I am using the Blichmann tower of power for mashing. I mentioned this to my LHBS and one of the employees told me it is a bad idea to continuously recirculate your mash throughout the entire mash process. He claimed it will "break down the enzymes" and change beer profile.
Recirculating through entire mash process
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I think he is talking out of his ass and he couldn't really support his argument when presses for clarification. Any one on here have thoughts on continuous recirc? The benefits of temp stability are obvious, but wondering if there really is a downside.
cracked1
Well-Known Member
Ask him what he thinks is happening in a RIMS or HERMS system. I don't think I'd take anything he says very seriously.
orangehero
Well-Known Member
Whipping the mash for 60+ minutes with a centrifugal pump running full blast through a half-open ball valve causes protein shear.
With the typical setups I don't think the effects are significant enough to cause issues regarding diastatic power and body/head retention, although you might see some issues with slower draining or stuck mashes.
Commerical breweries do try to avoid it, stirring or transferring the mash/wort as little as possible, using large tubing and pumps and controlling pump speed via VFD (not throttling the outlet).
https://www.homebrewtalk.com/f11/reasons-not-use-electric-pump-367814/
With the typical setups I don't think the effects are significant enough to cause issues regarding diastatic power and body/head retention, although you might see some issues with slower draining or stuck mashes.
Commerical breweries do try to avoid it, stirring or transferring the mash/wort as little as possible, using large tubing and pumps and controlling pump speed via VFD (not throttling the outlet).
https://www.homebrewtalk.com/f11/reasons-not-use-electric-pump-367814/
Hmm. . . . very interesting. I never thought about it as a shearing issue, but that might make some sense. I am guessing that ajdelange was eluding to the fact that shearing the wort during mash can lead to a shear thickening effect, which would explain a resultant problem lauter/sparge (if the viscosity increases sufficiently, then it will be hard to get wort to run). This makes sense to me with regards to a fluid flow problem, but I am trying to understand if it could have an impact on efficiency, fermentation issues, haze, body, head retention and last but not least, taste.
How would shear stress impact these issues?
How would shear stress impact these issues?
I just made a similar post in another thread, far less eloquently perhaps...
Two thumbs up. Pumps are to be minimized, or ideally avoided completely.
Taste, absolutely. Think about how hot the wort gets within the pump head running at motor speed. If there's any air at all, the pump does a great job of whipping it up even finer and making sure it doesn't just bubble out of the mash. The whole recirc through a line through a pump running fast back to the top of the mash and worst of all trying to strain all this through a false bottom made no sense. I mean don't even get me started on the whole issue of plastic mash tuns, please.
So, you have aerated, overheated wort, and maybe a stuck mash or clogged and stuck pump or both. Why was this a good way to mash, exactly?
processhead
Well-Known Member
I think the practical benefits of constant recirculation offset any theoretical negatives.
I usually operate the recirc. pump at a low flow rate, though. Just enough flow to ensure uniform mash bed temperatures, avoid a compacted grain bed, and clear wort during the run-off. No flavor issues noted after 7 years of this.
I usually operate the recirc. pump at a low flow rate, though. Just enough flow to ensure uniform mash bed temperatures, avoid a compacted grain bed, and clear wort during the run-off. No flavor issues noted after 7 years of this.
where are studies supporting this "anti-pump" movement?
Save the bro-science... it just sounds like propaganda w/o any solid research behind it.
I can only imagine how many medals have been won on a RIMs/HERMs system
Save the bro-science... it just sounds like propaganda w/o any solid research behind it.
I can only imagine how many medals have been won on a RIMs/HERMs system
jammin said:
I agree jammin. I am trying to understand the theory (I.e. science) behind why constant recirc might've negative. I have been using direct fired RIMS for a full year now and happy with results. My overall brewing has improved (proper pitch rates, temp control, proper oxygenation, etc.) so it is hard for me to isolate main reasons for improvement.
I am tempted to try no recirc and see what impact it has on final beer.
If the flow is slow, I don't think there is any problem. If it is fast though then the above can come into play. A good way to denature proteins (besides heat) is to vigorously mix them - especially if there is a little air around.
This is what happens when you whip cream. The proteins denature and get all sticky, and create a massive stable foam. If you've ever made whipped cream though you know it take a bit of mixing to make it. If you whip slow, it won't work.
Or in other words, if you are seeing foam, then you are losing enzymes. No foam, then you are probably OK
I have never seen attenuation issues with my recirculating system - mag drive pump - and I think the beer has been outstanding. Were shear and heat to be an issue then I think I would have noticed - and I suspect IF there were to be an issue then it would be due to mid-sized pump or poor flow due to thick mash. There are no yeast in the mash (at least none that we want to survive the boil) so that is a min-issue IMO.
Some breweries use a circulating fermentation system and produce very clean beer.
I don't know it all so I hope the tone of the above doesn't read like I think I do!
Some breweries use a circulating fermentation system and produce very clean beer.
I don't know it all so I hope the tone of the above doesn't read like I think I do!
please cite the source of your information. I'm sure we would all like to read the study that related the effects of making whip cream to mashing grains.
Take you pick of any protein. Have it in a solution and start to beat it, as long as there is enough protein in the solution, it will form a stable foam. (just how stable depends on the protein). Every biochemist who works with protein knows this and are very careful when mixing protein solutions.
Cream has protein in it, so does wort, both will form nice stable foams if you mix it vigorously enough. Once in this state, the proteins will never regain their enzymatic activity. The exception would be in a living cell where there is machinery to refold some denatured proteins. That does not exist in the mash tun (or in whipped cream). If you create a lot of foam during mashing, you are losing enzyme activity.
A quick search on handling protein solutions (of which wort is) in order to maintain enzymatic activity. 1st two hits
Wort is not some magic solution to which normal protein stability rules do not apply. One property thankfully that some of the brewing enzymes do have that most other enzymes don't have is a very good thermal stability.
Cream has protein in it, so does wort, both will form nice stable foams if you mix it vigorously enough. Once in this state, the proteins will never regain their enzymatic activity. The exception would be in a living cell where there is machinery to refold some denatured proteins. That does not exist in the mash tun (or in whipped cream). If you create a lot of foam during mashing, you are losing enzyme activity.
A quick search on handling protein solutions (of which wort is) in order to maintain enzymatic activity. 1st two hits
Wort is not some magic solution to which normal protein stability rules do not apply. One property thankfully that some of the brewing enzymes do have that most other enzymes don't have is a very good thermal stability.
Your link wont work for me and I cant seem to pull it up by searching it on the web.
In any case - you need to be more concise about how this relates to the OP. Specifically, how does this change the profile of the beer?
Furthermore - you need to have some sort of quantifiable information you can support. Ideally, this information would support some sort of limit relevant to the home brewer in terms gallons per minute, etc..
BTW - nobody "beats their wort into a foam". The argument is about shearing forces produced by running your wort through a pump.
In any case - you need to be more concise about how this relates to the OP. Specifically, how does this change the profile of the beer?
Furthermore - you need to have some sort of quantifiable information you can support. Ideally, this information would support some sort of limit relevant to the home brewer in terms gallons per minute, etc..
BTW - nobody "beats their wort into a foam". The argument is about shearing forces produced by running your wort through a pump.
Off topic a bit, but I am wondering if this is also the same theory on why not to burst carb your kegs by shaking? The theory I've heard is that once the proteins in the beer foam up that they will not do so again, and head retention is forever impacted. I would also think that the beer would be less stable in the long run, impacting longevity.
I've heard the don't shake as once foam is made the proteins will never foam again story. I'm inclined to believe this, but I haven't seen a study. Formation of foam involves unfolding of the proteins. Once unfolded it is difficult to refold. The question is can these unfolded proteins reform a foam once the foam has settled, or is it new protein that make it foam again, which then could get used up eventually.
I had a bottle of wort that I would shake a couple times a day a work. It would always foam up, at least for the 2 weeks or so I did this. The only real difference I noted was maybe the bubbles became a little more coarse - but it still foamed well. Of course this was not fermented and yeast change the proteins during fermentation, both by modifying the one in the wort as well as secreting new ones
If one is denturing proteins in the mash for any reason (wrong pH will do it too) then the efficiency will drop resulting in a lower than expected OG and you will likely end up with a high FG as you will have a lot of dextrins left due to inefficient conversion
I had a bottle of wort that I would shake a couple times a day a work. It would always foam up, at least for the 2 weeks or so I did this. The only real difference I noted was maybe the bubbles became a little more coarse - but it still foamed well. Of course this was not fermented and yeast change the proteins during fermentation, both by modifying the one in the wort as well as secreting new ones
If one is denturing proteins in the mash for any reason (wrong pH will do it too) then the efficiency will drop resulting in a lower than expected OG and you will likely end up with a high FG as you will have a lot of dextrins left due to inefficient conversion
But think about how your pump works... it is pretty similar to a egg beater (except there is no conter-rotating beater to relly mix things up).
I say the theory is there but the emperical results show that pumping is not an issue.
Thinking bout the conversion power of most base malts - you could loss half you enzymes and still have enough to convert your mash.
orangehero
Well-Known Member
For a normal all-malt mash there's likely nothing to worry about, but there may be issues with high-adjunct mashes (lots of wheat or rye) that are low in diastase and high in ß-glucans (that may become more gummy). My impression is commercial breweries are more concerned with the latter as it's important for them to drain and filter the wort as rapidly and efficiently as possible.
dyqik
Well-Known Member
A well designed and properly primed pump doesn't work at all like an egg beater. It's designed to move fluid, without cavitating or forming a foam. An egg beater is designed to produce foam and to drag air into the liquid. There's no air in a properly primed pump to be dragged in, and a pump should not be cavitating. If you had a bad prime, then the egg beater analogy might be relevant.
Agreed as well Jammin.
Bethebrew, where do you get this?
I constantly recirculate. I'm my own worst critic, and seem to have some pretty tasty beers with good head retention.
I listened to a pod cast today about beer clarity. They talked about protiens and "hot side airation". Protiens are robust, and hot side airation (at the HB level) is a myth.
I think you're arm-chair quarter backing a little here.
Dermotstratton, make your own conclusions. I learned a long time ago my LHBS guys are stuck in thier ways, and I just need to learn from experience.
Bethebrew, where do you get this?
I constantly recirculate. I'm my own worst critic, and seem to have some pretty tasty beers with good head retention.
I listened to a pod cast today about beer clarity. They talked about protiens and "hot side airation". Protiens are robust, and hot side airation (at the HB level) is a myth.
I think you're arm-chair quarter backing a little here.
Dermotstratton, make your own conclusions. I learned a long time ago my LHBS guys are stuck in thier ways, and I just need to learn from experience.
Protein shearing is a real phenomenon and CAN be an issue. However, for most homebrewers, it is typically not an issue. Done properly, any shearing losses during recirculating are negligible. It is easily minimized.
We need to be careful in that just because somthing isn't an issue for many of us, that doesn't mean it isn't for others. We do them a disservice to tell them it is not something to ever worry/think about. There is quite a diversity of brew systems out there, and an even greater diversity of homebrewers out there doing all kinds of weird stuff as part of their brew process. There is probably some guy out there using a cheap drill pump to do recirculating (probably through garden hose too) and creating all kinds of bubbles/foaming during the mash. He'll read this thread and think, cool, shearing is BS, I'm good to go, I can ignore all this foam in my mash tun. (Although if he likes the end result, more power to him).
We need to be careful in that just because somthing isn't an issue for many of us, that doesn't mean it isn't for others. We do them a disservice to tell them it is not something to ever worry/think about. There is quite a diversity of brew systems out there, and an even greater diversity of homebrewers out there doing all kinds of weird stuff as part of their brew process. There is probably some guy out there using a cheap drill pump to do recirculating (probably through garden hose too) and creating all kinds of bubbles/foaming during the mash. He'll read this thread and think, cool, shearing is BS, I'm good to go, I can ignore all this foam in my mash tun. (Although if he likes the end result, more power to him).
I guess that's something we need to always consider, that because some issues are not a problem for many of us at the homebrewing level that they don't exist. I would say the same thing is true for other phenomena like HSA.
It exists, but most brewers would say it's not an issue. I would never call it a myth, as it does exist and could happen under the right (or rather, wrong) circumstances coming together.
k_mcarthur
Well-Known Member
I have used an e-herms for almost a year now and love it! I recirculate for the whole mash and have had some issues with foaming a couple of times, but didn't seem to affect final product. I make a Belgian wit almost once a month with almost half wheat and oats without any consequences, I regularly get 85% efficiency. The convenience of a pump or two far out weighs any theoretical negatives discussed here.
I have a TOP controller and recirculate through the mash and on all transfers and whirlpool and transfer to fermenter. I have zero issues with attenuation or head retention versus the old days when I used to use gravity. I have a friend who is a pro brewer who recirculates through the second half of his mash, but whirlpools with a boat oar citing the same concern about issues of whirl pooling with a pump (despite the whirlpool setup on his boiler).
I'm not saying it couldn't happen. But it has never happened to me and I'll test fate by saying I doubt it ever will.
As for stuck mashes, let it settle for about 10 minutes after you dough in. Start your recirculation slowly and then get it flowing enough to avoid scalding (about 1/3 open on the valve for me). I also tend to have a higher liquor to grist ratio due to the height of my false bottom. This has prove useful for avoiding stuck mashes I suppose.
Again, I'm not saying this isn't theoretically a concern. Science surely backs it up. But I'm not changing my process as long as I'm not having trouble. YMMV
I'm not saying it couldn't happen. But it has never happened to me and I'll test fate by saying I doubt it ever will.
As for stuck mashes, let it settle for about 10 minutes after you dough in. Start your recirculation slowly and then get it flowing enough to avoid scalding (about 1/3 open on the valve for me). I also tend to have a higher liquor to grist ratio due to the height of my false bottom. This has prove useful for avoiding stuck mashes I suppose.
Again, I'm not saying this isn't theoretically a concern. Science surely backs it up. But I'm not changing my process as long as I'm not having trouble. YMMV
Some very interesting responses. I appreciate the exchange of information on the forum. It is a great source of information that can be evaluated for accuracy be each member.
A few response comments in no particular order:
1. I rarely listen to the advice from my LHBS. They were great at getting me started, but their arrogance and refusal to embrace new techniques has resulted in a very constrained method of brewing. If I did not decide to try new things, I would be a worse brewer.
2. While I appreciate cited sources for information I do not feel as thought it is a pre-requisite to post an opinion of forums. If I want a "validated" scientific fact, I pursue it on my own system. Scientific journals can even publish incorrect findings, so while it has more creditability than someone conducting science in their garage, it is not necessarily more accurate.
3. The impact of a particular setup has a HUGE impact on findings. Most of us brew "non-standardized" setups, so as mentioned, it is hard to evaluate impact on a setup you have never used.
I was hoping this thread would help me in learning about new theories (which it has) and now I can evaluate them and see how it impacts my brewing. The final thing to remember is that some of us strive for perfection, so even if you deem the impact the be negligible, it is still important for others to know it is there and attempt to avoid it.
I'll try to remember to post back anything new I learn as a try altering the impact of shear introduced by using a pump to constantly recirculate my mash. It would be great if others could share their experience as well.
A few response comments in no particular order:
1. I rarely listen to the advice from my LHBS. They were great at getting me started, but their arrogance and refusal to embrace new techniques has resulted in a very constrained method of brewing. If I did not decide to try new things, I would be a worse brewer.
2. While I appreciate cited sources for information I do not feel as thought it is a pre-requisite to post an opinion of forums. If I want a "validated" scientific fact, I pursue it on my own system. Scientific journals can even publish incorrect findings, so while it has more creditability than someone conducting science in their garage, it is not necessarily more accurate.
3. The impact of a particular setup has a HUGE impact on findings. Most of us brew "non-standardized" setups, so as mentioned, it is hard to evaluate impact on a setup you have never used.
I was hoping this thread would help me in learning about new theories (which it has) and now I can evaluate them and see how it impacts my brewing. The final thing to remember is that some of us strive for perfection, so even if you deem the impact the be negligible, it is still important for others to know it is there and attempt to avoid it.
I'll try to remember to post back anything new I learn as a try altering the impact of shear introduced by using a pump to constantly recirculate my mash. It would be great if others could share their experience as well.
I sized and applied and sold pumps professionally for many years. In the case of recirculation, anything larger than needed will apply more energy to the product than needed. All the talk of protein shear in this thread is not the important issue. Any extra time in the pump head, and excess pumping capacity, results in at least some extra heating and aeration of the product.
If you are a commercial brewer, you probably have no choice, you will be using pumps. The trend is to slow the pump way down to meet the application requirements, not just let the pump run wild or worse have to throttle it back.
As a homebrewer, I use a gravity system. I want the absolute minimum working of anything. Smooth, easy flowing. I use batch mashing, with three runnings typically. There are far easier/cheaper/more effective ways to strain than using a false bottom. Stainless braid hose works fantastic.
Recirculation simply is not needed assuming you can make a three tiered gravity system.
