Efficiency: 50%

[Oblomov]

My efficiency for the last 3 brews was around 50%. I originally blamed a too small brewpot (had to throw out some wort), but I bought a bigger one for the last brew and I'm still having the same problem. Since it's so unusually low, there must be something fundamentally wrong. Any thoughts are much appreciated

Basic setup

• I buy my grains pre-cracked from my LHBS and use them within a week.
• My mash tun is a 50 liter rectangular cooler with a braided hose.
• I am not 100% sure I can trust my thermometer (my third).
• I use a regular hydrometer.
• I do batch sparges.

My last brew was an IPA with this grain bill:

• 6.00 kg Pale Malt
• 1.00 kg Caramalt

This was my mash

• Add 18.25 liter of water rest for 60 min at 69C down to 67C
• Add 6.50 liter of water, rest for 10 min at 72C
• This gave me 19 liters at 1.052
• Then I added 16.50 L of water at 75.0
• This gave me 15 liters at 1.026

I boiled it down to about 25 liters with an OG of 1.052, beersmith tells me my efficiency was 53%.

Basically, I think it must be either my thermometer (I have 3 and each indicates a different temperature), the grain or the pre-cracking by my LHBS.

Now before I spend event more $$$ on yet another thermometer, a grain mill and bulk grains from elsewhere. What could be the most obvious cause of my unusually low efficiency?

 

[tangent]

denaturing some enzymes from too hot a strike temp?
crappy milling- too course?
does your beer taste ok?

 

[Ash in Perth]

check your thermometers in boiling water. (distilled is better) the closest to 100 is the best one. I used a thermo that read 5DegC under for a while. still got ok efficiency when mashing at about 70DegC.

Does your home brew shop person crush it in front of you or it is in a bag crushed already? could have been there for a while.

 

[Oblomov]

Wow. Quick. Thanks.

denaturing some enzymes from too hot a strike temp?

Possibly. To get a feel for this, how many degrees too hot would cause an efficiency this low?

crappy milling- too course?

I have nothing to compare this to, but I took a closeup of my mashtun before adding the water. This is the caramalt:

No picture of the pale malt, I'm afraid.

does your beer taste ok?

I think so.

 

[Oblomov]

check your thermometers in boiling water. (distilled is better) the closest to 100 is the best one. I used a thermo that read 5DegC under for a while. still got ok efficiency when mashing at about 70DegC.

I'll try that.

Does your home brew shop person crush it in front of you or it is in a bag crushed already? could have been there for a while.

In a bag , but I pre-order by e-mail, so I'm asking for it I'm assuming having it lying around for a week or so is OK?

 

[vlbaby]

oblomov,
just curious, are you calculating your efficiency based on the final fermenter quantity being the batch size?

My promash tells that you have an efficiency of 59% which is a little better than you calculated.

sorry if this is a silly question.


vl

 

[Darren]

Unless your thermometer is 10 degrees out I would discount that.

6kg of "pale malt" and a kilo of "caramalt" gives me 65% in promash for 25 litres. Not too bad for early brewer efficiency.

What is the base malt you are using?


cheers

Darren

 

[Oblomov]

Hmm. The bags says "cracked pale malt" and "cracked cara malt". Danger sign I presume?

I used beersmith to calculate my efficiency based on 25L at 1.052, but the ingredient I forgot to add above is 350g of cane sugar :mellow: . It says 53%. I might be quoting the wrong numbers but according to beersmith pale malt potential is 1.038, and caramalt is 1.036.

 

[Darren]

sounds about right then. Could be bad malt. Find out what the brand is.

cheers

Darren

 

[vlbaby]

given that additional information, promash gives me 53% also.

Have you given it thought that perhaps your hydrometer is not completely accurate.
its also possible the pre-cracked grain could also be a contributer.
Do you give the mash a good stir after each water addition? If you have, then your procedures look fairly decent to me, so I think you could be looking for a variety of reasons that explain this poor efficiency.

vl.

 

[Tony]

Id say the grain was not cracked enough.

Did it sparge real quick?

I have tried mashing with a slightly courser grist than i usually use and the efficiency drops off real fast

The water runs through without the sugars being released properly.

A good test is to taste the spent grain after sparging. If you can taste sweetness you will have low efficiency.

you shouldnt be able to detect any sweetness.

I would sugest getting your own grain mill or tracking down someone local to you with one and swapping a few beers for a lend.

cheers

 

[tangent]

gotta agree with Tony there
a great piece of brewing equipment there and most people don't use it at all in brewing, just the drinking: your tongue
i worked out that my sparge practices were too inefficient by tasting the waste grain - bugger! i'm throwing away wort!
great for testing hop additions as well.
my efficiency calcs were all over the place and really high. High OGs all the time. Then i started getting stuck sparges with beers containing no wheat. Just too much flour and too fine a grind. Now i back off the grind and add a little more malt.
Low efficiency isn't the end of the world if you don't have stuck sparges and make a beer you like.

 

[Trent]

Oblomov
For 7kg of grain and 350g of sugar (why the sugar?) 1053 seems a little low. I would suggest trying to order some grains from another HBS for your next batch and see how the efficiency goes. I used to get my grains pre cracked from Marks Home Brew in Newcastle. I have no affilliation with him, but am a happy customer. I usually got good efficency from the grains I got from there, his number is 49 696 696, and you can get it sent pretty quickly. Otherwise, look for some of the other more well known brewshops around Sydney, like Norther Districts (I think) or ESB. No affilliation with either or those, and I dont know their numbers! The only other thing I can think of is using a stainless braid in a 50L mash tun may lead to channeling, and alot of undersparged malt. Look up www.howtobrew.com for the research into mash tun manifolds (or appendix D, page 311 if ya have the book). How much do you lose in the bottom of the kettle? I used to lose 3-4L, and I am sure the diff between 25L at 1052 and 29L at 1052 is quite a bit in efficiency. As far as other causes, as a REALLLY long shot, your mash pH may be out, but if you are using tap water, you should be safe (and I am sure there would be flavour indicators aswell). Failing all else, base malt is pretty cheap, and maybe an extra kilo or 2 in the grist could bump up your OG to what you are after. Not the perfect answer, but it will get ya there
All the best
Trent

 

[Ducatiboy stu]

I usually do 3 batch sparges, and give it a good stir in the esky to dissolve the sugars.Try a thicker mash and use sparge water at 80*c. The higher the sparge water temp, the better it will dissolve the sugars. just dont go to high or you will get some nasty tastes

 

[warrenlw63]

Oblomov.

Not too sure if anybody's asked you this yet. Are you by chance using Powells malt?

I found a single temp rest with it was giving me around 52% efficiency. Also your crushed Caramalt looks a bit undercracked as Tony stated. I'd get your HBS to close their mill gap up a little.

Here's a pic of some pale malt I crushed recently. It's Powells Trad. Ale. I employ a 40 degree rest for 20-30 mins, then infuse up to 65 degrees. This puts me around the 75% efficiency region.

If it's not Powells you're using disregard this post.

Warren -

 

[Voosher]

I didn't see the pic of your crush before, but I've got to agree with Warren and Tony (and anyone else who may have mentioned it) about the crush. There are some grains in that pic which look like they haven't even seen a roller.
Tony's point about the speed of your sparge should give an indication. I fly sparge 2.5kg grain in 45mins on average and I consider my crush to be quite fine.
While I'm being so agreeable I concur with Ducatiboy Stu's point re sparge water temp. I got a good jump in efficiency when I lifted it to 80C and have no issues with tannins.

 

[Barry]

Good Day
I agree with the other comments. The main problems will the how well the grain is milled and the type of malt/grain. All other things, unless extreme (eg mashing at 80oC), have far less impact on efficiency IMHO.

 

[Aussie Claret]

My 2c, Barry you said that you are batch sparging , I was told that you should have the sparge water as close to boiling as possible (98c), if you are batch sparging using 2 equal run offs then you run ZERO chance of extracting any tannins, as you only extract tannins when there are no sugars left.

Fly sparging is another matter, as you are flushing away the sugars at the top of the mash down towards the bottom of the tun and risk the possibility of extracting tannins from the grains at the top of the mash.

Having a higher sparge water temp when batch sparging will help to flush out any residual sugars.

Hey I'm only a new AG brewer so what do I know but my advice came from a very respected brewer on this forum.

Cheers and good luck
AC

 

[crozdog]

As a new AG'er myself, I can recommend Gerard @ NDbrewing as a top source of ingredients. He mills to order & delivers for free (in Sydney). Give him a call on 9869 4668 or checkout his web site http://www.ndbrewing.com.au/.

I've used 2 of his recipes with no issue. He always has some useful info he is happy to share as well.

No affiliation etc, just a happy customer.

Beers

Crozdog

 

[Oblomov]

I took your advice and bought grains from ND brewers. This batch, my efficiency was 72%.

Now I'll need to find a nice way to tell my LHBS to get a new grain mill.

Thanks all!