THE OPTIMAL WATER FOR COFFEE
The Crucial Role of Water in Coffee Brewing
In the pursuit of the perfect cup, coffee enthusiasts often prioritize gear, good beans, and brewing techniques. All for very good reasons. However, a subtle but critical player often escapes the spotlight – water. Beyond its apparent simplicity, water is the primary extractor, the solvent responsible for unlocking aroma and flavor.
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Key points (If new to coffee water)
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More than 90 % of the brewed coffee is water. It might just be important...
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Water works as the solvent of coffee = Extraction!
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The minerals Calcium and Magnesium are important flavor extractors!
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You want approximately a pH-level of 7 with some buffer in your water to help sustain pH-level
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The Holy Trinity of Coffee Brewing
My humble opinion, in relation to a hypothetical and somewhat arbitrary ranking of variables, will always be formulated as follows:
THE QUALITY OF COFFEE, CLEAN EQUIPMENT AND THE QUALITY OF WATER
– and the quality and type of equipment will always come second! I would be remiss if I didn't emphasize the importance of the grinder in any setup, however, it is still a secondary priority.
General Guidelines
1. Purity
Use clean and filtered water to ensure that impurities and unwanted flavors are removed.
2. Minerals
Some minerals are essential for a good cup of coffee. Magnesium and calcium in particular contribute to the extraction of important flavor compounds. However, too many minerals can result in either flat or bitter flavors, so a balanced mineral content is important.
3. pH level
The pH level of water should ideally be around 7 (neutral). Water that is too acidic or alkaline is very negative for both taste and aroma.
4. Freshness
Always use fresh water. Water that has been left for too long can also appear flat and slightly acidic.
These are general guidelines and personal preferences play a major role in water chemistry. Experimenting with different water sources and compositions can help you find the perfect match for your taste buds and brewing methods.
Specifics
1. Hardness
Hardness is the concentration of minerals in the water, primarily calcium and magnesium. Relatively soft water with magnesium is often preferred for coffee brewing as it gives a better mouthfeel and helps bring out the acidity, sweetness and aroma of the coffee. In addition, water that is too hard can lead to limescale deposits in the coffee machine and negatively affect the taste.
Water that is too soft, RO water or distilled water often becomes acidic as the uncharged compounds in the water accept CO2, which dissolves and forms carbonic acid. This water creates a broad, undefinable acidity in the coffee, which essentially dilutes the coffee's natural acidic properties.
2. Total Dissolved Solids (TDS)
TDS refers to the total amount of dissolved solids in the water (it can be an ok indication of the hardness of the water). A certain level of TDS is necessary to extract flavor and aroma, since it is often an indication that calcium and magnesium are present. However, TDS does not help to express exactly how much hardness is present or whether the balance of the 2 desired minerals is optimal. To start with, you should aim for a TDS level between 50-120 ppm (parts per million).
3. Chlorine and chloramines
Chlorine and chloramines can be a common occurrence in tap water and can give coffee an undesirable taste. It is recommended to use water that has been dechlorinated (through filtration).
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4. Bicarbonate (buffer)
A buffer solution acts as a "protector" in the chemistry of the water. Buffer in water maintains the pH balance and prevents drastic changes. It consists of a weak acid and its conjugate base or a weak base and its conjugate acid. When things get too acidic or alkaline, the buffers step in to neutralize and maintain the pH. This also happens as we add coffee to water.
Keep in mind that these factors interact and that the "ideal" water can vary depending on roast level, coffee beans, brewing techniques, and your personal taste preferences. It's a bit of a scientific endeavor, but the results of the water experiments may be just the thing to finally crack the code and unfolds the coffee.
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