Yesterday I brewed a wheat IPA [55% Rahr 2-row/45% wheat] for the second time and I had a very “interesting” experience. First, The boil produced an outrageous amount of foam. Second, my hop basket[/url] clogged and kept dancing around in the kettle resulting in mini-boil-overs ([url=http://s564.beta.photobucket.com/user/kcbeersnob/media/Brewing/VIDEO0023_zps66889601.mp4.html]Here’s a video in case you can’t visualize what I mean]
. Third, the amount of trub left in the kettle was pretty staggering.
I’ve got two theories and wanted to run them by you all.
I crushed my wheat malt too fine and ended up with a ton of flour and/or the flaked wheat had excess flour. I didn’t notice an unusual amount of flour and didn’t have any lautering problems.
My mash temp ended up settling in at 147.7°F. Long story short: I did a two stage rest and my second infusion was a little lower than it should have been. I figured it was close enough, so I let it ride. I’ve never mashed that low before. Does something happen during conversion at ~148°F that that would explain the unusual experience I had in the kettle?
Too fine a crush would cause lauter problems and perhaps astringency problems, but the flour should have converted to sugar. That mash temp should have been fine; its going to give you a drier beer, but that’s probably what you want in this style. Wheat tends to give a lot of foam, which is good for finished beer but a headache for the boil.
This was a very odd experience. I didn’t have these problems when I brewed the recipe in early December. Only two differences this time were a scaled up grain bill (same ratios, but increased quantity) and the lower mash temp. The last batch had very good head retention.
I’m sure the beer will turn out fine, although hopefully the clogged hop basket didn’t diminish the hop utilization too much.
I just rebrewed this recipe yesterday, this time taking my mash pH. It was spot on at 5.36 (aiming for 5.4). Same horrible experience as last time, but with a bit less foam and trub (but still a lot).
So now I’ve brewed this recipe three times. First time no problems at all. Second and third time were as described in my OP. The only differences that I can identify between the first and subsequent times are:
Grain bill one pound heavier on 2nd/3rd batch to increase the OG
Sach. rest temp first time was ~152. Second time was ~148 and third was ~149.
I did not mention previously that the grain bill is 45% wheat (27.5% unmalted). I’m thinking something must be happening in the mash enzyme-wise with that much wheat at the lower temp, producing the extra solids.
Yesterday I brewed a different recipe with 40% wheat (this time, the majority was malted red wheat). To rule out mash temp as the cause of my prior problems, I mashed at 154°F. I had similar problems, although not as pronounced–probably because this was a low gravity beer. As the volume in the kettle dropped, the hop basket dancing really picked up. I feel comfortable saying that mash temp is ruled out.
The big problem this time: the wort scorched under the basket. I’ll probably have to dump it like I did after fermenting the batch that prompted this thread.
I’m leaning toward: this is to be expected when brewing with a high % of wheat; therefore, I need a different solution for hop filtration. Or I suppose I could look into step mashing to break down beta-glucans and long chain protiens to see if that helps, but that seems like a PITA.
First, ignore my comment from the General board thread.
Second, I wonder if it something about wheat in general and the proteins in solution. The process of boiling and the liquid pressing through the fine mesh could be creating a great deal of foam around the stainless screen, which then sends the screen buoyant and it dances around. This would have to be unique to the chemistry of a heavy wheat wort for this to make sense.
So, either weighing the screen down (with the spider top or some sort of stainless weight in the screen) or clamping it to the kettle might allevate the scorching problem, or clamping it high enough that there is plenty of room for liquid to fill in under the foam that forms.
[quote=“alphastanley”]First, ignore my comment from the General board thread.
Second, I wonder if it something about wheat in general and the proteins in solution. The process of boiling and the liquid pressing through the fine mesh could be creating a great deal of foam around the stainless screen, which then sends the screen buoyant and it dances around. This would have to be unique to the chemistry of a heavy wheat wort for this to make sense.
So, either weighing the screen down (with the spider top or some sort of stainless weight in the screen) or clamping it to the kettle might allevate the scorching problem, or clamping it high enough that there is plenty of room for liquid to fill in under the foam that forms.
Cheers.[/quote]
I’ve done 10 batches with my basket now. The hop basket has worked great in all cases, except those with a large percent of wheat. Having done some reading earlier today, I believe it has to do with the long chain proteins and/or beta-glucans in wheat.
I’ve already been in touch with the guy who makes these baskets to build another unit that should overcome both of the problems I’ve experience due to the unique characteristics of wheat. He’s going to build a new basket for me with 300 micron mesh instead of 400. He’s also going to configure it as a spider-basket, so it will be suspended above the floor of the kettle and the heavy stainless collar on top will weigh it down. I think I’ll be good to go after that. I just hope I don’t have to wait a month.
Yes its all about the wheat. Its the reason they use 5% in a lot of recipes for the head-promoting proteins. You get more foaming during boiling and more krausen during fermentation with wheat beers.
