WATER

Water, referred to by professional brewers as liquor, is the most obvious ingredient of beer. Beer is 90% to 95% water. Although the homebrewer does not need to have a degree in water chemistry to brew properly, serious homebrewers are serious about their liquor. The mineral content of water effects all other brewing ingredients and, therefore, the finished product.

The ions in water have a direct effect on the beer in three ways. First, the ions in water affect the water's pH, which in turn determines the effectiveness of the starch-degrading enzymes during the malting process. (A water's pH is a measure of its acidity or alkalinity. The scale of pH goes from 0 to 14 with 7 being neutral. Water with a pH over 7 is alkaline; under 7 is acidic. A pH of 5.2 is ideal.) This problem does not exist for malt extract brewers as all fermentable sugars necessary for creating a beer are already present in the extract. Second, any flavor in the water effects the flavor of beer. If your water has a "house flavor," your beer will also adopt a "house flavor." For example, highly chlorinated water will impart a chlorinated flavor to the beer. Lastly, water provides nutrients to yeast. Since yeast only requires trace amounts of these necessary ions, this is not a homebrewer's greatest concern.

Most tap water is suitable for basic homebrewing. The rule of thumb is that if it's good enough to drink, it's good enough to brew with. Municipal water may have a strong chlorine taste or odor, which could lend off-flavors and aromas in your finished product. If you are using tap water to brew, it should be vigorously boiled or passed through a charcoal-type water filter before brewing. Bottled spring water is more free of chemical contamination than tap water and is soft to medium in hardness. Distilled water is the softest water available but is more expensive than bottled spring water. Mineral water should not be used unless the mineral content is known and acceptable for the style of beer being brewed.

As implied above, water can be considered either "hard" or "soft." Water with a high mineral content is considered "hard," whereas water with a low mineral content is considered "soft." Water hardness is measured in two ways: temporary hardness and permanent hardness. The total hardness of water is the combined effect of these two measurements.

"Temporary hardness" or "bicarbonate hardness" is a measure of the water's bicarbonate ions. Bicarbonate hardness is considered temporary because bicarbonate ions easily precipitate during boiling and are thereby removed. Too many bicarbonate ions increase the alkalinity (raises the pH) of the water and impart harsh, bitter flavors to the beer. High alkalinity of the liquor also results in the inadequate conversion of the starches in the grains to fermentable sugars.

"Permanent hardness" is a measure of the water's magnesium and calcium ions. Too many calcium and/or magnesium ions increase the acidity (lower the pH) of the water. Some permanent hardness is desirable to brewers as enzyme conversion works best at a pH around 5.2 (slightly acidic).

Below is a list of the six main ions in water and their effect on beer:

1. Calcium - The most important mineral ion in brewing. Primary ion determining permanent hardness in beer. Helps lower pH in water to optimum levels for enzyme action and helps precipitate proteins during boiling and fermentation.

2. Bicarbonate - Determines the temporary or bicarbonate hardness of beer. The presence of bicarbonate is considered one of the most crucial factors in liquor. Counteracts the effect of calcium in the water. Too much results in poor extract yields from malted grain and creates a "soft" beer.

3. Sodium - Contributes body, mouthfeel and character. Too much creates a noticeable salty taste to the beer.

4. Chloride - Brings out malt sweetness. Contributes to mouthfeel and complexity in beer.

5. Sulfate - Main water element that effects hopping rates. Brings out a sharp, dry bitterness in beer if IBUs are too high.

6. Magnesium - Primarily a yeast nutrient. Should not be added artificially.

The following is a list of common water treatments and their effect on beer:

1. Burton Water Salts - A combination of gypsum, magnesium sulfate and sodium chloride. Used to replicate the mineral content of the water traditionally used in brewing classic British pale ales.

2. Gypsum - Increases calcium and sulfate ions. Used to lower pH levels. Not ideal for brewing lagers.

3. Table Salt - Increases sodium and chloride ions. Generally advised against adding.

4. Epsom Salts - Increases magnesium and sulfate ions. For permanent hardness to mimic Burton-on-Trent waters.

5. Calcium Carbonate - Increases temporary hardness and pH (increases alkalinity/lowers pH).

6. Calcium Chloride - Increases calcium and chloride ions.