Orange aromatics and flavors are prized in coffee, whether they take the form of sweet orange flesh and pulp, or orange peel.
Orange flavors or aromatics can range in degrees of ripeness, which also involves a shift in levels of brightnessA euphemistic term we use often to describe acidity in coffee. A bright coffee has more high, acidic notes. : A euphemistic term to describe acidity in coffee.... and sweetnessSweetness is an important positive quality in fine coffees, and is one of five basic tastes: Sour, Sweet, Salty, Bitter, Savory (Umami). In coffee, sweetness is a highly....
As you might agree from your own experience, a very ripe orange has milder acidityAcidity is a positive flavor attribute in coffee, also referred to as brightness or liveliness. It adds a brilliance to the cup, whereas low acid coffees can seem... and increased sweetness. Coffees with orange suggestion range from the less ripe, more tart acidity, with less sweetness to moderate the tartness. And some show a milder acidity with high sweetness reminiscent of the ripest oranges, or types like blood orange which seem (to me) to have high sweetness and less tartness.
Some orange notes or aromas veer into the tangerine / mandarin zone.