Dose means the weight of dry ground coffee.

When changing the Ratios across the 120-point Roast Spectrum, it is really useful also to change the Espresso Dose.

For example, with a very light roast with a 1:4 ratio, a 14g dose produces a just manageable 56g yield of espresso. If you used a larger 20g dose, you would need a massive 80g, which exceeds the brew chamber of devices such as the Flair 58. It is much easier to achieve high ratios when you reduce the dose.

With a very dark roast with a 1:1 ratio, increasing the dose to 25g keeps the yield up at 25g.

As the density indicates, using the right dose for the Roast Level helps get the extraction right.