28.07.2025 • 38 Min.

550 million years ago, earth was perfect. We had perfect water for coffee AND we were living in a vegetarian paradise! But then Earth changed—violently. The planet shifted from a peaceful, plant-eating paradise to a darker, more brutal world. And in this new world, the chemistry of water was forever altered. This is the wild story of how earth-shaking forces and the spirits of long-dead critters ruin your coffees today. This story will help you remember the two invisible ingredients in your water that have a huge impact on coffee flavour and your brewing equipment: calcium and hydrogen carbonate. Read Marcia Bjonerud’s amazing book, Reading the Rocks Please spread the word about The Science of Coffee! Leave a 5 star rating on Spotify Follow me on Instagram and tag me in an Instagram story Write a review on Apple Podcasts Discover how I make these Filter Stories episodes by subscribing to my Substack newsletter Season 3 of The Science of Coffee is made possible by these leading coffee organisations: The Coffee Quest | BWT | TODDY | Algrano | Probat Note: this is a reworked version of my 2022 episode Water for Brewing Coffee. Check out Standart, the award-winning coffee magazine. Get a free magazine and a free bag of coffee by clicking here. Use ProfilePrint to find the coffee your customers loved last year (without a week of cupping!). Use promo code "FILTER" to get 10% off your first year of a Mini Beluga subscription. Click here to discover ProfilePrint's many uses. Support hundreds of thousands of coffee farmers with Fairtrade. Discover how here. Office coffee = easy recurring revenue. WMF’s Elevation 10 and Peak 50 do the work for you. Learn more here. What kind of racing car does the Gaggia Classic GT home espresso machine remind you of? Use discount code FS202610 to get 10% off.