Bob der Braumeister
Join Date: Aug 2005
Location: Tallahassee, FL
Water and Homebrewing
What do I need to know about water before I make my first beer?
Does your water taste good? If so, it will make good beer. If not, you should use bottled water instead.
Can I brew with distilled water?
Most homebrew websites say, “No,” but I vigorously disagree. The argument is that yeast need certain micronutrients like zinc and copper that are missing from distilled water. I have brewed with distilled water many times, and have never had a problem. I also discussed this with my father, who is a Ph.D. biologist with 40 years’ experience with yeast. He says that the grains used to make wort and extract provide all the micronutrients your yeast need. There are times when distilled water is the best thing to use (keep reading to find out when.)
If I’m ready to start thinking about how my water affects my beer, what do I need to know?
There are two chemical characteristics of water that significantly affect beer, pH and hardness. Let’s take them one at a time.
What do I need to know about pH and beer?
The ideal pH for making beer is 5.2. This is especially important for all-grain brewers because the enzymes that convert starch to sugar are pH-dependent. Most of the time, if your water is not an ideal pH, it is too high, which can be corrected with brewing salts or buffers. Brewing salts will make your water harder, and I have never brewed with buffers, so I can’t say much about them.
What happens if I brew with water that has a pH higher than 5.2?
You’ll lose some conversion efficiency (in other words, less starch will be converted to sugar.) If you were a commercial brewery this would drive you mad, but homebrewers don’t normally sweat it that much because you can just add a little extra grain. I have brewed with pH 7.0 water, and I could notice an efficiency drop, but it did not ruin the beer by any means.
So, for the homebrewer, pH is less important than hardness?
In my opinion, yes.
How can I reduce my pH?
Adding brewing salts. Most commonly these are calcium sulfate (gypsum), calcium chloride and calcium carbonate (chalk). The calcium ions will reduce the pH.
How does hardness affect beer?
Briefly, hard water is going to make beers darker and make bitter flavors from the hop more noticeable. Soft water makes lighter beers and reduces apparent bitterness, which has the effect of increasing the non-bitter flavors (the aromatic and “sappy” flavors) of the hops. It’s going to be pretty much impossible to make an authentically pale pilsner with hard water.
How is hardness measured?
Hardness measures the amount of calcium and magnesium in the water. Brewers often use German hardness (G), and water quality reports usually use mg/L. To convert, divide the mg/L by 18 to get G. My water is 156 mg/L total harness or nearly 9 G. Water under 3.5 G is considered soft. Water over 7 G is considered hard. Water over 12 G is rarely used to make beer.
What is the difference between temporary, permanent and total hardness?
Temporary hardness is connected to the concentration of carbonate and bicarbonate ions. These ions form a solid precipitate when heated. If you have white scale on the bottom of your pots, you probably have a lot of temporary hardness. Boiling water that has a lot of temporary hardness will make it softer (though it rarely removes all of the temporary hardness.) Permanent hardness is connected to sulfate and chloride ions. Those compounds do not boil out. Total hardness is simply the sum of the two.
Do temporary and permanent hardness affect beer differently?
Yes. Temporary hardness will have a strong effect on color because you are extracting most of your color around 150 F. It has a moderate effect on bitterness because much of the hardness leaves during the hop boil. Permanent hardness will strongly affect both color and bitterness.
How do I determine my water hardness?
If your water is supplied by a utility company, call them. They have the numbers. If you use well water, you will need to get your well tested. Be aware, some places, especially in the SW US have ultrahard water that can hit 55 G, and is not suitable for making any kind of traditional beer. Furthermore, if you can taste iron in your water, don’t use it.
Is there a connection between hardness and beer style?
For many regional styles, yes. Pilsners are brewed with water that is only about 1 G, as the water in Pilsen is extremely soft. Stouts are typically made with water around 10 G, because Irish water tends to be very hard. English bitters can go either way. Southern and Eastern England has water that is 10-12 G, while Northern and Western England and Wales has water that is under 4 G. Austrian beers are made with some of the hardest brewing water in the world—12G at most major breweries, and even harder at some regional operations. It’s best to think about what you want out of your beer, and adjust your hardness that way.
How do I make my water harder?
Add brewing salts. To add temporary hardness, use calcium carbonate (chalk). To add permanent hardness, use calcium sulfate (gypsum) or calcium chloride. Remember that all of these will also reduce pH.
How do I make my water softer?
Either use all distilled, and add brewing salts to achieve the desired hardness, or dilute your local water. I know my local water is 9 G, so if I use 1 gallon of my water and 4 of distilled, my hardness will be 9/5 or 1.8 G.
How does water hardness affect recipe design?
If I want pale beer, or lots of hop aroma, I use soft water. I often use hard water when I don’t want much hop aroma (like when I am making an Austrian or German lager.) Because hard water increases apparent bitterness, I can use fewer hops in a hardwater beer to hit my IBU target, and it keeps the hop flavor down. I am a malt head, so I brew most of my beers with water that is 12 G total hardness, of which 4 G is permanent.
How much brewing salt do I need to use to add 1 G of hardness to my beer?
Calcium chloride: 0.18 g/gal
Calcium sulfate (gypsum): 0.23 g/gal
Calcium carbonate (chalk): 0.17 g/gal