Different coffee varieties can produce very different flavour profiles. A different flavour profile points to differences in the chemical mix inside the cup.
Are there any studies that quantify these differences?
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Additional information on the chemistry of coffee taste. This is produced by what we know as the Maillard Reaction - the Maillard Reaction (MRx). Discovered by a French chemist in 1910 the MRx is what is largely responsible for transforming the mere handful of compounds found in green coffee (unroasted) to the complex aromatic beverage that it is today. As temperatures reach 150°C (302°F) the MRx causes free proteins to combine with sugars to form aromatic compounds such as furans which impart sweet, caramel like notes to the coffee. :
More on this chemical reaction here: https://www.coffeechemistry.com/library/coffee-science-publications/unlocking-coffee-s-chemical-composition-part-2
Remember. Coffee differs from region to region - water, soil, temperature, altitude, sunlight, humidity, etc. Many, many factors go into how coffee gets its distinct flavor and notes.
Coffee can be good in many different ways, from
So coffee quality is often measured according to the standards of the CQI (Coffee Quality Institute) that produces the Q grader certification. Graders taste the coffee and score it on many metrics before putting the score as a number between one and one hundred. Traditionally 80+ was considered the threshold for 'specialty' coffee. But there are many, many kinds of coffee that make it to 80+ - all great but in different ways.