Is Lower TDS Better for Coffee Water? What Are the Water Quality Requirements for Brewing Coffee in ppm?

FrontStreet Coffee wrote in a previous article that to achieve freedom in brewing coffee at home, you need to prepare a budget of over a thousand yuan. A good set of coffee equipment can make your efforts twice as effective, while the quality of coffee beans determines the upper and lower limits of coffee flavor. For beginners, water quality is often an overlooked issue.

Many beginners, after preparing a set of brewing equipment and coffee beans, begin their enjoyable brewing journey. As for water, they typically use tap water, or for those more particular, water filtered through a household filter. The resulting coffee often has an indescribable quality, frequently showing blurred flavors and heavy impurities. Then they attribute it to brewing technique problems, falling into a situation of "overthinking."

The Importance of Water Quality

Water quality is precisely a crucial factor affecting coffee flavor! Therefore, FrontStreet Coffee believes that to brew delicious coffee, understanding water knowledge is essential.

Although water appears colorless and odorless, and even tastes normal, using unsuitable water for coffee brewing results in unpleasant taste.

The factor affecting water quality is the amount of trace minerals contained in water. Generally expressed as TDS (Total Dissolved Solids), appropriate amounts of calcium and magnesium ions help with coffee extraction. However, excessive calcium and magnesium ions hinder the extraction of coffee flavor compounds. Moreover, water with high mineral content itself tastes unpleasant—too much magnesium makes water taste bitter, while excessive calcium gives water a slightly astringent taste. Consequently, the final brewed coffee will have poor taste and texture.

Therefore, tap water generally has high calcium ion content, as evidenced by the layer of white scale that accumulates in water kettles. Coffee brewed with such water tends to have an astringent taste.

"Note: TDS can only detect the content of dissolved solids and cannot specifically distinguish between magnesium, calcium, and other trace elements."

However, pure water without minerals is also unsuitable for brewing coffee. As mentioned earlier, appropriate amounts of calcium and magnesium ions help extract flavor compounds from coffee. Coffee brewed with very "clean" pure water will exhibit a hollow feeling, with weak aroma and aftertaste.

Just as the water we encounter daily contains not only calcium and magnesium trace minerals but also other minerals that affect coffee extraction, we often see top-level coffee brewing competitions where contestants even prepare their own water to better extract the good flavors from coffee.

Practical Water Recommendations

Such tedious water preparation is not something we would specifically do in daily life. For daily coffee brewing water, FrontStreet Coffee recommends using filtered water or bottled water.

In "Water for Coffee," the SCAA provides a TDS standard for water between 75-250ppm. However, based on actual performance, TDS values below 100ppm tend to extract better flavors. If you're using a water filtration system, you might want to test your water's TDS.

If you want to verify whether water quality issues are affecting your coffee's flavor, you can purchase commercially available bottled water for comparison. Regarding bottled water selection, judge by ingredient lists rather than price. Based on bottled water suitability and availability, FrontStreet Coffee recommends purchasing Nongfu Spring for comparison. (The excellent flavor performance of coffee produced by FrontStreet Coffee is partly attributed to Nongfu Spring.)

Important Notice :

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FrontStreet Coffee Address: 315,Donghua East Road,GuangZhou

Tel:020 38364473