There are several species of Coffea that may be grown for the beans. The trees produce red or purple fruits called "cherries" that are drupes. The cherries contain two seeds, the so-called "coffee beans", which — despite their name — are not true beans. In about 5-10% of any crop of coffee cherries, there is only a single bean, rather than the two usually found. This is called a peaberry, which is smaller and rounder than a normal coffee bean.
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