Reasons not to use an electric pump

[Barnesie]

Sorry, this makes me chuckle. Where in the world did you come up with this conclusion? I mean ok sure it's going to destroy hot trub - great that's insoluble protein and we don't want it anyway. But I've never heard of a pump impacting soluble protein.

I heard they also split atoms and that can lead to hot side fission.

 

[ajdelange]

Sorry, this makes me chuckle. Where in the world did you come up with this conclusion? I mean ok sure it's going to destroy hot trub - great that's insoluble protein and we don't want it anyway. But I've never heard of a pump impacting soluble protein.

When you recover your breath go educate yourself as I suggested in an earlier post. Do a search search on 'pump protein shear' on Yahoo or Google. There you will find articles that explain the basic phenomenon of which brewers, but apparently not all brewers, are aware. Now add the word 'beer' at the end to focus on brewing related aspects. At http://morebeer.com/brewingtechniques/library/backissues/issue6.6/depiro.html you will find an article by George dePiro (ironically at the Albany Pump House if he is still there):

"The shear forces produced when pumping wort are also a concern to the RIMS brewer. Proteins (like enzymes) may be denatured more rapidly when subjected to shear forces. When shear forces are excessive, beta-glucans can form a gel that can inhibit filtration of the finished beer."

It's interesting to note that George used to be in the pharmaceutical industry where this is of particular concern WRT enzymes so he would be especially sensitive to this. In brewing the enzymes are of course also involved and it is probably those proteins that are most sensitive.

Then, again as I suggested earlier, you might look in some brewing texts. Kunze, for example, has several paragraphs on this in Section 3.2.4.1. If you do take the trouble to read this you will see that shear also stretches ß-glucans promoting gel formation so this would be another disadvantage to using pumps (and as you saw above dePiro mentions that too).

So these are some of the places in the world from which I drew this conclusion. The fact that you have never heard of a phenomenon WRT brewing does not mean that it is not relevant to brewing. Brewing is such a complex process that one takes a big risk when expressing doubt about an unfamiliar proposition because brewing always has a surprise in store for him. That's one of the neat things about it.

Note that it is not only pumps that produce sheer. Anyplace where a fluid is exposed to a velocity gradient there will be shear. Pumps are an obvious place but remember that velocity is a vector. A fluid running through a pipe at constant flow rate (gallons per minute) is subject to shear at every bend in the pipe. Mash being stirred is subject to shear forces.

Some types of pumps subject the fluid to more shear than others. The piece at www.psgdover.com/assets/case-study_Mouvex_Surly_Sept12.pdf is a 'newsletter' article by a pump manufacturer bragging about its low shear pump and the selection of that pump by Surly brewing.

 

[jcaudill]

Ok - so I understand your point now great. And I will go study my Kunze book - yes - I do have it. But I just got back from VLB and apparently pump shear is not a big concern because not once
did it ever get brought up. I guess my point is - it's not a great reason to not use a pump.

 

[Barnesie]

"The shear forces produced when pumping wort are also a concern to the RIMS brewer. Proteins (like enzymes) may be denatured more rapidly when subjected to shear forces. When shear forces are excessive, beta-glucans can form a gel that can inhibit filtration of the finished beer."

--SNIP--

So these are some of the places in the world from which I drew this conclusion. The fact that you have never heard of a phenomenon WRT brewing does not mean that it is not relevant to brewing. Brewing is such a complex process that one takes a big risk when expressing doubt about an unfamiliar proposition because brewing always has a surprise in store for him. That's one of the neat things about it.

Note that it is not only pumps that produce sheer. Anyplace where a fluid is exposed to a velocity gradient there will be shear. Pumps are an obvious place but remember that velocity is a vector. A fluid running through a pipe at constant flow rate (gallons per minute) is subject to shear at every bend in the pipe. Mash being stirred is subject to shear forces.

So my problem with this being added the conversation about pumps is that it isn't factually specific data that may be actually relevant to the homebrewer. I'm not suggesting that it can't be true, just that without homebrew specific data, it's just theoretical effluvia that may just cloud the conversation.

"Pumps may be denatured more rapidly" and "When shear forces are excessive" doesn't tell the homebrewer anything.

When exactly are shear forces excessive for the homebrewer? Should we never stir so as to eliminate shear forces from our mash paddles? Should we design our systems so that there is a straight sloping pipe from one vessel to the other and eliminate anywhere there could be a bend? What is the data that shows actual cause-and-effect results of shearing on a homebrew scale?

I'm not questioning that this is a fact of science, I'm questioning that it is something the home brewer would ever really need to worry about. Much like all the hubbub over autolysis, some things that are applicable in a large commercial manufacturing operation shouldn't be a real concern for the homebrewer.

I'm not saying you're wrong, I'm saying that I'd love to learn more of how this is applicable on the homebrew scale.

 

[jcaudill]

So my problem with this being added the conversation about pumps is that it isn't factually specific data that may be actually relevant to the homebrewer. I'm not suggesting that it can't be true, just that without homebrew specific data, it's just theoretical effluvia that may just cloud the conversation.

"Pumps may be denatured more rapidly" and "When shear forces are excessive" doesn't tell the homebrewer anything.

When exactly are shear forces excessive for the homebrewer? Should we never stir so as to eliminate shear forces from our mash paddles? Should we design our systems so that there is a straight sloping pipe from one vessel to the other and eliminate anywhere there could be a bend? What is the data that shows actual cause-and-effect results of shearing on a homebrew scale?

I'm not questioning that this is a fact of science, I'm questioning that it is something the home brewer would ever really need to worry about. Much like all the hubbub over autolysis, some things that are applicable in a large commercial manufacturing operation shouldn't be a real concern for the homebrewer.

I'm not saying you're wrong, I'm saying that I'd love to learn more of how this is applicable on the homebrew scale.

Ok I went back and reviewed the section of the Kunze book. What it says (paraphrasing because believe me - Kunze is no easy read) is shear forces produced at higher temperatures by:

- Too fast-moving agitators
- High flow velocities or repeated changes of direction in the external boiler
- Vigorous swirling in the whirlpool
- Too narrow or varying pipework cross sections
- Centrifugal forces (as produced by pumps)

Can lead to an increase in viscosity of the wort which in turn can lead to problems with filtration.

A couple takeaway's from this as applicable to the homebrewer:

1) If you use an agitator (most of us don't), you don't want to create a vigorous whirl. You want to stir with something that has a large surface area (enough to mix the mash), but slowly.
2) You want to control flow during whirlpool to limit shear force.
3) You need to think about your plumbing and making sure you are tapering if necessary and or use a consistent size throughout your plumbing. And use a large enough hose as well.

What Kunze does say is basically, use a high quality malt because in the brewhouse - we can only limit and not eliminate shear forces (practically speaking).

As all this relates back to the OP: I think there are bigger concerns than this. That's my take.

Speaking of the whole plumbing thing: that is a hugely important point AND one that does impact priming on the March Pumps. Use the biggest diameter you can practically use. Many use 1/2" - I think that is part of the problem. I use personally use 5/8" ID and have less of an issue. The last thing you want is restriction in your flow.

 

[ajdelange]

I'm not saying you're wrong, I'm saying that I'd love to learn more of how this is applicable on the homebrew scale.

These are things that commercial brewers worry about more than home brewers but home brewers should be cognizant of them. My goal in home brewing is to make beers better than the ones I can buy. In order to do that I try to arrange things so that I don't experience the negative effects of autolysis (and I tasted plenty of home brew that suffers from it) or shear. Now I do use pumps - there really isn't much alternative but I try to use them as little as possible (which isn't nearly as little as I'd like).

As the DePiro article says, this is of particular concern to RIMS brewers because the wort is in constant motion and thus subject to lots more shear than in a conventional stirred mash. This would tend to cause me not to chose the RIMS approach.

 

[jcaudill]

I'll remind you that the main effect of shear according to Kunze is problems with filtration and that's it. Many of us don't filter so it doesn't even matter. So I wouldn't go abandoning RIMS so quickly.

FWIW - I'm a RIMS brewer and my beers clear up remarkably well.

Filtering is the devil anyway!

 

[ajdelange]

I think he's probably referring to lauter/sparge filtration. That's where ß-glucans are a PITA. Don't know about whether they carry through all the way to the finished beer but I don't think they do. I think they get trapped in the grain bed during sparge. I don't filter either but I do get a lot of stuck mashes (and I do recirculate with a pump).

But that's a separate problem. The protein degradation issue is equally real. Much of the literature seems to focus on enzymes but I'm wondering if the effects on body proteins are appreciable.

 

[Barnesie]

So to summarize this great back and forth debate about the finer points of a textbook:

If you use a pump your beer might be some arbitrary unknown degree harder to filter if you decide to filter it. If you use a RIMS, your wort will appear to be more filtered entering the kettle, however it will also be some arbitrary unknown degree harder to filter if you decide to filter it.

 

[ajdelange]

A better summary would be:

Proteins, in particular enzymes, yeast, and ß - glucans can be effected by shear. This can result in difficult lauter/sparge (and possibly further problems if the finished beer is filtered), poorer enzyme performance and reduced head formation potential. Brewers should, where possible, take steps to reduce shear in handling wort. Larger rather than smaller tubing/piping should be selected and sharp bends eliminated where possible. Stirring should be as gentle as possible and low shear pumps should be selected if possible.

 

[jcaudill]

I think that's well said. But above all: this is no reason not to not use a pump. There is no better method of getting liquid from point A to point B in a reasonable time.

 

[yorkbrew]

Ha what a way to hijack a thread! I'm glad it was though, a probrewer once told me that my plan for a HERMS system was a bad idea because of protein shearing. It's something that has been at the back of my mind for a while now.

I'm wondering if these proteins can still be cleared using traditional fining techniques.

 

[jcaudill]

Just to bring this back to earth - I think we're talking awfully nitpicky right now. I highly doubt most commercial brewers are sitting around a roundtable worrying about shear forces and I've seen plenty of quality products. As for a homebrewer - do what you can do and HAHB.

 

[user 19629]

I batch sparge 5 gallon batches.
I put my mash tun on a table.
I heat my mash water in a pot.
I dump the pot of water in the mash tun.
I heat sparge water in a pot.
I drain mash.
I dump the sparge water into the mash tun.
Depending on the volume I might use a pitcher to transfer the first few gallons of water.
So my reason not to use a pump is that I don't need one.

 

[jgaepi]

Dzlater, I came to that conclusion about 34 responses ago.

 

[sonex]

I batch sparge 5 gallon batches.
I put my mash tun on a table.
I heat my mash water in a pot.
I dump the pot of water in the mash tun.
I heat sparge water in a pot.
I drain mash.
I dump the sparge water into the mash tun.
Depending on the volume I might use a pitcher to transfer the first few gallons of water.
So my reason not to use a pump is that I don't need one.

+1 that was my point too. If you don't want to use a pump, gravity can do all your transfering, you just need to set up your system to let gravity be your pump.

 

[user 246304]

These are things that commercial brewers worry about more than home brewers but home brewers should be cognizant of them. My goal in home brewing is to make beers better than the ones I can buy. In order to do that I try to arrange things so that I don't experience the negative effects of autolysis (and I tasted plenty of home brew that suffers from it) or shear. Now I do use pumps - there really isn't much alternative but I try to use them as little as possible (which isn't nearly as little as I'd like).

As the DePiro article says, this is of particular concern to RIMS brewers because the wort is in constant motion and thus subject to lots more shear than in a conventional stirred mash. This would tend to cause me not to chose the RIMS approach.

OK, I know this is an old conversation, but I'm going through these considerations, so I was hoping to get a bit of fresh thinking on this.

First I'd like to say, I feel as AJ expresses here. We all do, I know - but for me, if there's the tiniest detail possible to improve, on the homebrewing level, I want to do it. Mostly that revolves around treating materials at every process juncture as gently as possible.

Two, on my previous system, I had no pumps. I manually vorlaufed by collecting in a huge ladle, laid it back over the grain bed. I manually transferred via the same ladle, to the BK.

I manually whirlpooled by gathering speed with my mash paddle. Once at a "good clip," (no, no way of knowing speed), I believe the total time from knockout to pulling the paddle was less than 5 minutes. Typically, I'd allow the whirlpool to settle 20-30 minutes. I might have steeped some hops prior to whirlpooling, but not always.

3. I used a 50' DIY copper IC. I don't recall how long it took, but it was acceptable. Obvious issues with coolant water and getting the final degrees to fermentation temp were always difficult. I am considering a closed loop now, whatever system I decide upon.

4. Finally, I obtained a tight cone and always got really clear wort into the fermentor; a point as rigorously important to me as a crystalline vorlauf.

So:

-concerned about hot break shear with a Chugger-driven WC. So, the need for a WP port is itself being questioned in my mind.
-somewhat concerned about cold-break taking place in a CFC or PC, and passing on to the fermentor. This is avoided with the IC.

-I will be able to jump up some in brewlength with this 20 gallon system. I don't know if an IC can cut it, though I know many here have no problems, and this Mr. Malty article on chilling discusses exactly that. If it works, and can get 15 gallons down to 62, I'm in. Cheaper, easier to clean, allays some concerns over cold break in the chiller, gentle on the bitter wort.

Appreciate your thoughts, AJ and all.