Parts Per Million (PPM)
Parts Per Million (PPM) is a unit of measurement for the concentration of minerals and impurities in water, which helps determine whether the water is suitable for brewing coffee. According to SCA, the optimal mineral content for specialty coffee brewing ranges from 75 to 250 PPM, with 150 PPM being the ideal benchmark.
If the PPM is too low, the water lacks sufficient minerals to properly extract flavors from the coffee, resulting in a weak and flat taste. On the other hand, if the PPM is too high, excessive minerals in the water can extract unwanted compounds, leading to bitterness and the loss of complex acidity.
Magnesium and calcium are the two key minerals in water used for specialty coffee brewing. While low-PPM water with a high magnesium content is often preferred, as it helps enhance and preserve the coffee’s vibrant acidity.
