Dear Mr. Wizard,
I have been brewing for more than seven years now, mostly using extracts and specialty grains, with excellent results. I use city water, which runs through a water softener and charcoal filter to remove the chlorine. You’re probably thinking, "Softened water and all those sodium ions — your beer probably tastes like the ocean!" Actually, I use potassium chloride in our water softener instead of sodium chloride. The potassium chloride is readily available in our area as a substitute for more traditional softener salt and is advertised as a healthier alternative to humans and plant life. Are the potassium ions present in my brewing water a desirable addition?
Scott A. Howard
Mr. Wizard replies:
Potassium chloride is commonly sold as an alternative to sodium chloride. Those companies that market potassium chloride make the point that it doesn’t do all the terrible things to the body that sodium does and that potassium is necessary for the body to properly function. Potassium is indeed required by the body, but sodium is also required. Both are integral parts of the sodium-potassium pump that maintains a membrane across the cells of the body. Anyhow, most diets supply ample potassium and sodium, and few Americans need to supplement their diets with either of these elements.
The heart of the matter lies in what effect, if any, potassium has on beer. Yeast cells do not require any dietary supplements of potassium, and the potassium does not affect mash pH like calcium, magnesium, and carbonate do. However, potassium chloride does have a salty flavor similar to the taste of sodium chloride and also has some metallic flavor notes. These flavors will find their way to your finished beer if your softened water has a high concentration of potassium.
In general I do not suggest using water from salt-based softeners for brewing — or drinking for that matter — because the water usually tastes funky. The primary use for these water softeners is to remove calcium and magnesium hardness that react with carbonates to form scale in pipes, water heaters, and dishwashers. Soft water also works better for doing laundry and lathering up the body in the shower. None of these things has anything to do with brewing an excellent beer or producing a pleasant-tasting glass of water. In fact certain key minerals, especially calcium, that are very important to mashing, trub formation in the boil, and yeast performance are the same minerals removed by salt-based water softeners.
Many of the most prized brewing centers in the world have very hard ground water. Burton-on-Trent, Dublin, London, Edinburgh, and Munich all are hard-water towns. Certain types of beers such as pale ale, stout, dark lager, and other similar styles turn out quite well with hard water. Light beers such as pilsners usually turn out best with soft water and the brewers of Munich do not use its famed "dark lager water" for brewing their light lagers.
The point is your city water may be great brewing water without any treatment except for the removal of chlorine with a charcoal filter or heat. I would get my hands on a water analysis and a good article on brewing water to help decipher the analysis. If you still want softer water after reading the analysis, consider some other techniques such as boiling or buying bottled drinking water. Softened bottled water is treated with other techniques that leave very little in the water but water! Bottled water usually works best for brewing if you add some calcium sulfate (gypsum) or calcium chloride.
Dear Mr. Wizard,
I brewed an imperial stout, and after the primary fermentation was complete, probably a month ago, I racked the stout into the secondary. And there it remains. I got so busy with other things I kind of forgot it in the corner of my wife’s kitchen. I do not want to discard it. The airlock is still in place, and there are still small bubbles rising to the top. Will I need to do anything different than the normal priming and bottling?
Mr. Wizard replies:
Many beers, especially big beers such as imperial stouts, mellow with extended aging in the secondary fermenter. It is usually best to place the secondary in a cool place for extended aging to prevent excessive yeast autolysis and to stunt the growth of bacteria that may be slowly growing and contributing funky flavors to your beer.
Your beer has only been in the corner of the kitchen for a month, so it probably is still okay. The best thing to do before considering discarding a brew is to take a sample of the beer and taste it. If it tastes like good beer, then continue to the next step and don’t worry too much.
Depending on the type of yeast you used and the temperature of your wife’s kitchen, the beer may have very little yeast left in suspension. Visual inspection in a very thin glass will give some insight into how much yeast is suspended in the beer. Another point to keep in mind is that the yeast that is in solution may not be in great health. If the beer seems extremely clear or if you feel the yeast may be cranky, you may want to add some yeast to ensure proper carbonation.
The actual amount of yeast required for conditioning is extremely small, about one-tenth the amount required for pitching. Although I recommend using liquid yeast for pitching wort when possible, dry yeast works very well for bottle conditioning. Let’s face it, all you really want the yeast to do is to cough out a little carbon dioxide and then sink to the bottom and keep quiet! As long as you choose a brewing-quality dry yeast, you’ll be fine.
When using dry yeast it is always best to hydrate the yeast in boiled and cooled water before use. The easiest way to measure out a very small quantity of yeast into your bottling carboy is to hydrate a whole pack of brewing yeast in a known volume of water; eight ounces works well. Then use about one ounce (about two tablespoons) of the slurry per five gallons of beer for conditioning purposes.
If you decide to go to these measures to ensure proper carbonation, be sure to mix the yeast slurry and priming sugars evenly in the beer prior to bottling. If the beer still tastes good on bottling day, your unintentional neglect shouldn’t cause any future problems.
Mr. Wizard, BYO's resident expert, is a leading authority in homebrewing whose identity, like the identity of all superheroes, must be kept confidential.