As a brewer, the total alkalinity of brewing water is an important factor to consider in order to achieve the desired flavor and character in your beer. Total alkalinity refers to the amount of alkaline substances present in the water, such as bicarbonates and carbonates. These substances can affect the pH level of the brewing water and ultimately impact the taste and quality of the beer.
Ideally, you would want the total alkalinity of your brewing water to be less than 100 parts per million (ppm). A total alkalinity below 50 ppm is even more preferable, but it can be quite challenging to achieve such low levels in practice. In reality, you will often encounter total alkalinity numbers ranging between 50 and 150 ppm.
The reason for aiming for lower total alkalinity levels is to have better control over the pH of the brewing water. When the total alkalinity is high, it can lead to a higher pH, which in turn affects the enzymatic activity during mashing. This can result in poor conversion of starches to fermentable sugars and ultimately impact the flavor and body of the beer.
By keeping the total alkalinity within the desired range, you can ensure that the pH of the brewing water remains within the optimal range for enzymatic activity during mashing. This allows for better starch conversion and extraction of desirable flavors from the malt.
There are a few ways to adjust the total alkalinity of your brewing water if it falls outside the desired range. One common method is to dilute the water with distilled or RO (reverse osmosis) water, which has a lower alkalinity. This can help bring down the total alkalinity to a more suitable level.
Another approach is to use brewing salts or acids to adjust the pH and alkalinity. For example, adding calcium chloride or gypsum can help increase the total alkalinity, while adding lactic acid or phosphoric acid can lower it. It is important to note that these adjustments should be made with caution and in accordance with water chemistry calculations to avoid overcompensating or introducing off-flavors.
In my personal experience as a brewer, I have found that paying attention to the total alkalinity of the brewing water can greatly impact the final beer quality. By monitoring and adjusting the total alkalinity, I have been able to achieve better control over the mashing process and ultimately produce beers with more balanced flavors and improved mouthfeel.
While there is no strict threshold for the total alkalinity of brewing water, aiming for values below 100 ppm and preferably below 50 ppm can help ensure optimal pH levels during mashing and produce high-quality beers.