Decoction question

[ghank15]

Ok. So I read up on decoction mashing and I understand the procedure(sort of) and concepts behind the process(well, sort of).

But, how do you avoid extracting tannins if you are boiling 1/3 of your mash a few times then adding the 212 degree concoction to the rest of your mash?

For reference, I haven't done any all grain batches yet (doing my first single infusion later in the month) and I have done one partial mash. I am just very interested in this process.

 

[Skyforger]

I think tannin leaching is an exaggerated problem. Decocted beers turn out very smooth (all other things being equal) despite the issue you mention.

I believe tannin leaching is more of a problem in the sparge anyways, as they are extracted more readily into water that's not already full of sugar and acidified by the mash. The higher the pH, the more tannins you get.

So it might be a problem if you're doing a light (color or gravity) beer, have alkaline water, and aren't compensating for that in any way.

 

[LKABrewer]

As long as the pH of the mash is in the 5.2-5.6 range, you will not extract tannins, no matter what the temperature is. If you are sparging too hot, and the sparge water is too high in pH, you will extract tannins.