Beta Glucan Rest

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Ringwood, Melbourne
Hay Folks... I keep looking at the beta glucan slot on the probe in the MT and wondering if it is worthwhile adding this step?

Im generally doing this

50-52 - 10 mins
64-65 - 30-40 mins
70-72 - 10 mins
77 - 10-15 mins

Yet to taste the results of any of this step mashing malarky but it sure is fun and the system is working well so Im just wondering if adding the BG rest will add anything.. I did search a bit but found nothing concete about it being required/advised these days.

Cheers all

As far as I'm aware, the main benefit is degrading some of the proteins that may glug up your manifold and is useful is using something like rye in large proportions.

Coincidentally the temp range sits somewhere between traditional acid and protein rest and so if you were to rest at 45, you would presumably be slightly acidifying the mash and slightly degrading other proteins as well as degrading the b-glucans. I believe b-glucans can contribute to haze etc but modern modified barley malt shouldn't contain excessive levels.

Not sure if you'll notice a whole lot of benefit if just making an entirely barley based beer and if you're wanting to work out what steps do what in terms of final product, probably best to reduce the number until you are satisfied they are effective/useful.

Thirsty Boy or MHB will probably have some better/more detailed info - that's just my understanding and the only time I've incorporated a b-glucan rest was for an all oat malt beer - something that may not have been necessary anyway (beer has turned out tasty though)
If you are using modern fully modified malt its probably unnecessary.
When you use adjunct, less than fully modified malt or malts with high Glucan content (Im going to include any of the floor malted offerings on the market) then yes I would seriously consider a B-Glucanase rest.

Analogies are always a bit suspect - but If you think of the grain as a lump of concrete if you wanted the aggregate out of concrete you could dissolve the cement with acid
Think of the starch granules as the lumps of rock, the B-Glucan would be the cement, to allow the saccharifying enzymes to get at the starch we need to break down matrix and B-Glucanase does the job. Fully modified malt will have the matrix fully broken down during the malting process (sort of the definition of fully modified) if you are not sure, chew some of your malt, the term used is ball-bearings, its fairly unmistakable and feels just like you are trying to chew rocks.

Having said the above, if your system has the ability to include a couple of extra steps without too much grief why the hell not do them.
B-Glucanase like a fairly acid environment, if you were trying to chew through a lot of adjunct it might be worth tweaking your pH to just under 5 and then readjusting before heading up to higher rests.

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