an intuitive guide to coffee solubles, extraction and tds - 4

strength is the ratio of solubles to water in your cup

until this point everything has been about extraction, the balance of good and bad solubles that are released from each cell. now lets look at strength, also known as total dissolved solids ( tds ).

tds can be simply defined as the ratio of solubles to water in a cup. this is largely a matter of personal preference but it is generally considered that 1.15% to 1.35% is an optimal ratio.

this means that for every 1 soluble we have 99 parts water.

the solubles released during extraction determine the flavor and tds determines the intensity of those flavors. this is similar to music if you think of solubles as the music itself and tds is how loud the volume is set. 

increasing tds will produce a stronger flavor but turning it up too high may cause some flavors to over power others completely.

extraction and tds are the two ratios that define coffee brewing. hopefully this story has helped develop an intuitive understanding of what is happening when coffee grounds steep in water and why small changes in the ratios can lead to big differences in flavor. 


you now have the tools to dial in your brewing recipe and get the best flavor out of our coffee beans. the only thing left to do is to start experimenting and free some solubles !