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.
For example, if we have a 100g cup of filter coffee, with a TDS of 1.5%, there are 1.5g of coffee solids dissolved in 98.5g of water.
TDS is a measurement of strength. Sensorially, TDS is tied to viscosity and intensity. The stronger a coffee, the heavier and more intense it becomes. The weaker a coffee, the lighter and less intense it becomes.
It’s important to note the difference between strength and intensity. For the purpose of this course, strength (strong, weak) will always be in reference to the % TDS of a coffee, while intensity (intense, mild) will always refer to the sensory impressions of perceived potency or magnitude of a flavour. A weak coffee can have an intense blueberry flavour, while a strong coffee can have a mild blueberry flavour.
It’s also important to note these numbers need connections to subjective, experiential descriptors and trends.