Olive trees bloom and create fruits at the beginning of summer.
Throughout summer, it grows its fruits with solar energy and earth minerals.
Olive fruits are green during the summer. In Autumn their colours first change into yellow, then pink, then purple and black when it is ripe.
Polyphenols which protects the unripe fruit from birds become fewer as the fruit ripens.
As the name suggests, Early harvest is harvesting olives before the standard harvest time meaning harvesting unripe olives.
Phenolic components add a bitter taste and a sting on the tongue to the oil.
Bitterness is something gourmets look for in olive oil just like they do in dark chocolate. Bitterness and sting can be lower or higher based on cultivars, harvest time, tree care (higher in unwatered unkept trees), oil extraction method.