Recirculate during mash?

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user 40634

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Hi, Quick question from a newbie: During the mash stage do I recirculate the liquid? I’m using a 35L Brewzilla that came with a recirculation pipe.
Thanks
 
Generally yes is the answer just make sure you adjust you overflow pipe to just above the mash grain and the actual flow with the tap so it does not build up and go down the overflow pipe too much
 
Yes - the reason that you do this is so the liquid passes through the grain bed many times

In the grain husks there is an enzyme that helps the starch break down into sugar. This process is known as lautering - more sugar from the same grain bill = Higher mash efficiency
 
I'd suggest watching some brewzilla/robobrew videos on YouTube to get a feel for operation. It's quite simple but there's a few tips and tricks to learn from before you get confused mid-brew. I'm glad I did.
Good luck...
 
I'd suggest watching some brewzilla/robobrew videos on YouTube to get a feel for operation. It's quite simple but there's a few tips and tricks to learn from before you get confused mid-brew. I'm glad I did.
Good luck...
Thanks Sifty
 
I use a 3 vessel set up without a HERMs or RIMs option.

I can’t recirculate during the mash at risk of losing temperature but would there be any benefit (or negatives) in recirculating for a short time after the mash has completed?
 
Generally yes is the answer just make sure you adjust you overflow pipe to just above the mash grain and the actual flow with the tap so it does not build up and go down the overflow pipe too much

Sorry to hijack this thread slightly (although related) but there was a recent David Heath video (part of his 'Brewing Bad' series) which suggested that you should leave the recirculation full bore and just let it flow down the centre pipe if that's what it wants to do. His argument is that this is the very purpose of the overflow pipe and that we've all been getting it wrong by adjusting the flow using the tap on the recirculation pipe. He also argued that this allows more wort to flow through the grain bed overall and so improves efficiency.

I was surprised that this was what you are supposed to do and thought it would just lead to grain escaping the malt pipe and being present during the boil. I tried it on my last brew and - lo and behold - grain ended up in the boil. The top perforated plate stops most grain escaping, but there are always little bits that manage to get out.

Did anyone else see this video and have any thoughts? I'm likely to go back to my old practice of adjusting the flow as a slightly reduced efficiency is the lesser evil compared with grain in the boil in my opinion.
 
Interesting idea. I've never had issues with efficiency with the Brewzilla by turning flow down to prevent overflow. Tend to agree any benefit would be outweighed by pump blocking etc...
 
I don't recall if I've seen that particular video, but I'm sure I've seen him (or another YouTuber) use an upside down tea strainer or small sieve over the top of the overflow pipe to prevent any grain going down and into the wort.

Yes, I think he does, although his point is that these single vessel systems with overflow pipes are designed to overflow during the mash and so the recirculation should be left at full flow. Since none of these systems come with a filter for the overflow pipe, I'm sceptical that's right. I've always assumed the overflow is there as a failsafe, so that, in the event of a stuck or slow draining mash, the area under the malt pipe doesn't run dry causing the elements to scorch.
 
I use a 3 vessel set up without a HERMs or RIMs option.

I can’t recirculate during the mash at risk of losing temperature but would there be any benefit (or negatives) in recirculating for a short time after the mash has completed?
Recirculating after mash is complete would have some similar effect to sparging. Up to a point, any densely concentrated sugars in the grain bed will become more equally mixed into the wort as it is recirculated. This should help with sugar extraction and should be worth doing before sparging.

If you do full volume mash or BIAB it will also help.
 
Yes I have seen that video and think he is wrong. Brewtools who make their own system actually declare the overflow pipe as a failsafe in their systems and to avoid dry heating elements and grain in your wort which would happen if you let it full bore and flow down the pipe this on the Brewtools website.
 
I use a 3V type setup and would certainly encourage recirculating during the mash as in my experience it improves efficiency (in my case from 74% to over 80%).
I go a step further and recirculate via my counterflow heat exchanger whilst circulating temperature controlled water through the jacket, in order to maintain or adjust the mash temp
 
I use grainfather on full bore. If you can get the seals to properly seal and use the additional overflow filter you don't have a problem with grain in boil. Most of the time if you have the level right it stops overflowing after a while anyway, although this varies brew to brew malt batch to malt batch. Using the tap to adjust flow will put back pressure on the pump. Whether this will adversely impact the pump I have no idea.
 
I didn't know there was a separate overflow filter for the Grainfather. I might give it a spin with the Brewzilla
 
I use a brewzilla at the moment and use an upside down Asda strainer with the handles pulled off over the overflow, You have to have a bend or any means of letting the wort travel under it if the strainer becomes blocked with flock. if this happens the wort will overflow the basket!!
The higher the flow I find lets the temp stay at the setting temp as the wort is heated at the bottom, so better recirculation gives better heat stability. (you don't want wort just sat at the top cooling). When I used a thermometer at the hose end it was more consistent with the flow higher. I am usually at mid range of flow when I do it and find it works ok and the strainer is a good addition.
 
I have seen the video and am still undecided I attempted to leave it on full bore for my last brew but bottled it as my grain crush was a little too fine resulting in a partially stuck mash, so I only managed it for 75% of the time. However by allowing a constant flow I did notice that the mash temperature was constant ( something I usually struggle with ) I prevent the grains going down the pipe by using the GF overflow filter I shall persevere and see how I get on in future brews
 
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