Recirculation mash and brew efficiency

[umfana]

I use a biab ace boiler set up and yesterday I rigged up a little solar pump with a PWM modulator (the kind used by people making stir plates) and a PID box I made years ago for sous vide cooking. It's very heath robinson, but it worked for me.

The good things...
1. Temperature control was dead simple, both during the mash and getting up to strike temp. Just set and go.
2. After 30 minutes of mashing the wort was crystal clear. The clearest I've ever seen it.

The bad things...
A) there's more to clean
B) it's less fail safe. A pipe coming adrift mid circulation would be a disaster. So I watched it constantly. Not set and forget.
C) When I removed the bag with the grains in I lost some of the clarity in the wort. Although I recirculated again for 15 minutes through the bag of grain suspended above the boiler and that seemed to clear it up again.

Now something was fuctup in this brew that I can only deduce is a MASSIVE increase in efficiency.

The recipe was for a light refreshing ale (EKG and fuggles). Aiming for an OG of 1039. My efficiency has always been a bit crap at 65%. But consistently crap so I just adjust my recipes to account for this. But this brew hasn't done what I expected.
I screwed up water measurements. At the start of the boil I thought I was 5 litres short. I wasn't, I'd just measured the headspace in the boiler wrong. But I only realised this after lobbing in 4 litres of extra water. Going from 21l expected preboil volume to 25l. Maybe OK for an ale that is not so light in design originally but I don't want dishwater.

So I measured the pre boil gravity after cooling a sample to see if I should be really worried and add some DME. 1041. 20% more wort than recipe AND two gravity points stronger than recipe before I'd even boiled. Wtf?

I no chill, so I have no idea what the pre ferment gravity is yet. But can the recirculation really have improved my efficiency that much?

Umfana

Ps...
Damit - I've just realised in writing this I didn't adjust my hops to the bigger volume.
Pps... And I also forgot my kettle finings.

 

[Bigcol49]

Hi!
Interesting! I'm building a recirculating mash system based on the ACE boiler. Other members with the same setup have commented on a lower efficiency when using the bag compared to using a false bottom and no bag.
Could your higher efficiency be down to better temperature control during the mash?
Have you considered a traditional mash using the bag purely as a filter? This would involve mashing with less liquor, running off the wort into a FV and then doing a recirculating sparge on the grain (still in the bag) to get full boil volume. This would mean you don't have to lift the grain bag until all your wort has run off and you won't lose the wort clarity.

 

[BeerCat]

Tie the return hose on or it might end up spraying down the wall. I use an elastic band as well. Great setup.

 

[MyQul]

Grainfather user (which I understand is a re-circulating system) report excellent efficiency.
I dont know a lot about re-circulating but isn't it in effect sparging with your own wort. So it's going to wash a lot of sugars off the grain as the wort repeatedly passer through it

 

[umfana]

1044 in the fermenter. Significant increase in efficiency. I'll have to do some more with this set up to work out the numbers.


Sent from my ONEPLUS A3003 using Tapatalk

 

[BeerCat]

You don't need the bag or the bazooka filter, just the bottom plate. For sparging i heat up water in another pot. Pour it all on slowly then recirculate for 10mins to get clear wort.

@Mycul Yes its like a continuous sparge with the grain bed acting as the filter. Best upgrade i have made so far.

 

[Smileyr8]

I have a recirculating system and use a Burco Sygnet boiler I hit 88-92% effiency regulary, I tend to scale back the Pale malt in my recipes.

 

[Simonh82]

I have a recirculating system and use a Burco Sygnet boiler I hit 88-92% effiency regulary, I tend to scale back the Pale malt in my recipes.

What is your set up for recirculation? I have a 30L burco and usually manage 80-82% efficiency. Last night I got to 89% but that was with a sub-4Kg grain bill and it was easy to squeeze every drop of wort out after my double dunk sparge.

I've thought about recirculation, more for the fun of the project than a an enormous need.

Does everyone use some sort of PID or do some people just recirculate and adjust the temperature manually?

 

[MyQul]

What is your set up for recirculation? I have a 30L burco and usually manage 80-82% efficiency. Last night I got to 89% but that was with a sub-4Kg grain bill and it was easy to squeeze every drop of wort out after my double dunk sparge.

I've thought about recirculation, more for the fun of the project than a an enormous need.

Does everyone use some sort of PID or do some people just recirculate and adjust the temperature manually?

Be careful doing more than one dunk sparge as you can start to extract tannins as the grain acts less of a buffer for the PH as you wash more sugars of the grain. I found this to my cost and now only do one dunk sparge with maxi-biab now

 

[Simonh82]

Be careful doing more than one dunk sparge as you can start to extract tannins as the grain acts less of a buffer for the PH as you wash more sugars of the grain. I found this to my cost and now only do one dunk sparge with maxi-biab now

Thanks, that is definitely a sensible suggestion but in my case I acidify my sparge water to 5.5 pH with phosphoric acid, so it should be OK for a double dunk sparge.

 

[MyQul]

Thanks, that is definitely a sensible suggestion but in my case I acidify my sparge water to 5.5 pH with phosphoric acid, so it should be OK for a double dunk sparge.

Ok Cool. :thumb:

I started to get a very slight puckering of the lips (thats the best way I can describe it) on some of my beer so started just doing one dunk sparge and that sorted the problem

 

[Smileyr8]

What is your set up for recirculation? I have a 30L burco and usually manage 80-82% efficiency. Last night I got to 89% but that was with a sub-4Kg grain bill and it was easy to squeeze every drop of wort out after my double dunk sparge.

I've thought about recirculation, more for the fun of the project than a an enormous need.

Does everyone use some sort of PID or do some people just recirculate and adjust the temperature manually?

I use a PID and a Solar Pump, its not perfect but its not bad take a look at this thread pages 9 & 10 have some pictures.

 

[Manxnorton]

Grainfather user (which I understand is a re-circulating system) report excellent efficiency.
I dont know a lot about re-circulating but isn't it in effect sparging with your own wort. So it's going to wash a lot of sugars off the grain as the wort repeatedly passer through it

I second that
It's interesting read, like BigCol says.
If I didn't get the GF I'd be in the same boat...

 

[MyQul]

You don't need the bag or the bazooka filter, just the bottom plate. For sparging i heat up water in another pot. Pour it all on slowly then recirculate for 10mins to get clear wort.

@Mycul Yes its like a continuous sparge with the grain bed acting as the filter. Best upgrade i have made so far.

This gives me an idea. Normally, for my maxi-biab at the end of the mash I just lift the bag out and put it in a colinder on top of a bucket to drain, before doing my dunk sparge. What I might try on my next maxi-biab is, before doing the dunk sparge, as the grain bag is sitting in the colinder. Open it and pour the sweet wort from my pot through the grain. Perhaps doing this two or three times. It wont be as effective as a 30 min continuous recirculation but it may give me a bump in efficiency.

I saw something similar being done at UBrew when I used to buy my grains from there. After the mash they would open the tap on the pot. Collect about 5L of wort and pour it back into the pot. They woud do this repeatedly till the wort was clear

 

[Bigcol49]

Hi!

. . . pour the sweet wort from my pot through the grain. Perhaps doing this two or three times. It wont be as effective as a 30 min continuous recirculation but it may give me a bump in efficiency.

If you are going to do this it would establish a good grain filter bed. What if you sparged through this rather than dunking?

I saw something similar being done at UBrew when I used to buy my grains from there. After the mash they would open the tap on the pot. Collect about 5L of wort and pour it back into the pot. They woud do this repeatedly till the wort was clear

I believe this is called vorlauf.

 

[MyQul]

Hi!

If you are going to do this it would establish a good grain filter bed. What if you sparged through this rather than dunking?

.

That sounds like a good idea. With maxi-biab you really do need to squeeze the bag though, as your making a concentrated wort any wort left in the bag is magnified as you dilute it later (if you see what I mean), So the wort wouldnt end up as clear as it would be without squeezing. But this may be off-set by a increase in effeciency so you may not need to sqeeze the bag after all

 

[BeerCat]

This gives me an idea. Normally, for my maxi-biab at the end of the mash I just lift the bag out and put it in a colinder on top of a bucket to drain, before doing my dunk sparge. What I might try on my next maxi-biab is, before doing the dunk sparge, as the grain bag is sitting in the colinder. Open it and pour the sweet wort from my pot through the grain. Perhaps doing this two or three times. It wont be as effective as a 30 min continuous recirculation but it may give me a bump in efficiency.

I saw something similar being done at UBrew when I used to buy my grains from there. After the mash they would open the tap on the pot. Collect about 5L of wort and pour it back into the pot. They woud do this repeatedly till the wort was clear

Since my pump broke i have been manually recirculating and it takes a lot of water to get it clear. Not managed it yet, it improves a bit though. I think your better off putting the bag on a large sieve(or 16" fan cover) and rinsing slowly. Only take about 10 mins. The beauty of this is clearer wort and you can do it in 2 buckets. Save the last for a starter or throw away if you don't need it. I found dunk sparging to be a lot more messy than doing this. I can see you ending up with a pump before long mate.

 

[MyQul]

. I found dunk sparging to be a lot more messy than doing this. I can see you ending up with a pump before long mate.

Your right dunk sparging is messy. That's why I've gone to no sparge for small 7L brews. Dunno about a pump though, I quite like low tech brewing. Less to go wrong that way but I like the idea of the vorlauf. So I might one day add a tap to my new 12L pot

 

[Smileyr8]

so you may not need to sqeeze the bag after all

Always worth giving the bag a squeeze (I use 2 clean chopping boards), I mash at approx 25-27 litres with the aim of 22 in the FV.