Intro to TDS
The extracted mass in a beverage is referred to as the Total Dissolved Solids (TDS). It is usually expressed as a percentage of the total fluid mass. For example, an espresso is somewhere between 7–12% TDS, whereas a filter or drip coffee might be around 1.4% TDS.
Once we know the % TDS and the weight of a coffee beverage, we can figure out how much coffee flavour there is dissolved in the water.