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Protein Rest for Unmalted Grains

Reading the thread of the fellow who had a sticky mess mashing 100% rye, and given a link to How To Brew, which I’ve read through several times, but have issues fully understanding the mash, I’m reading about the protein rest necessary for unmalted grains.

In HTB it’s stated that:
“Fully-modified malts have already made use of these enzymes and do not benefit from more time spent in the protein rest regime. In fact, using a protein rest on fully modified malts tends to remove most of the body of a beer, leaving it thin and watery.”

Is it then best to steep these types of grains separately for the 20-30 mins and then add them to the grain bag to mash (doing BIAB)?

And does flaked corn need this too? Rice?

He goes on to say:
“The typical Protein Rest at 120 - 130°F is used to break up proteins which might otherwise cause chill haze and can improve the head retention. This rest should only be used when using moderately-modified malts, or when using fully modified malts with a large proportion (>25%) of unmalted grain, e.g. flaked barley, wheat, rye, or oatmeal. Using this rest in a mash consisting mainly of fully modified malts would break up the proteins responsible for body and head retention and result in a thin, watery beer. The standard time for a protein rest is 20 - 30 minutes.”

But then says:
“Fortunately, the optimum temperature range for the beta glucanase enzyme is below that for the proteolytics. This allows the brewer to rest the mash at 98 -113°F for 20 minutes to break down the gums without affecting the proteins responsible for head retention and body.”

I’m a bit lost as to which protein rest I’d need if using 25%+ of unmalted grains.

And is this protein rest the same a response that speaks of:
“Try another rye beer but this time, do a beta glucan rest at about 104F for 20 to 30 minutes to break up the glucans.”

Also from HTB:
“The temperature and pH ranges for these two proteolytic enzymes overlap. The optimum pH range is 4.2 - 5.3 and both enzymes are active enough between 113 - 131°F that talking about an optimum range for each is not relevant. This optimum pH range is a bit low with respect to most mashes, but the typical mash pH of 5.3 is not out of the ballpark.”

And so how is this effected if my mash is of a higher pH such as 5.5 or so?

Here are several of my upcoming brews (the oatmeal stout ingredients are on the way and the others are for next month):

Oatmeal Stout:
1.5 lbs oatmeal (Quaker) 14%
1 lb flaked barley 9%

As this is just below the 25% where it’s said both a protein rest and betaglucanase are needed should I do them anyway?

Rye Pale:
2.75 lbs Briess malted rye 27%
0.75 lb flaked barley 7%

As the rye has been malted do I need to do a protein rest?

Hoppy Wheat:
3.25 lbs malted wheat 33%

Again it’s malted as with the above rye. Protein rest?

Cream Ale:
1.5 lbs flaked corn 16%
1 lb flaked barley 11%

Does flaked corn behave the same way as other flaked grains and therefor need a protein rest? What of the betaglucanase rest?

I stopped doing a protein rest a while ago. I’ve tried it both ways multiple times and I didn’t find it was worth the effort. My most recent batch included 55% wheat (half flaked). I used 1 oz of rice hulls per pound of wheat. No issues at all.

I don’t know how experienced you are as a brewer, so I will say generically that there are far more productive things for brewers to focus on mastering (water chemistry, yeast health, fermentation temp, sanitation, etc.).

I figure myself as an intermediate brewer. I BIAB.

I have been doctoring my water for several months now as I understand it somewhat enough to feel confident enough to dabble, though I’ve only recently seen the actual effects on pH as I had been using a more basic water calculator.

Sanitation is great, and I have a fermentation chamber. I ferment at 64* for 7 days and allow to rise to room temp (~73*) for the other 14 days. I made yeast starters and saved portions of yeast for a few years until I lost track of how many uses I had and was moving and wouldn’t be able to brew so I dumped them. Since then I’ve been using dry and rehydrating.

I feel mashing and water are the bigger areas (outside of experimenting with more yeasts and grains, and styles).

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