If you’ve ever made a cup of coffee and wondered “Why is this different from the last time I made it?” I’d be willing to bet that temperature is one of the main culprits.
The act of brewing coffee is essentially causing water to be in contact with the coffee for a certain amount of time. For pour-over brewing, the timing and technique of pouring the water takes considerable skill.
We did an experiment to quantify the effect of Ratio on brewed coffee. The results show a nearly perfect direct, linear relationship between Ratio to TDS. As the ratio widened by 1, the TDS measurement went down by one tenth of a percent.