All about the WATER!To prepare a good coffee really well, you need more than expensive coffee. You should use an exact recipe and weigh the coffee and water to the gram.
Your coffee is 98% (filter coffee)/90% (for espresso) water. You should therefore use good water. But what is good water?
With too much or too little minerals your brew will never be really good. So here's a tip on how to find the perfect water.
One secret to the perfect water should be revealed in advance: Never use distilled water!
How good is tap water for brewing coffee?
You can use tap water to make your coffee, but it's not ideal. All tap water contains many minerals and organics that may not taste great in your coffee.
The extraction of the coffee is a chemical reaction.
In order for this reaction to happen optimally, the water must contain minerals. With the right amount, your coffee will be optimally extracted: Your water should have a mineral content between 100 and 200 mg/ L.
To find out how good (or bad) your tap water is for making coffee, i.e. how high the mineral content is in your water, you can check, for example, "www.mineralienrechner.de/".
A water with a high mineral content that suits your brew is Volvic.