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Brew Control Chart

merrymacaroon.com
Plan
Measure

Measure Your Brew

TDS (%)
Extr (%)
Coffee Dose (g)
Brew Water (g)
LRR
BevWt (g)
Slurry TDS (%)

Plan Your Brew

TDS (%)
Extr (%)
Coffee Dose (g)
Brew Water (g)
LRR
BevWt (g)

Background

Plan mode

When planning a brew recipe, we usually think about the strength of the coffee and the flavors extracted from the coffee grounds. In the Brew Control Chart, TDS (Total Dissolved Solids) is a measure of the strength of coffee - the higher the TDS, the stronger the coffee. The Extraction indicates how much of the coffee grounds have been "drawn out" by the brew water - under-extracted coffee may taste more sour while over-extracted coffee may taste more bitter.

Design your brew recipes by setting your desired TDS, extraction-level and coffee dose, and let the app calculate the required amount of brew water to use. This app uses the equations described by Jonathan Gagné on his wonderful website coffeeadastra.com

As a start, try choosing a brew point (indicated by the green circle) inside the green box. You can tap on the Brew Control Chart to quickly set the brew point. The green box on the chart shows a general opinion of what is good tasting coffee. Choosing a point in the middle of the box gives more margin for error when brewing.

The red line shows the brew ratio (brew water / coffee dose) so you can easily describe your brew recipe.

Measure mode

If you have access to a refractometer (which measures TDS), you can compare your actual brew (indicated by the blue circle) with your plan. The weight of your beverage is estimated from the brew water. If you can measure the actual beverage weight, the extraction calculation will be more accurate.

For percolation brew methods (e.g. V60), the TDS of the slurry left after the brew is usually assumed to be 0. This is the default value used in our calculations (to be more consistent when comparing your extraction numbers with others). For an even more accuate extraction calculation, you can catch the last few drops of your brew in another container to take a separate (non-zero) Slurry TDS measurement.