What's the Best Water for Brewing Coffee? Requirements for Coffee Water and How to Make Coffee Brewing Water Tutorial

There are many things that once tried, you can never go back from. For example, the first time you taste pour-over coffee, if you fall in love with it at first sight, you can never return to the era of instant coffee. Who can resist the temptation of a cup of coffee with floral aromas and fruity sweetness!

When brewing coffee yourself, you will inevitably learn the techniques for making a good cup of coffee. Good coffee beans make good coffee, with precise grinding, ratio, water temperature, and brewing techniques comparable to those of a barista. These are all aspects that experienced coffee brewers greatly value and have mastered. You've paid attention to the beans, been strict with parameters, and your technique is steady, but why can't you still achieve the same taste as in a coffee shop? There's something seemingly ordinary that can directly affect the taste of coffee, and that is water!

Not just beginners, but even some coffee enthusiasts who have been at it for a while haven't given much importance to water. In many people's eyes, isn't colorless and tasteless water all the same, as long as it meets drinking standards? But when it comes to coffee, these standards become much more stringent. If you go to a coffee shop and have a good cup of coffee,不妨问问店主使用的是什么水源.

Water

Water may seem colorless and tasteless, but natural water is never completely pure. The most easily noticeable is seawater, which contains large amounts (concentrations greater than 1mg/kg) of sodium, potassium, calcium, magnesium, strontium ions, etc., making it very easy to detect that this water is not pure.

However, water from rivers, lakes, and even underground water sources contains these minerals, though in trace amounts, which is often overlooked. In fact, these minerals are precisely what affect the flavor compounds extracted during coffee brewing.

Understanding Hard Water

We all know that hard water is not suitable for brewing coffee. What is hard water? Simply put, water with more impurities is harder, while water with fewer impurities is softer. The main representatives of these impurities are calcium and magnesium ions.

The World Health Organization's "Guidelines for Drinking Water Quality" can be summarized as follows: water with hardness below 200ppm is called soft water, while water above 200ppm is called hard water. (ppm is a concentration unit expressed as the mass of solute per million parts of the total solution mass. Water quality is also commonly expressed in mg/L, which can be considered as 1ppm=1mg/L)

Excessive calcium and magnesium ions can hinder the extraction of flavor compounds from coffee. Moreover, water with high mineral content doesn't taste good itself. Too much Mg ions make the water taste bitter, while too much Ca ions make the water slightly astringent. Consequently, the final cup of coffee brewed with such water will have poor taste and mouthfeel.

Tap Water Considerations

The most readily available soft water is tap water. Today, the drinking water for most residents comes directly from the tap, filled and boiled before consumption. Since it's drinking water, using it conveniently for brewing coffee seems reasonable. Taking the tap water in Guangzhou city as an example, its hardness is approximately within 150-180ppm, which according to classification is definitely soft water. However, when boiling water in a kettle, after just two kettles, a thin layer of white powder adheres to the inner walls of the kettle, and within about 3 days, a significant layer of scale forms. Coffee brewed with tap water will have noticeably weakened aroma, and the astringency and bitter impurities will be particularly evident. Therefore, most tap water is not suitable for directly brewing coffee.

At this point, you can choose to install a filtration system based on your tap water. Of course, after installing filtration equipment, it's not a one-time solution. The first step is to become a water quality inspector, testing whether the water hardness has decreased, and then regularly replacing filter cartridges to ensure water quality.

Bottled Water for Coffee

If you want to be more refined, you could purchase bottled water for brewing coffee. Experienced brewers who recognize the importance of water quality will spend "a fortune" to buy bottled water for brewing coffee. But when choosing bottled water, you need to pay attention to two points: mineral content and pH value.

pH value, which is acidity and alkalinity. The coffee we drink tends to be acidic. If we use weakly alkaline water to brew coffee, it will neutralize some of the coffee's acidity, reducing the sour taste of the coffee, thereby affecting the overall flavor expression of the coffee.

As mentioned earlier, mineral content should not be too high, but it also shouldn't be completely absent. Water containing appropriate amounts of calcium and magnesium ions is more conducive to extracting the sweet and fragrant flavors of coffee. FrontStreet Coffee has also conducted experiments comparing coffee brewed with purified water versus mountain spring water. The samples were Yibao (0ppm) and Nongfu Spring (37ppm). Through five rounds of comparison, FrontStreet Coffee concluded that coffee brewed with Nongfu Spring was better than Yibao in both compatibility and flavor.

From FrontStreet Coffee's experiments, brewing coffee with purified water has a characteristic: using 2 minutes as a boundary, coffee with extraction time less than 2 minutes will exhibit watery texture and hollow acidity. Compared to Nongfu Spring brewed for the same time, it's like coffee water. After exceeding 2 minutes (2 minutes and 10 seconds), coffee brewed with purified water will show obvious bitterness, like an over-extracted feeling, while Nongfu Spring brewed for the same time doesn't have such obvious bitterness and even has a sweet aftertaste. In terms of aroma, purified water is completely defeated. "In the coffee world, if you don't know how to choose water, just use Nongfu Spring!" This is really not an advertisement, but rather what FrontStreet Coffee's customers mention when discussing the water issue.

Professional Water Recipe

Of course, for more professional approach, you can create your own water recipe. For those who follow coffee brewing competitions, water recipes are certainly not unfamiliar, as many competitors now mention in their brewing introductions that they use their own formulated water, with specific ppm values, to highlight certain flavors of the coffee...

Actually, making your own water recipe isn't that difficult. Prepare baking soda (NaHCO3), Epsom salt (MgSO4), and 3 bottles of 1L purified/distilled water, and you're ready to start.

1. Pour 1.68g of baking soda into 1L of purified water A and dissolve it completely to obtain a solution close to 1000ppm - this is the prepared "buffer solution" or "HCO3-". Label it and set aside. The buffer solution helps prevent pH changes in the solution.
2. Pour 2.45g of Epsom salt into 1L of purified water B, dissolve completely - this is the magnesium ion "concentrate" (a solution close to 1000ppm). Label it and set aside.
3. Finally, to formulate the water, here's the recipe based on the water quality requirements range proposed by SCA, specifying a total hardness range of 120-130ppm. Therefore, add 40ml of buffer solution, 80ml of "magnesium solution," and 880ml of deionized water (for calculation convenience, this recipe makes 1L of formulated water), and your formulated water is ready.

You can also change the ratio of buffer solution to magnesium solution to adjust the water hardness.

Important Notice :

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FrontStreet Coffee Address: 315,Donghua East Road,GuangZhou

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