SpillsMostOfIt wrote:I think the over-crushing leading to tannin extraction argument is flawed. If over-crushing led to tannin extraction, then tannins would come out regardless.
I think pH is probably a more likely culprit. But, I am a failed scientist...
(snip)
FWIW I agree with you SMOI - temperature and pH are the two culprits, IMO. And this is one reason why I never bother trying to scratch anywhere near 100% efficiency with the sparge - I'm happy with the full flavoured beers that I can happily make with around 75% to 85% efficiency. All I'd be doing if I tried to sparge the bejaysus out of the mash would be to push the pH up and encourage the extraction of polyphenols from the mashtun resulting in hazy beer.
If you want full flavoured beer, leave the Gypsum on the shelf and lash out with an extra kilo of base malt in the recipe!
Cheers,
TL