On top of the differences between the plants and the cultivation of these plants, each bean contains different levels of minerals and other chemical compounds.
For example, Robusta beans contain much more caffeine than the Arabica beans. Robusta beans contain 2.7% caffeine content. Contrast that with the 1.5% caffeine content found in Arabica beans and you see that Robusta, with almost double the caffeine content, are tailor made for those of us that love that boost that caffeine gives us in the morning. But caffeine content isn’t the only difference.