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Brewing great tasting coffee is a science. You spend time researching the perfect coffee maker, you buy well-roasted coffee beans, and you’re constantly trying to tweak and improve your coffee brewing techniques. However, there’s a vital element that’s often overlooked by many homebrewers and even professional baristas – I’m talking about water quality!
When you notice that something just isn’t right with your coffee the finger is often pointed in the direction of the coffee beans as being the culprit for brewing a flat or bitter cup and to be honest that’s a good place to start. But, there’s another component of your brew that makes up roughly 98%, yep, you guessed it water. The type of water you use in your coffee can adversely affect the taste of your final brew, and even regular tap water can alter the taste of your coffee in unpleasant ways.
Not all water is equal, and it’s actually shocking how much difference using the best water for coffee makes. But isn’t water just water? Yes and no. In most cases, water chemistry isn’t going to be a big deal for home coffee brewers and if your water tastes good for drinking it will most probably taste good for coffee, and to an extent, this certainly holds true.
Tap water is the common culprit for adverse tasting coffee, and the mineral content and PH level of the water can have drastic effects on the finished brew. Water quality can also affect your coffee brewing equipment and depending on the area you live you might have already seen the negative impact the local water has had on your coffee maker.
If you think that you may have problems with your water quality here are a few basic water brewing factors that can affect the taste of your coffee.
Staleness and Quality
It goes without saying that the water you use for your coffee should be fresh, clean, and obviously don’t ever use water that you wouldn’t want to drink by itself. The cold water faucet is going to be a better option versus the hot water faucet, and it’s going to taste fresher, so if you thought you could give your whistling tea kettle a jump start by using warm water don’t do it.
Also if you have some old water in your kettle leftover from the last time you used it throw it away. Old, boiled water that’s been allowed to cool will have lost almost all of its freshness due to loss of oxygen, and it can also change the way the coffee and water will react together.
If you’re unsure about your regular tap water, it’s best to buy a third-party filter. A simple, affordable water filter will vastly improve the quality of your water for brewing coffee.
Filter Your Tap Water
A good water filter is probably going to be your first port of call if you’re having an issue with the quality of your tap water. The SCAA water brewing guidelines (1) clearly mention that the best water for coffee should be odor-free, clean, and with no chlorine – if you invest in a water filter you can tick all of these boxes.
Portable pitcher water filters that can fit inside of your fridge door like the Brita are a great option, and they utilize activated carbon to remove odors, chlorine, and other water impurities. For under $30 you can’t go wrong with this type of filter especially if you’re brewing coffee just for one.
Another popular and cheap option to filter your water for coffee is to use a faucet-mounted type of filter – like this. This kind of filter attaches to your kitchen faucet and filters your water when the tap is on; a great option for those of you that want to set and forget!
Unfortunately, the quality of the water where I live isn’t the best, so after constantly spending money on bottled water for my coffee brewing needs I finally dug deep in my pocket and invested in a Berkey water filtration system. This setup isn’t the cheapest by any means, but the money I’ve saved by not buying bottled water will make the Berkey pay for itself.
Water Hardness (Soft or Hard Water?)
The hardness of your water can also adversely affect the taste of your coffee. Water hardness refers to how much magnesium or calcium you have in your water. I find that having these two minerals (especially magnesium) in your water actually improves the taste of your coffee.
But others disagree, stating that these minerals act as magnets that attract the flavor compounds to then form solids which in turn decreases the amount of flavor in your coffee. It’s a tricky one, and there’s no clear answer, but as far as I’m concerned replacing these minerals and just leaving sodium produces a coffee that’s is flat and has no life.
A downside of having hard water is the limescale which due to all of the minerals which build up over time on your coffee brewing equipment; this is especially problematic with espresso machines.
To help combat the hardness problem many people opt to use a water softener, but this can mean trouble for the flavor of your coffee. These water softeners can help in reducing the hardness of your water, but they also increase the amounts of salinity which unfortunately can alter the taste of your coffee.
Because everyone’s taste perception is different, I recommend that you do a comparison test between your soft and hard water and then decide which one you like better.
If you want more information on water hardness and its effects on coffee I recommend you have a read of Jim Schulman’s Insanely Long Water PDF (2). This PDF contains a vast amount of information on this subject, and although mainly focused on espresso brewing you’ll find some gems of information that’s valuable for all types of brewing.
Using Reverse Osmosis Water for Coffee
Reverse Osmosis is another popular way to filter your drinking water. However, this process removes everything, and that’s not ideal for brewing great-tasting coffee. With the missing magnesium and calcium that helps to elevate your coffee the Reverse Osmosis water will brew a coffee that’s flat and dull.
But it’s not all doom and gloom for Reverse Osmosis you can find specialized blending machines that will allow you to customize the number of solids in the water and will put back the lost essential minerals. This now makes Reverse Osmosis a great option for the best water for brewing coffee and with the ability to tweak your water to your liking you’re guaranteed to have clean filtered water with just the right amount of minerals to elevate your final brew.
If you want to get technical with your water, it’s possible to blend the water yourself. However, I think this is pushing the realms of water filtration to the limits and is a hell of a lot of work for a good tasting cup of coffee. If you do decide to take this route, the SCAA recommends 150 mg/L total dissolved solids; but trust me its a lot of messing around.
Bottled Water for Coffee Okay?
If you don’t have deep pockets but still want to brew a great-tasting cup of coffee there’s nothing wrong with shop-bought bottled water; however, using bottled water is not a simple cut and dry issue either.
Every brand of bottled water contains different minerals and varying PH levels so choosing the best water for coffee can be a challenge. But help is at hand, to limit your search try to look for water labeled as spring water; Volvic or Crystal Geyser are going to be some of the best water for coffee from my experience.
References
(1) Specialty Coffee Association of America (SCAA). https://www.scaa.org/PDF/resources/water-standards.pdf
(2) Jim Schulman’s Insanely Long Water FAQ. http://users.rcn.com/erics/Water%20Quality/Water%20FAQ.pdf