The blend makes the espresso
"Blend" is the name given to a mixture of different coffee beans. For espresso coffees in particular, a wide variety of beans from all over the world are combined with each other in order to combine the best properties to create the perfect end product. It is important that the individual coffees are roasted separately. Since each batch has its own characteristics, an optimal result can only be achieved through separate roasting.
Although Arabica beans are often rated better in terms of taste, high-quality Robusta can come up with a better, fuller body. Comparable to a good wine cuvee. It is the clever ratio of the different bean characters that gives espresso coffee a balanced and distinctive taste. If, on the other hand, you try single-origin coffees, you can recognize the characteristics of the beans more clearly, but you don't have the range and fullness of aroma of a blend.
A relatively common blend ratio of 80% Arabica to 20% Robusta, for example, results in a well-balanced espresso blend, such as Salimbene Superbar, which is sure to please even Robusta doubters.
But of course, the same applies to coffee roasts: the proof of the pudding is in the eating!