Choose a starting recipe and record the coffee dose, grind, beverage weight and brewing time. Taste the result, then change one variable and compare the next cup.
A bitter or sour note alone does not identify a single cause. Work through the recipe and equipment setup rather than applying a fixed temperature or time rule to every coffee.
Before changing products, use the
coffee beans versus espresso beans guide to decide what to compare. Keep the exact coffee reference with your recipe and tasting notes.