Wheat Mash Problems
Recently we have had problems brewing one of our wheat ales contain about 50% white wheat. A few times whe have almost stuck the mash. Also while emptying the Mash Tun we have found sweet clumps of malt which would explain the lower O.G. We are using rinsed rice hulls and mash temps about 140F. Our sparge is closer to 170F.
Is this simply a temp. issue, possibly too little water in the mash. Or is the mash just not being mixed and hydrated enough?
Thanks for any tips
Sounds like you may be milling your wheat too fine and or getting a bad mix out of your fore masher.
Rice hulls?....are your batches larger than 20bbls.?
How long do you mash?
I have been entertaining the idea of making a wheat beer on a 7 BBL system. I'm wondering if rice husks are necessary and if so, at what stage of the mash they should be added, and how much should be added.
Also, is it better to mash at a higher temperature to avoid a possible stuck mash?
Thanks for any advice!
I've been brewing a 50% wheat recipe for 15 years on 12 different systems in 4 different scales; 7-10-14-20.
With wheat,..there's often a fine line,unique to each mash tun with how "fine" to mill it.
Providing that your mash tun is of 2-to-1 ratio in dimentions,you shouldn't need any "flow mediums"(rice hulls) up to at least 400lbs. in a 50/50 recipe, and still get at least a 90% extract efficancy.
Other potential variables include;
Mash screens: "v" wire is better than perforated.
Mash temp: 152-6* should cover everything enzymacly.
Mash time: another fine line, no more than an hour should cover everything. Avoid recirculating the wort much ,if at all.
Alot of small variables are going to be unique to you brewery equipment configuration.With wheat,I found, most stuck mash nightmares start at the mill. You'll just have to fine tune it for your system.
I wish you much luck.
The sweet malt clumps are a common occurence related to lack of water during mashing. We refer to these as malt-bergs. You can avoid this by increasing your mash foundation water. I would suggest mashing at a higher temp, 156F or so. The viscosity of the wort will be less with higher tempertures. Do you have the ability to measure DP? Try calculating you water:grist ratio as well. It can really vary depending upon systems. Generally 2.5:1-3:1 works well. We brew about 100,000 bbls. of Hefe a year on a four vessel system. The grain bed is relatively shallow at 12-14 inches. No hulls are needed. Your mash time should be determined based upon conversion; mash pH or iodine reaction. I think you should recirculate, we vorlauf for approx. 20 minutes. If we do experience more deepcuts (to avoid stuck lauter) than normal it generally means we've had a shift in our malt parameters or a new crop has been delivered recently. We then fine tune the system recipe. Best of luck.
We are brewing on a 14bbl system and we use premilled Cargill White Wheat, still haven't installed our milling system. Our mash-sparge time has been about an hour to an hour and a half, including a 30-40 min recirc.
From the responces i have read, it sounds as if we need to get our mill running, hydrate our grain more efficently (which has been a personal concern of mine) and shorten our mash and recirc. times.
BTW, anyone had any experience with backflowing the mash tun & re-recirculating to reset the bed of a stuck mash. We had to do it once, just curious how common it is?
First and foremost you will always have better success with a properly adjusted mill onsite as compared to using pre-milled grain. We sell pre-milled malt because some brewers simply don't have the money/space/time/desire to buy and install a mill. That being said, pre-milled does work fine in most cases.
With some adjustments you should be able to get decent runoffs in the interim. I concur with many of the statements made thus far. Of primary importance is the mash temperature. Your mash temp. is much too low and your wort will therefore be much to viscous. With your current program I suspect that much of your conversion is going on post sparge when the mash gets closer to 150F or higher.
In addition, a protein rest may help somewhat if this is an option for you. Protein rests (really glucan rests) serve to decrease beta glucan content which results in a decrease in wort viscosity. In either case, only convert for as long as it takes to get starch negative. Sample a few places in the bed at first until you get comfortable with how your brewhouse and malt work.
Minimize recirc, but definitely do some vorlaufing before running to kettle. Your wort will be much too hazy otherwise.
I also agree that rice hulls should not be necessary.
What you are referring to in your follow-up post is underletting. Pumping water in under the screens in order to "re-float" the bed. This is not commonly done on large scale systems but it is rather common on the brew pub scale. Especially when brewing challenging beers like high percentage wheat beers over 50% or very high gravity beers. It is something that should be avoided as it encourages the extraction of undesireables from the malt. Sometimes however, it is the only choice.
And MOST important of all, good call on the wheat malt choice.