Homebrewers Association | AHA Forum

General Category => All Grain Brewing => Topic started by: beer_crafter on January 06, 2010, 02:09:34 PM

Title: First stuck mash: batch sparge
Post by: beer_crafter on January 06, 2010, 02:09:34 PM
I've done dozens of partial mash and all grain brews using Denny's cheap'n'easy mash tun design, and it's always worked well for me.

This past week I brewed a Munich Dunkel with 94% Weyermann Munich I malt, 3% Carafa Special, and 3% CaraMunich.  I belive my crush was finer than I normally crush, since there was a lot of flour.  I did something different with this batch by adding water slowly to the grain in the tun, rather than vice-versa.  Ultimately, I mashed at 152.  When I went to vorlauf, as soon as the runoff cleared, it slowed to a trickle.  I tried to stir up the bed, and the same thing happened.  I attemped to move some of the mash to a different (smaller) tun with the same design, and it got stuck there too.

I ended up changing out the hose that passes through the wall of the cooler to one that had a large ID with the same OD... unfortunately, this is a regular, non hi-temp tube, so I prefer to use the original tube I had been using.  Nevertheless, it, along with a lot of patience, helped me to get through the brew day.

I noticed that there was a rather thick (.5 - 1.25") layer of trub/mud/protiens that sat atop the grains once my sparge was complete.  I have seen a thin layer of this substance before, but never has it been so thick.  I assume it was this substance that was causing the stuck sparge. 

It is likely that this was caused by my crush?   Or is it possible that at some point I unintentionally throughout this pricess did some sort of temperature rest that caused a thick, muddy like protien to form in the mash? 

Next batch, I will be using a coarser crush, but I thought I would ask the group here for opinions as well. 

Title: Re: First stuck mash: batch sparge
Post by: Hokerer on January 06, 2010, 02:23:44 PM
I'd probably look more toward the other process that you said you changed.  That is, adding the water to the grain instead of the grain to the water.  Maybe that created some sort of nasty doughball mess that gummed up your braid.

edit:  hmm, on second glance, you say you transferred some of the mash to another cooler and it still stuck so, maybe never mind.
Title: Re: First stuck mash: batch sparge
Post by: hamiltont on January 06, 2010, 02:29:56 PM
Look into conditioning your grain.  Basically misting the grain with water & let it sit for ~15 minutes before milling it.  It made a huge difference for me. The husks (your filter) are whole and the endosperm is fully exposed.  I also tightened up the mill from .039 to .035.
Title: Re: First stuck mash: batch sparge
Post by: bspisak on January 06, 2010, 03:26:43 PM

One thing I don't like about the braided toilet supply lines it that they use a really fine mesh. The stainless screens (like the bazooka) are a lot courser as are most false bottoms. Perhaps this contributes to getting stuck (I've had one out of my last 6 get stuck, but I just dumped all my batch water in after draining the first runnings.)

Another thing to consider is that those braided lines are soft and may compress under a lot of grain. I use an inverted, stripped down vegetable steamer as a pseudo false bottom. It sits over top the braid to keep that from happening. I recently did a barley wine and sparged 14 gallons for two beers from 27# of grain without a problem.

Title: Re: First stuck mash: batch sparge
Post by: denny on January 06, 2010, 03:28:27 PM
FWIW, I've done 365 batches with the same braid and never had a stuck runoff, although I crush very fine.  The braid has also never collapsed, even with 75 lb. of grain.
Title: Re: First stuck mash: batch sparge
Post by: mrdrysdale64 on January 06, 2010, 06:37:02 PM
I do not know if it would work on a braid manifold but I use cheesecloth on my false bottom as a little extra insurance against stuck mashes. Never had one! Seems like a single layer wrapped around the manifold might help?
Title: Re: First stuck mash: batch sparge
Post by: beer_crafter on January 06, 2010, 08:28:06 PM
Does anyone use Hi-Temp vinyl tubing?  The ID is 3/8" while the OD is 1/2".  I recently changed to this from regular 1/2" OD vinyl tubing and I noticed my flow during the sparge got significantly slower, which in retrospect, is an obvious result.

When I removed this from my tun, replaced it with the regular 1/2 OD" and that allowed me to drain the mash. 

I am wondering if a tight crush along with the Hi-Temp tubing combined to create the stuck sparge.

Now...  is it OK to use regular vinyl tubing at mash temps?   I originally switched to the Hi-Temp stuff mostly becuase the regular stuff collapses and suctions in on itself when hot.. but it sure doesn't ever result in a stuck mash!  Is there a better tubing to use for this application?

 
Title: Re: First stuck mash: batch sparge
Post by: bspisak on January 06, 2010, 08:43:15 PM
Most of the clear vinyl tubing I've seen at hardware stores is rated to 175F which should be fine for mash temps. In fact, I've been using this for a steam infusion line (250F) and it has held up for a couple of mashes, though it will need to be replaced soon with something better.

Not sure what tubing you're using, but it doesn't sound like it has a very good temp rating.  Some of the stuff I see from Micromatic and elsewhere is rated to 212F and folks use it in their recirc systems.

I just read somewhere that if you start your run-off too quickly, it could create a vacuum and compact the grain bed. Sounds like using smaller diamater tubing is the opposite of that.
Title: Re: First stuck mash: batch sparge
Post by: dhacker on January 06, 2010, 08:45:31 PM
I'd try at least adding enough foundation water initially to cover the braid before you add any grain. I think hokerer is probably onto something with the doughball theory. Same could have happened even in the second tun without any foundation water to break up the wad of goo..
Title: Re: First stuck mash: batch sparge
Post by: ndcube on January 07, 2010, 07:46:08 AM
Do you know the gap of your mill?  I would check your crush first.

I used to add water to the grain and never had any problems other than it was a little more work.
Title: Re: First stuck mash: batch sparge
Post by: beer_crafter on January 07, 2010, 09:22:51 AM
I don't.  Going to measure it once I get a feeler gauge this weekend.
Title: Re: First stuck mash: batch sparge
Post by: stout_fan on January 08, 2010, 07:31:50 AM
My system is set up to use QDs on everything, So when mashing in I just pump from the HLT to the tun and underlet the grain.
Instead of having surface tension work against you and create doughballs, use capillary action to wet the grain. When I used to dump the grain in, I always had doughballs. Now, I never do.

Now when doing a high wheat or oatmeal beer I have had a stuck sparge. A LHBS manager gave me this tip. In my case the tun has a male QD fitting on it. So he said basically just give the tun a BJ.  :o

I take a connection hose with female QDs on it and connect to the tun. Then just blow into the hose and it will lift the grain bed. Be sure to be above the level of the liquid and kill the tun outlet valve when you think you have blown enough air into the tun. Then vorlauf again.

Sorry for the description, but it works. Just never admit in it public. :D
Title: Re: First stuck mash: batch sparge
Post by: bspisak on January 08, 2010, 09:02:51 AM
Another suggestion I've heard is to run some tubing from the dead space at the bottom of the tun to the top in order to prevent a vacuum from forming.
Title: Re: First stuck mash: batch sparge
Post by: beer_crafter on January 08, 2010, 09:51:46 AM
Doughballs aren't the problem.  The mash itself was quite well mixed and even rather thin. 

Title: Re: First stuck mash: batch sparge
Post by: rabid_dingo on January 10, 2010, 07:48:44 AM
I have had a couple of stuck mashes and being that the mashing process should be done(in theory) I have no
problem shooting some water up the hose in reverse...I use some garden implements in my brewery (Gasp!)
I use the jet setting on the mutly tool and it usually stirs the bottom of the bed enough to re-vorlauf into a
nicely draining grain bed...
Title: Re: First stuck mash: batch sparge
Post by: zee on January 13, 2010, 11:38:15 AM
FWIW, I've done 365 batches with the same braid and never had a stuck runoff, although I crush very fine.  The braid has also never collapsed, even with 75 lb. of grain.

personally, i think there are so many things you changed here that it's hard to put your finger on which one it was that caused the stuck mash. i'd try each thing separately and see what happens on future batches.

with that said, i think both the things you did could lead to a stuck mash. the finer the grind the more likely you are to plug up all the holes in your ss braid.

secondly, i would think that dumping the grain on the braid could crush it more easily than putting the water in first. since the grain won't get into the tube its just going to sit as dead weight on it, potentially squashing it a little. add the weight of some water, and it could definitely distort. the other way around, when you add water first, you can be certain that the braid is not deformed since the water can pass readily through the holes. when you add the grain it won't go shooting to the bottom, it will slowly drop as it soaks up water, so likely it will pile up around and on top of the braid in a more gradual manner helping prevent any distortion or smooshing. as in your second try, dumping mash on top of your braid, i would think again, could squash it due to the weight of the wet grain and water hitting the braid.

so in short, i'd advise adding the grain to the water in the future, as in my mind the other way around seems likely to cause problems.
Title: Re: First stuck mash: batch sparge
Post by: denny on January 13, 2010, 12:05:17 PM
so in short, i'd advise adding the grain to the water in the future, as in my mind the other way around seems likely to cause problems.

To clarify my post, this is what I do.
Title: Re: First stuck mash: batch sparge
Post by: yugamrap on January 14, 2010, 07:33:05 AM
I've had a couple very slow run-offs where the problem was that doughy/pasty protein, called "teig," that you saw on top of the grain bed.  In both cases, the teig was so dense that the wort was just sitting on top of it and not flowing down through the grain bed.  The solution for me was to "cut" the grain bed while sparging.  I use the edge of a long spoon or my mash paddle and cut down through the grain bed in a criss-cross pattern.  As long as you stay an inch or so above your braid (or manifold in my case) as you cut, there will still be an adequate filter matrix at the bottom of the tun and the runnings will stay clear.
Title: Re: First stuck mash: batch sparge
Post by: nyakavt on January 14, 2010, 08:43:54 AM
To the OP, I had similar problems with certain mashes getting stuck or flowing very slowly using cooler and braid system.  Looking in the MT, you could see water sitting on top near the edges of the cooler (furthest from the braid).  I think this is due to the very tight crush you used.  The braid may not be able to handle such a fine crush from certain mills, as Denny seems to have no problems with it, but I did.

My barley crusher was set at .025" and I almost always had issues on the first runoff.  Since then I started conditioning the malt before milling and it solved the problem completely.  You could also use rice hulls, or open up the crush a bit.  Even raising the temperature before runoff may help, as I never had problem on the sparge, but I would typically not do this for first runnings.

If you don't have gauges you could try a credit card, they are around 0.030" according to the ones in my wallet.  If that won't go between your rollers, you are probably crushing fine enough to notice problems, at least if your system is similar to mine.
Title: Re: First stuck mash: batch sparge
Post by: beer_crafter on January 18, 2010, 08:10:22 AM
Opened up the gap on the mill to the same width as a credit card (about .030") and my latest mash was much better.  There was very little teig on top of the grain. Still using regular tubing, next step is to try with the hi-temp stuff.
Title: Re: First stuck mash: batch sparge
Post by: zee on January 18, 2010, 12:40:27 PM
you've got to also take into account the speed at which you are milling your grain. if you're going at hand crank speeds you're going to get a very different crush than you will at high speed drill speeds, as at high speeds it will tend to rip and tear the husks more.