Interesting boiling article

Australia & New Zealand Homebrewing Forum

Help Support Australia & New Zealand Homebrewing Forum:


BrewInn Barossa:~ Home to GMKenterprises ~
Reaction score
Boiling Grains

I have just done a Grumpy's Theakstons Old Peculiar Kit.

Part of the process involved boiling the Grains contained in the Kit for 35 mins before straining into the fermenter.

I have followed their method and the result is fermenting well with S04 yeast.
I tasted prior to yeast was nice with no noticable tanins.

However, Grumpys is the only people so far (that i have found) that advocate that it is all right to boil grains.
Everywhere else thay say not should only steep them...

What are other peoples opinions regarding boiling grains. Good or Bad....


Well-Known Member
Reaction score
This is a very interesting area and relates to a discussion I've been following on the craftbrewing discussion list. Decoction mashing involves removing some of the mashed grains in a small amount of liquid, boiling then returning to the tun. If boiling in its own right brings out tannins then decocted brews should be harsher than single infusion - but I've read that this is not the case. Rather decocted brews may well be smoother than single infusion mash brews.

One explanation I read relates to mash ph. I'm a bit vague on this but from what I remember - so long as mash ph is below 5.7 or so, tannins won't be extracted. So when mashed grains are removed from the tun for decoction - because only a small amount of liquor is removed at the same time the ph lowering effects of the grain are in a sense magnified (as there's a much greater grain to liquor ratio).

ie if it's PH level that determines tannin extraction rather than boiling, then boiling is fine so long as ph is ok.

It's an interesting argument since I have often read never to boil grains. I think I've correctly represented the above argument but am happy to be corrected.


Latest posts