>Here we show that cyclic voltammetry can be used without any additional sample preparation to directly measure the strength of a coffee beverage and, separately, how dark the coffee has been roasted; these two properties are implicated in the sensory profile of the beverage.

those two properties do not even touch on the quality of the beans, nor how those flavors are developed and maintained through roasting. measuring the darkness of roast does not tell you how dark the coffee should have been roasted for optimum flavor profile.

I'm not aware that it can be done analytically, it requires trained tastebuds, and in my experience, tastebuds trained on many coffees over time (a sort of 10,000 hours type idea, probably needs neuroplasticity); most roasters have a sort of narrow "tunnel vision" based around their own coffees which they taste relentlessly.

to actually taste delicious coffee it needs to cool down quite a bit, below 130F 55C which is not very hot. I understand the pleasure of a hot cup of coffee, but that pleasure is not flavor pleasure.