Efficiency Problems. What Am I Doing Wrong?

[warra48]

I've never understood why brewers let their mash sit for 10 minutes after adding water and before draining. Just what is this supposed to do?

I'm hamstrung by a relatively small mash tun of only 25 litres. I use a manifold, designed on the principles outlined in Palmer's How to Brew. Works fine for me. I add a mashout to bring my mashtun up to capacity, stir, immediately vorlauf and run off slowly so as not to set the mash and have it stick. It takes probably about 30 minutes or longer to drain the first runnings. I add my 90C sparge water to fill the mashtun to capacity, stir, and immediately vorlauf and run off slowly. I then need to sparge with a further 5 to 6 litres to collect 31 to 32 litres pre-boil. All up my draining/sparging process takes an hour or longer, but once each step is underway I can leave it be and do other things.

I have no difficulty in achieving 90%+ mash efficiency this way.

I use a MillMaster, set at a gap between 1 and 1.1 mm (depends on where the rollers are when I measure it!). I think it gives me a very good crush at this gap.

I'm convinced a quick run-off is part of the answer the the OP's problem, as are some others in this thread.

 

[jyo]

Lower efficiency also sells more grain, but i doubt thats a contributing factor..... meaning i doubt any home brew shop owner would do this to make a profit! It was never acusing any HBS's of this.
Exactly, Tony. I can hardly imagine rocking up to my suppliers and having them opening their mill gaps up for the sake of 2 dollars. Then offering me a beer, and giving a discount.....kind of cancels things out, really. :blink:

Manticle, your point on hitting consistency is the exact reason why I want to get this right. I have now brewed my 2 favourite beers twice, with both beers coming out decidedly different in flavour due to inconsistencies. It is frustrating.

Cheers, John.

 

[manticle]

I've never understood why brewers let their mash sit for 10 minutes after adding water and before draining. Just what is this supposed to do?

I'm hamstrung by a relatively small mash tun of only 25 litres. I use a manifold, designed on the principles outlined in Palmer's How to Brew. Works fine for me. I add a mashout to bring my mashtun up to capacity, stir, immediately vorlauf and run off slowly so as not to set the mash and have it stick. It takes probably about 30 minutes or longer to drain the first runnings. I add my 90C sparge water to fill the mashtun to capacity, stir, and immediately vorlauf and run off slowly. I then need to sparge with a further 5 to 6 litres to collect 31 to 32 litres pre-boil. All up my draining/sparging process takes an hour or longer, but once each step is underway I can leave it be and do other things.

I have no difficulty in achieving 90%+ mash efficiency this way.

I use a MillMaster, set at a gap between 1 and 1.1 mm (depends on where the rollers are when I measure it!). I think it gives me a very good crush at this gap.

I'm convinced a quick run-off is part of the answer the the OP's problem, as are some others in this thread.

My layman's assumption is that sugar release from grain into solution needs a bit of time to occur. The fact that you are draining very slowly probably has a similar effect.

If I added sparge water and drained straight away in 2 minutes I'm sure a lot of sugar would remain stuck to the grain.

 

[jakub76]

Very interesting thread. I think it should be noted that jyo's last brew was 50% wheat, that will have an impact on efficiency. I've got my rig, esky braided hose batch sparge, up around 73-75% consistently but with hefeweizens I reach 65-69%. I assume it's the lack of husk

 

[Pollux]

I'm watching this closely, I have had constant issues with eff% and I am starting to think too quick of a run off is to blame......

I'll try out a SLOW sparge next time round and see what the result is, should be interesting...

 

[bradsbrew]

I've never understood why brewers let their mash sit for 10 minutes after adding water and before draining. Just what is this supposed to do?

I do it as a settling period because I pour my sparge water in from another pot which also acts as stirring. I have found by letting it sit it will drain clearer.

Cheers

 

[jyo]

Very interesting thread. I think it should be noted that jyo's last brew was 50% wheat, that will have an impact on efficiency. I've got my rig, esky braided hose batch sparge, up around 73-75% consistently but with hefeweizens I reach 65-69%. I assume it's the lack of husk

That is a good point, Jakub, I didn't use rice hulls this time, and the last time I did the same recipe, I used hulls and hit about 68%, which is still low.

But, I'm consistently getting low results.

Cheers.

 

[Spoonta]

John you can buy your grain whole and mill it at my house

 

[jyo]

John you can buy your grain whole and mill it at my house

I know mate. Didn't want to be a bother and all that. I might take you up on that though.
Cheers mate.

 

[Spoonta]

I know mate. Didn't want to be a bother and all that. I might take you up on that though.
Cheers mate.

Mate its not a prob save you some $$ as well buy in bulk

 

[daemon]

The pH of the mash could be having an effect on efficiency as well, have you ever tested it?

I average 70-75% efficiency with a fairly fine crush, my main variable is the sparging stage (batch sparge, esky with a bit of braid). However, the lowest I've ever had was 65% and it was a very rushed brew so I'm happy overall. I use a bit of the 5.2 pH buffer to help adjust my tank water and it helps ensure consistency.

 

[browndog]

Bdog and Stuster are you guys using a pump to recirc during mash? Also if you are giving a good stir between sparging what time are you wiating before drain off. And how is channelling not a problem? And the 30-60 min was related to 66L batch as stated.

Cheers

Brad here is what I do,
At the completion of the mash drain the tun, refill with half the sparge water at 90C, stir it really good then start recirculating (with a pump) straight away till the chunky bits vanish and then into the kettle. No waiting 10 mins, no draining for 30 mins I drain as fast as the mash will allow, then repeat, 82-85% efficiency every time. The burner is fired up as soon as the first runnings are drained and I have a rolling boil 30 mins after mashout. How simple is that?

Disclaimer, my opinion is based on experience only.

cheers

Browndog

 

[Thirsty Boy]

Getting your grain bed up to the right temp, a good stir and 2 equal run-off volumes should really take sparging out of the equation as the cause. Also a bit of a waiting period after you add the sparge water and before the second run-off (as MHB said) it doesn't really matter so much before the first run-off... but you need time for sugars to diffuse out of the grains when you add fresh water. I add my sparge water, stir, wait a few minutes, re-circulate for a few more minutes and run off.

I get the wort out of the tun as fast as I am able - If you have given things a little time to dissolve and stirred the grain bed up well... then you should be looking at a situation where the distribution of the sugars is even throughout the mash and channeling etc cannot be an issue. If you didn't stir well enough and/or you didn't give the sugars time to dissolve out of the solid matter and/or you didn't distribute them fairly evenly with another stir or with a thorough re-circulation step - then you need to be concerned with run-off speed and with channeling.

Note: With a bunch of stirring - you do get a layer of fine yurk settling on top of your grain bed. This can seal up the top of the bed, force wort to channel down the sides of the tun and also make your mash bed compact. None of that matter to your efficiency if you are batch sparging (assuming you did all the things above) - but it can drastically slow down your run-off or stick it completely, and it can wreck your lauter efficiency totally if you are continuous sparging. Poke holes in the layer of gunk, or cut slits in it with a knife - just like the knives in a commercial lauter tun.

Or run off more slowly... achieves the same thing in the end really.

 

[under]

Never really had efficiency problems since I started. 20 BIAB's AG under my belt 75% each time. barley crusher with default setting.

 

[jyo]

I have been meaning to update this for awhile.
My results have improved dramatically since changing a few things in my process.
I brewed the same recipe about a month ago-
2500 galaxy
2500 wheat
100 carahell
Tett to 17 IBU
My early effort at this recipe gave me 25 litres in the fermenter with an original gravity of 1038 and 34 litres in the kettle @ 1031

My more recent effort after changing my process is as follows-
32 litres into kettle @ 1042
23.5 litres in the fermenter @ 1051

The things that I have changed after some very helpful advice from a few blokes on here is as follows-

1. Drained my 1st runnings (without a mash out, or stir) into kettle after mash has finished, apply heat to kettle straight away to set the mash profile
2. Drained slower, about 1.5 lires per minute, instead of flat out
3. Increased the temperature of sparge water to 90'
4. Removed the mash paddle during sparge to avoid channelling
5. Stopped brewing pissed as a parrot, limited my intake to 6 pints..... :icon_cheers:
6. After advice from Screwy, I have actually decreased the amount I stir during mash in. This has reduced the grey, sludgey flour on top of the mash
7. Pre-heating my mash tun for 10-15 minutes. This minimised my temp drops during the mash.
8. Bought my own grain mill, and now crush a bit finer. Don't know what a stuck sparge is, even with a 50/50 barley wheat grist.
Consistency is great.

Cheers to all :icon_chickcheers: