could result in the enzymes being too soon denatured. Then try a normal sized or even mini mash at 65/66C left undisturbed for 90 minutes. Keep it warm but ignor any temperature loss for this occasion. If your first runnings before and after some recirculation are in the region of 1080 it is probable any problem with efficiency will be due to your sparging method.

[Dave S]

Given the information I'd go with sparge inefficiency too. Try one brew using the batch sparge method to see if things improve. I always batch sparge now, as apart from MT volume constraints I can't see any down sides to it.

[Capped]

Given the information I'd go with sparge inefficiency too. Try one brew using the batch sparge method to see if things improve. I always batch sparge now, as apart from MT volume constraints I can't see any down sides to it.

Gotta be worth a go. I never trouble myself with working out efficiencies, but got way higher OG's for a given weight of grist when I switched from fly to batch. Must've saved me tons of grain since then!

[davebullivant]

Thanks guys, will give that a go. The first brew that I did (54%) was with batch sparging, and I switched to Fly as I had read that improved efficiency, but will go back to batch for the next one.

I know what you mean Capped, about not troubling myself, but it's so low that I started to think I must be doing something really wrong.

Eric, I have just bought a new digital thermometer after the first brew as I thought that would be the case, but all 3 of my thermometers read the same so I don't think it is that. It's interesting that I was going for too high an OG. As I was aiming to dilute, i think that is where the wacky target OG has come from.

Thanks all, any other tips would be greatly appreciated.

Dave

[wilsoa11111]

think u need to add in a mash out step- either via decoction (pos most efficent) or infusion (adding boiling water) when i had a consistent setup it made a 7% difference to my efficeny vs no mash out
also get a bigger boiler- or use the pans on the hob as only boiling 20l is asking for aggro, just keep collecting it and adding to the boiler as long as the last addition gets 45mins boiling its all good

also if want that high an abv add sugar, goldensyrup, honey, DIY candi sugar -even extract whatever, its cheaper in the long run

[Dunk]

What tells you to stop sparging? If it's volume into the kettle, and your kettle is small then there are possibly lots of sugars left un-sparged in the mash. A batch sparge would probably help in this case.

To get maximum efficiency you should sparge until the gravity of the wort coming out of the mash tun reaches some thing like 1.006. You would, most likely end up with more volume than you can fit in your kettle in this case.

So, to Improve efficiency you could either tailor your batch size to match your boil kettle capacity, or maybe conduct two boils, combining the results. Or even go full out partygeil and make a big beer and a small one from the same mash...

[davebullivant]

That's a good tip, haven't ever really measured the gravity of the wort coming out, have just done it until I have the right volume.

Will give that a go next time. I have some mystery hops left in my freezer, so I might do a simple single grain mini brew (that I'm not too fussed about) to see if I can get a better efficiency.

Will batch sparge and aim to collect just enough wort and keep testing as you suggested. I was previously always worried about tannins if i left it too lon, but maybe I am being over cautious.

Thanks all.

Dave