I recently finished reading Gordon Strong's excellent book Brewing Better Beer and there were a great deal of useful tidbits and interesting new (to me) techniques presented in the book, but there was one particular part that I think will really bump my beers up to another level. I'm talking about chloramines.
Chloramines are used by some municipal water supplies to disinfect the water going to their customers' homes. Chlorine is also used for this purpose by some municipal water sources, but because people are more sensitive to the presence of chlorine and not as sensitive to the presence of chloramines, in terms of both taste, smell, and feel (dried out skin, etc.), more and more municipalities are switching to chloramines.
The only reason I know anything about this is because I notice the change every year in smell and taste in the tap water when my local water supply switches from chloramines to chlorine to make sure bacteria don't become resistant to it. I know that chlorine is bad for brewing water, since that is spelled out in most introductory/intermediate level homebrewing books and I've read a few of those. I didn't know that chloramines are just as bad and actually probably much worse since chlorine can be removed by simply running your water through a carbon filter (a Brita filter, for example) and chloramines form a stronger bond in water and aren't as easily removed.
This is probably the biggest thing I've been doing wrong with my brewing up until this point. The information on chloramines that I got from my municipal water supply's website said that chloramines are removed by the same type of filtration systems that remove chloramine, so I had no idea that this was not the case and that chloramines were probably the reason my beers always had a slightly astringent off-flavor that I couldn't place. It wasn't too bad, so I suspect that my Brita filter was removing some of the chloramines, but I noticed it and didn't like it.
The solution to this problem is to treat your brewing water with Campden tablets (sodium metabisulfite) to remove the chloramines before adding any malt to the water. The tablets work fast (less than a minute) and one tablet will treat 20 gallons of brewing water.
Although, the book is geared towards advanced homebrewers, I feel like this particular lesson would be useful for all levels of brewers and frankly can't believe that it wasn't mentioned at all in any of the beginner/intermediate books I've read (perhaps an idea for something to add in the fourth edition of The Complete Joy of Home Brewing, Charlie Papazian). So, thank you, Gordon Strong! I've tried this technique in a few batches already and have already noticed that the astringent flavor is gone and my beers are tasting better.
