I have once again brewed extract batch of I.P.A. that has finished with a harsh astringency. I came across this thread http://www.homebrewtalk.com/f37/attention-all-extract-brewers-harsh-bitterness-aftertaste-128731/ with many other people discussing the same issue. Chris Colby was quoted in the thread (post #25) with his method for steeping specialty grains…
“Start with 1 gallon of Campden treated RO water and 1 tsp. of 5.2 pH stabilizer in the kettle. Stir in 1 lb. of dry extract while heating to 165*F. At 165*F remove from heat. Drop in the steeping grain bag, tea bag it to get the grains wet and let it sit 30 minutes. Steeping in a small volume with pH stabilizer and extract keeps the pH around 5.2 which will prevent extracting tannins from the grain husks, which is the most common off flavor in extract beers. Drop a strainer over the pot and move the grain bag to the strainer. Run your top-off water slowly over the grains to rinse them until you get to your desired boil volume. Stir in 1/3 of the remaining extract for a partial boil, or 2/3 if doing a full volume boil, and bring to a boil. Add your bittering hops. With 15 minutes left in the boil, add a whirlfloc tablet, yeast nutrient, and the rest of your extract (do this off the heat so you don't scorch of course!). Stir continuously while chilling until the wort drops below 140*F.”
I would like to try his method but have a few questions for anyone else who has tried it, or someone familiar with the technique.
1) Since I am treating the steeping water with campden and 5.2 stabilizer, wouldn't I also need to treat the top off water the same? The RO water would likely be 7 ph or higher wouldn't it be?
2) If I am using R.O. water why am I treating it with campden? Isn't campden intended to remove chloramine? Wouldn't R.O. water be free of chloramine?
3) Why does he suggest stirring continuously till 140* is it simply to more evenly and quickly chill the wort, or some other reason related to his technique?
4) Since I am brewing an IPA, can I still use gypsum in my boil to help with hop character while using this method?