Categories
brewing coffee

Facts about coffee

Ideal coffee water is fresh and pure in taste and has no discernible odors. It should be mineral-rich, yet have a balanced mineral content. A total hardness of 7–12° EH, a carbonate hardness of 3–4° EH and a pH value of 6.5–7.5 are ideal. Only then can coffee develop its full aroma.

Source: Deutscher Kaffeeverband

Read more about the meaning of EH or Eh, as chemical literature calls it, here.

What does this mean for anyone on a small island making coffee?

  • Don’t use tap water!
  • Don’t use water that has been desalinated!
  • Don’t use Reverse Osmosis (RO) water!
  • Don’t use just any mineral water but pay attention to pH and “dissolved minerals” per liter

If you do get RO water, get some tablets from Third Wave Water and you are fine!
Update: Chemists at MIT and 2 UK baristas have made a deep dive on this subject and analysed why soft water is particularly bad for making coffee.

By Christian

Coffee has been my life line for decades, the smell would wake me up whenever my parents would brew a pot. Working part-time in Food&Beverage since 2006, I've unknowingly narrowed my field of flavors and odors from chef in the kitchen to sommelier at the dining table to barista with coffee since 2016. SCA Certified since 2017. With a background in chemistry, understanding the brew methods was very easy for me. Combined with an insatiable curiosity for knowledge, I strive to learn even more about the world of coffee. Currently building up experience to participate in the Dutch Brewers Cup 2022 and perhaps WBrC 2025!