My water is very soft (low carbonates) and very low in natural calcium (which is needed in the mash to help the pH and also added to the boil to aid clarity/hop extraction etc.) Adding a teaspoon of gypsum to the mash and a teaspoon to the boil puts the minimum level of calcium needed into MY water profile for the style of beers I like to brew. You may or may not need to add it at all (get a detailed water quality report from your local water board)phatboytall wrote: whats the purpose of gypsum?
Plasterboard is technically the same stuff as gypsum but I wouldn't try using it in your beermaking. Plaster from British Gypsum contains perlite and vermiculite (amongst other things) which as far as I know are poisonous if ingested (read the label on the back) You can buy a tub of brewing gypsum for about a quid from Hop & Grape.phatboytall wrote:I have a bag of this in the garage from plastering my bathroom, is it the same stuff?
Kev
