Seeking permanent haze in a witbier

[milleniarist]

I'm doing my research for brewing a Witbier with 45% heirloom raw wheat and I found this remark in Stan Hieronymus' ´Brewing with Wheat´:

…one study included unmalted wheat, the other malted wheat. In both cases researchers found that haze intensity increased at wheat levels of 15 to 20 percent, then began to decrease with additional wheat additions, so that at 40 percent beer contained almost no permanent haze after just three weeks. The particles obey Stokes’ Law: “Wheat gluten proteins were found to be haze active in that they interact with polyphenols and protein-polyphenol complexes. At low gluten levels, a haze is formed, although at higher gluten levels, these insoluble complexes are too large to stay in suspension and precipitate.” Basically, small particles stay in suspension, while larger ones drop out.

I've had exactly that happening to a saison I made using 20% raw wheat + 20% malted wheat + 5% flaked oats; the haze precititated in the bottle during the conditioning phase and the beer ended up almost crystal clear after some months. I think that amount of solids in the bottle didn't help with flavor stability in the long run either.

My questions are: Would a protein rest at 50ºC / 122ºF help breaking down those proteins to the equivalent of a 15-20% grist? If so, how long should that protein rest be in order to not overshoot it and not having any haze at all or, even worst, damaging head retention? This BYO article claims 30 minutes for 30% raw cereals will produce beer without haze.

Here's my recipe in case you are curious:

OG 1.045
ABV 4,7%

45% Heirloom raw wheat (+13% protein)
38% Weyermann pilsner malt
12% Weyermann pale ale malt
5% Flaked oats

EKG at 60 min for 12 IBU
Coriander seeds + Orange peel + Chrysanthemum in the whirlpool

WLP400 yeast
Fermented at 19ºC / 67ºF

There's so many info out there on permanent haze for NEIPAs and not so much for other styles like witbiers or hefeweizens. I don't want to go the dry-hopping route nor modify the grain bill if possible; I'd like to experiment with this raw wheat since it is a local ingredient and I have plenty of it right now. I'll appreciate any other help regarding brewing witbiers with high amounts of unmalted cereals.

 

[VikeMan]

A protein rest would certainly break down some proteins, and I would say it's worth a shot. Maybe try a batch with a 10 minute rest and another with a 20 minute rest. If one of those improves permanent haze, triangulate from there. i.e. if 10 minutes gives you the better result, try 5 and 15. Or, if 20 gives you the better result, try 15 and 25. You could have this pretty much dialed in after 4 batches.

 

[milleniarist]

Thanks VikeMan, that sounds like a sensible approach. Has anybody tried a similar grain bill and can narrow the ball park down a little bit? Otherwise I'll start with 20 minutes.

 

[couchsending]

Personally I would suggest a long rest at 160-162 (20-30 minutes) over a protein rest. Or you could do both. If it was all barley I’d recommend a rest at 130 instead of 122 but I’m not 100% sure with wheat.

Another trick is to lower the pH of your boil to around 5.0 before it starts. You’ll get less protein coagulation And better haze stability.

 

[Silver_Is_Money]

You may find plenty of good information at this link. One interesting conclusion was that the level of wheat gluten plays a large part in permanent haze. Another was that wheat beers brewed with highly modified malts tend to exhibit increased haze.

https://www.onlinelibrary.wiley.com/doi/epdf/10.1002/j.2050-0416.2004.tb00203.x

 

[milleniarist]

Personally I would suggest a long rest at 160-162 (20-30 minutes) over a protein rest. Or you could do both. If it was all barley I’d recommend a rest at 130 instead of 122 but I’m not 100% sure with wheat.

Another trick is to lower the pH of your boil to around 5.0 before it starts. You’ll get less protein coagulation And better haze stability.

Thank you for the tips! I brewed this recipe last Friday. I ended up doing a 20 min protein rest at 50ºC followed by a mash schedule recommended by Stan Hieronymus in ´Brewing with Wheat´: 30 min at 63ºC, 15 min at 68ºC and 10 min mash out at 78ºC. My efficiency was within my usual values even with such high amounts of unmalted grains.

I may try the 5.0 pH pre-boil next time. On brewday it was 5.5 when the boil started and I got good hot break. I adjusted to 5.0 before knock out.

I put a sample from the fermenter in the fridge and it stays quite hazy. Let's see what happens after a couple of months in the bottle.

You may find plenty of good information at this link. One interesting conclusion was that the level of wheat gluten plays a large part in permanent haze. Another was that wheat beers brewed with highly modified malts tend to exhibit increased haze.

https://www.onlinelibrary.wiley.com/doi/epdf/10.1002/j.2050-0416.2004.tb00203.x

Thanks for the link! It looks very interesting. I'll definitely read it later today.

 

[royger]

Hello,

I'm having similar issues with wheat beers not staying hazy as they should. I've recently brewed a witbier with 50% pale malt, 40% malted wheat and 10% flaked oats and after 2 weeks in the keg at 4C the beer is almost crystal clear, no finings or clarifiers used. I did a single infusion mash at 68C. Did you notice any difference with doing a step mash?

For what is worth I have no issues with NEIPAs staying hazy after months in the keg.