The Impact Of Water Quality On Coffee Taste And How To Optimise It

The Impact Of Water Quality On Coffee Taste And How To Optimise It


Water is an essential ingredient in brewing coffee, making up over 98% of your cup. The quality and composition of the water used can significantly impact the final taste of your brew. Factors like mineral content, pH level, and the presence of contaminants all play a role. In this article, we'll explore how water affects coffee flavor and share tips on optimizing your water for the best tasting cup.

The Role of Minerals in Water for Coffee

The mineral content of water, particularly magnesium and calcium, contributes to coffee extraction and flavor development. Water that is too soft (low in minerals) can lead to under-extracted, weak tasting coffee. On the flip side, overly hard water with excessive minerals can result in bitter, chalky flavors. Aim for a balanced mineral content of around 150 ppm for optimal extraction.

Mineral Ideal Range (mg/L) Impact on Coffee
Calcium 50-175 Enhances body and mouthfeel
Magnesium 10-50 Aids extraction, adds sweetness
Sodium 10-30 Can add salty taste at high levels
Bicarbonate 50-175 Buffers acidity, affects flavor clarity

Choosing the Right Water for Your Coffee Machine

The type of water you use in your coffee machine matters for both taste and equipment longevity. Hard water high in minerals can lead to limescale buildup, damaging your machine over time. Conversely, purified water devoid of minerals can be corrosive. Opt for filtered water or mix filtered and tap to achieve the right balance.

Optimizing pH Level for Coffee Extraction

The ideal pH range for brewing coffee is between 6.5 to 7.5. Water that is too acidic can lead to sour, acidic coffee while overly alkaline water produces a flat, dull brew. If your water falls outside this range, consider using pH strips to test and adjust it with additives like baking soda (to raise pH) or citric acid (to lower it).

Removing Impurities with Water Filters

Contaminants like chlorine, pesticides, and heavy metals in water can impart off-flavors to your coffee. Using a water filter is an effective way to remove these impurities for a cleaner tasting cup. Carbon filters are a popular choice that can be used in pitchers, faucet attachments, or under-sink systems.

The Benefits of Fresh, Cold Water for Brewing

Always use fresh, cold water when brewing coffee for the best taste. Avoid using hot tap water, as it can pick up contaminants from your pipes. Fresh, cold water is also more oxygenated which aids in extraction. If you have old, stale water sitting in your kettle, discard it and refill with fresh water before brewing.

Experimenting with Different Water Types

The unique composition of water in different areas can highlight various aspects of the same coffee beans. Experiment with bottled spring water from different regions to taste how the mineral content affects flavor profile and nuances. You may find certain water pairs better with particular coffee origins or roasts.

Third Wave Water for Optimal Coffee Chemistry

For the serious home barista, Third Wave Water offers mineral capsules designed to create ideal water composition for coffee brewing. Simply add a capsule to distilled or reverse osmosis water for balanced water chemistry ready for brewing. This takes the guesswork out of adjusting your water's mineral content and pH.

The Environmental Impact of Bottled Water for Coffee

While bottled spring water can provide a taste upgrade for your coffee, keep in mind the environmental impact of single-use plastic bottles. Where possible, opt for filtered tap water, larger reusable jugs of spring water, or install an under-sink filtration system to minimize plastic waste while still enjoying great tasting coffee.


Optimizing your water quality is a simple way to dramatically improve the taste of your coffee at home. By understanding the role of minerals, pH, and contaminants, you can tailor your water to highlight the best qualities of your coffee beans. Experiment with filtration methods and mineral composition to discover the perfect water recipe for your daily brew. Great coffee starts with great water!

Back to blog