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.”