Chances are you've purchased loose tea or teabags after you enjoyed a brewed cup of it at your local tea shop. Did you ever find when you brought it home that it didn't taste the same? Maybe it even tasted bad. If you've had such an experience, your water may be the culprit.
In the West we might assume our tap water is fit to use for tea "as is" simply because it’s safe to drink. Maybe that's true in your town, but it's also quite possible your water isn't fit for making a good cup of tea.
We know that pH level, chemicals and minerals, freshness, and starting temperature are important to brewing tea (see Water—The Mother of Tea). You can easily control freshness and starting temperature; let's look at simple methods of water testing to evaluate and improve the pH level and chemical/mineral levels to make them better for tea.
To learn what kind of tap water you have in your house, you can contact your water supplier or do an Internet search of their website. Conducting an online search on mine, I learned that my water comes from the Spada Reservoir, located at the headwaters of the Sultan River. I also discovered that the water is comprised of rain and snow melt from the Cascade Mountains. The water quality report told me that the pH ranges from 7.6 to 9.2 and averages 8.2. So now I know that my tap water is alkaline because it’s greater than 7. (By the way, the report also told me a lot more than this. Check out your local water service—you’ll come away enlightened.)
If your water service doesn't provide this information, an easy way to do a subjective water test is to leave a container of fresh tap water to stand overnight. By the morning the chemicals will have either evaporated out or fallen to the bottom of the container. Gently remove some water from the top half and taste it to find out if you like it better than fresh from the tap.
There are many ways to measure pH. You can use a glass electrode, a pH meter, or the indicator method. You might have used the last of these in your high school chemistry class. Remember? You added a small amount of an indicator substance (usually a few drops of a liquid) to the solution you were testing. The resulting color told you the acidity or alkalinity of the substance.
If you have a pool or spa you might have used test strips to assess water quality. On these, a little block on the strip indicates the pH of the water so that you can adjust the chemicals properly. Although they're not as accurate as using other methods of water testing, they should be sufficient to test for tea drinking purposes.
If you like your tap water for drinking, you'll probably like it for tea. If you don't like it, then you might consider testing a few different sources such as filtered water and different kinds of bottled water.
Here's a simple test you can perform to help choose the best water for tea.
First, devise a simple rating system to help with your evaluations. In these water tests, your nose and tastebuds are the judges, so you might want to assign scores based on smells and tastes, ranging from bad to neutral to good. (For example, I use a score of -1 for bad, 0 for neutral, and +1 for good.)
For the first part of the test, you'll evaluate plain water from a variety of sources. Bring each water to a boil in the same manner, then let them cool. Use your rating system to evaluate each of the waters according to taste, smell, and any other discernible qualities you detect.
Next, brew a cup of tea with each of the waters that tested well in the previous step. Use fresh water, and be sure to keep all other variables the same (i.e., amount of tea used, steeping time, etc.) except for the type of water. Evaluate the brewed teas in a manner similar to that used in the initial tasting. Make notes—do you notice any differences among the different brews? If you kept all other factors the same, then the type of water used made the difference.
Not only will this experiment help you decide which is the best water to use for your tea, it will also give you an idea of how different water interacts with tea. It's said by some that a delicate tea requires purer water than a robust, black tea. Doing water testing like this can help you make your own decision.
If you've found that your water quality is less than optimal, don't be distressed. Filtering your water is an easy and fairly inexpensive way to get better water for tea.
Filtering water results in softening and purifying the water. In Asia, bamboo charcoal is often used for this purpose. Bamboo charcoal both filters impurities from the water and returns some minerals. While I haven't used this method, filters are available online.
In the U.S. activated charcoal water filters are quite readily available. These can be installed under the sink, on the tap, for the entire house, or used in filtering pitchers on the countertop. The activated charcoal in these filters traps organic compounds such as chlorine and calcium. They do not filter out minerals or salts.
If you decide filtered water works best for you, it's worthwhile to consult a local water supplier about replacement filters. They'll be familiar with local water issues, and they can likely recommend the most appropriate filter that will give you the best water.
Using bottled water is another option. Since this is more expensive than installing a filter, it's worthwhile to try the subjective tests indicated above with one or more bottled samples to determine your favorite.
Bottled water comes in many varieties. When making your selection, your best bet is to use one with little or no mineral content. The pH level should be indicated on the label—look for a number near 7 (neutral).
There are two types of water you should always avoid for brewing tea: distilled water and hot-spring water. Both have lost all their natural elements and are invariably worse than using tap water. In the case of distilled water, it has been de-oxygenated and will result in a flat-tasting tea.