Appalling Efficiency!

[Jewels]

Hi. New member here, getting into brewing, very interested and enthusiastic, looking for some guidance on step 1: the mash.

Having bought some reasonable home brew equipment, I have now just completed my third all grain brew day. Learning all the time but seem to be really stuck on something.

I have been very careful to measure water and grain, and hit the right temperatures (72/64 degrees) for the right amount of time, and for the third time in a row, my mash is giving me an efficiency of about 25%!!! I admit I have not allowed for temperature at the time of reading but clearly there is something badly wrong here. The SG on the wort before sparging yesterday was 1.029 after 1 hour 10 minutes at 64 degrees. That was from 13.5 litres of water and 5 kilos of grain. Even I know that's not right!

Not being experienced, it has taken me to this 3rd attempt to conclude that the problem MUST be with the grain. It says it is crushed and it smells fantastic but it simply isn't yielding enough. Do you think I'm am correct in this conclusion? Is there anything else that could produce such terrible results?!

Many thanks in advance,
Jules

 

[honeymonster]

Just popped your numbers into an online calc I found for temp correction.

1.029 @ mash temp corrects to 1.044.

Is that more inline with what you expecting?

Never done AG myself so I'm not sure if that's any help.

 

[Dads_Ale]

A few questions.
What was the gravity of the wort once it was in the fermenter and what was the final volume?
Also what temperature were you taking the initial reading from the mash tun at?
Do you know what the PH of the mash was at the start?

The mash is normally 90 mins so yours is a bit short.

 

[brewpirate]

Any pictures of the crush?
Recipe?
What does your brewing system consist of?
What was your mash thickness?
Batch or fly sparge?

 

[chrisstuarthall]

What method of all grain brewing are you using?

What equipment do you have?

I use an AG BIAB system.

 

[Jewels]

Hi guys. Many thanks for the replies. All interesting stuff. So here goes with some question answering.

@honeymonster. Thanks for this. I knew it would not read accurately when warmer so I have now also looked at a calculator on line. You are right that 1.029 at 64 degrees translates to 1.044. Unfortunately this still only gives me an efficiency of 48%, well below my target. I will use a calculator in future though.

@Dads_Ale. My concern at the moment is before I get near the fermenting vessel. What I actually did was another mash of half the amount of grain again, put it all together and reduce the bejesus out of it. I was wondering whether this may harm the brew but I see from other comments that it should not. So I ended up getting 1.048 in 19 litres at 25 degrees, but had to use a total of 6.5 kg of grain and a lot of boiling to get it! My original mash tun OG was taken at 64 degrees but you can see the correction in my reply to honeymonster above. I have not yet measured the PH as am not sure how to yet - haven't got that far yet! I will however try mashing 90 as a norm though if you think that is required.

@brewpirate. Trying to attach a picture of my mash tun and the grain. Any observations welcome. In terms of the mash thickness, I used 13.5 litres of water heated to 72 degrees with 4kg of grain. My first measurement of OG was the concentrated stuff first out of the mash tun BEFORE I started sparging! It was that first stuff that yielded 38% efficiency and I reckon by the time I had finished messing about if was in the mash for a good 80 minutes anyway.

@chrisstuarthall. I will write my full recipe in a separate post following this one, so this doesn't get too big. Any comments welcome.

Thanks again all. Further opinions as to whether you think my grain is dodgy would be welcome!

Merry Christmas to you all too.
Jules

 

[Jewels]

So my last post only let me put 1 picture, so a picture of my mash tun is attached to this. Here too is the recipe I am using currently, a basic IPA. And I have just noticed I used 4kg of grain not 5, which is what I ised for all my original calculations. Yes I know, but it was a long day. But that still only gives me 48% from my first , most concentrated measurement.

For the first mash, before I did the additional stuff, this is the recipe I used:
3.75kg Golden Promise
0.25kg Crystal Malt
20g Centennial 60 mins
20g Cascade 45 mins
20g Cascade 10 mins
50g Cascade 0 mins

1) Heated 12 litres water to 72 degrees
2) Added in 4 batches to all grain in Mash Tun (pre-warmed with hot water). temp of mash at start 65 degrees. 1st stir @ 15 mins, 64.3 degrees. 2nd stir @ 30 mins, added 1/2 litre hot water, 62.7 degrees. 3rd stir @ 45 mins, added 1 litre hot water, 65.7 degrees
3) 65 mins, Recirculated 2 litres of wort until wort running 'clear'. 64 degrees.
4) 75+ mins Took OG: 1.029 = 1.044. Now 13.5 litres. 13.5 x 44 / 4 = 148.5. 148.5 / 310 = 47.9% efficiency.

See any problems in the above recipe / calculations up to the end of the mash?
Thanks,
Jules

 

[Dads_Ale]

Sorry for all the questions but did you buy all of your crushed malt at the same time. I am no expert but it does not look like a very good crush (having looked at some of my spare stock)
I get all of my crushed malt from the same place but use Maris Otter and have not had any efficiency problems, usually get a gravity of 1050 in 26lts from 5kg pale malt and about 750g speciality grains.

For the mash I add the water first (15lts for 5750g grain), let it settle at 72c and then add the crushed malt. This usually gets me to about 66c. I cover and leave well alone for 90 mins. I have a temp probe built in so can keep an eye on temp but now tend to leave well alone having improved my initial stirring technique (used to get a hot spot around the probe).

For the mash PH the Aldershot place cell PH strips. I usually get a PH of 5.2 having added 1tsp citric acid to the mash liquor.

 

[Jewels]

@Dads_Ale. Many thanks for your reply and don't worry about the questions! Yes, I bought all the malt at the same time. It was meant to be a 25kg bag (why not buy in bulk I thought) but as they dod not have on in stock, then send eight 3kg bags and a 1kg bag. I am VERY glad to hear you say it does not look like a good crush as honestly, I have followed recipes and instructions to the T and this can be the ONLY reason. Do you think I should challenge the supplier?

I presume the gravity of 1050 you mention above is after the boil and as you put the wort into your fermenter?

I have a book, How to Brew by John J Palmer, which is a truly excellent read. He seems to know what he's talking about with over 300 pages of detailed information. He says you should add the water to the grain, not the other way round, but he does not say why (well, he probably does somewhere as he is very thorough but I have not seen it yet), however I have now done it both ways and cannot tell the difference. He does say something about not wanting to shock the enzymes though. All this said, I will follow your 90 minute mash method and see what happens. I also intend to mash with a different (new) pale malt next time to a) see how the crush is different, and b) see whether the results improve. Can you recommend a good, reliable place to buy on-line (I bought from the home brew shop last time which I am guessing is the Aldershot place you refer to)? I will also get some PH strips and read up on it. Would it be a good idea to add citric acid too then? I am guess this gives it a citric taste like Jaipur or Brewdog Punk IPAs?

Thanks again for your help.
Jules

 

[Dads_Ale]

Hi Jules

Regarding the crush I have attached a photo of my last lot of Maris Otter fro the Home Brew Shop in Aldershot

I have always used the HBS for my malts but have also only used Maris Otter pale malt so do not have any experience with Golden Promise. Have not had any issues with the Maris Otter.

I would suggest the best course of action would be to try some Maris Otter and the 90minute mash and see what happens. (I hear the Malt Miller has a good reputation although I have not used them myself).

The citric acid will not impart any flavour but is used (added to the mash hot water, only about 1tsp) to reduce the PH of the mash. You should aim for a mash PH of about 5.3 . You would need to check the PH with a mash as is before seeing if you need to lower the PH as you may not depending on your local water supply.

1050 was the gravity of the wort in the FV.

Good luck

 

[Jewels]

@Dads_Ale

Hi! Thanks for the info here. I did try to post a 'quick reply' before Christmas but checking here today, it obviously didn't work.

Your Maris Otter husks look much more 'open' than my Golden Promise! I have ordered some today and will switch to a 90 minute mash. Will let you know.

I have never tested the PH so have also ordered some test strips so we shall see what results that produces.

I'll let you know how I get on!

Thanks and regards,
Jules