98% of coffee is water! The type of water you brew coffee with will significantly affect the taste of coffee. This post we get to the details about water for coffee and how to DIY water, let's get started!
Types of water
There are couple types of water that you can easily find anywhere in Malaysia.
Distilled & reverse osmosis water have zero minerals content, ie 0 ppm. But for coffee, you need some minerals to extract the flavours. Coffee tastes flat and bland if you brew with RO/distilled water.
Mineral/spring water usually have high ppm and very often a little alkaline because of high calcium content.
Calcium neutralise acidity in coffee. This makes coffee taste kinda heavy and easily over extracted (sharp bitterness). Also, it builds up limescale in your kettle very quickly. So... not recommended.
That said, alkaline water is not good for coffee brewing too.
Spring water for coffee?
Thankfully, our tap water is pretty soft and clean (with less than 100 ppm, depending on location). Just install a simple water filter and you are good to go!
Yes, the best water for coffee is the one you have at home!
However, if you are staying in old building with old water pipes. You may notice some metal taste even with filter water. For that, you might wanna consider ‘DIY water’ for coffee.
DIY water 💧
If you realised that your tap water tastes kinda weird for coffee (eg. metallic etc) and you don’t want to spend on water filter. You can try out DIY your water for coffee!
Three things that you need to get, baking soda sodium bicarbonate (NOT baking powder), Epsom salt magnesium sulfate and distilled/RO water. They can be easily found in supermarket and pretty cheap too!
Yes, distilled water is bad for coffee. But we are adding minerals to water that makes coffee taste great!
Ingredients for DIY water.
Add 8.6g of baking soda and 25g of Epsom salt into a 500ml distilled water. Shake well until all dissolve. This is your mineral concentrate. (Credits to Barista Hustle)
We like to use the 9.5l distilled water container, so you don’t have to repeat the same too quick too often (especially if you drink 4-5 cups a day)
Then pour 15ml of mineral concentrate to the 9.5l distilled water (about 3.3ml per litre), and your DIY water is ready for brewing!
The more concentrate you put in distilled water, the harder the water (higher mineral content and ppm), the easier for you to extract coffee.
Let’s say if you only brew with light roast coffee, you may want to use a little more concentrate (4ml per litre).
For us, we brew any coffees that come to our hand and brewing all kinds of roast level. We don’t want to have too much minerals in water that easily over extract darker roast coffees.
Lastly, if you really want to learn how each minerals affect coffee taste, try putting individual mineral into distilled water and brew it. PS: they may taste pretty bad =X
Btw, DIY water recipe has no calcium in it, hence it does not build any limescale in your water kettle. Your water kettle will look just like new even after months of usage =)
What's the best temperature for coffee brewing?
The Best Brewing Temperature
After brewing and testing with lots of coffees, we concluded that the brewing temperature correlate to roast level of coffee beans.
Lighter roast coffee tastes better (in terms of extraction, body and sweetness) on higher brewing temperature, whereas darker roast tastes better on lower brewing temperature.
Here’s our recommended brewing temperature,
Light roast coffee, try 95-98ºC.
Medium roast, try 93-95ºC.
Dark roast, try 85-90ºC.
If you are brewing high altitude coffee (2000masl above) light roast Panama Gesha, try boiling water. You get a real sweet and flavourful cup!
Boiling water for coffee? Sure!
We strongly recommend NOT to adjust brewing temperature as a parameter.
It requires a certain amount of energy (heat) to extract all the flavours in light roast coffee. Hence a lower brewing temperature often result in unpleasant sourness and hollowness from under-extraction, despite brewing with a finer grind.
The opposite for dark roast coffee, high brewing temperature easily result to over extraction that result to super bitter and harsh aftertaste.
Good ingredients make good food, same to coffee. With the right water and freshly roasted coffee, you'll get to enjoy delicious coffee at all time!
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