An orange is the fruit of several citrus species that belong to the family Rutaceae (see a list of orange-related plants). It mostly means Citrus sinensis. All citrus trees are in the same genus and are almost entirely interfertile.
Grapefruits, lemons, limes, oranges, and a variety of hybrids fall under this category. Citrus taxonomy is highly contentious, ambiguous, or inconsistent due to the numerous hybrids, cultivars, and bud mutations that have been selected as a result of orange and other citrus interfertility.
From spherical to oblong, sweet oranges grow in a variety of sizes and shapes. The white, bitter mesocarp, or albedo (pith), is a porous white tissue inside that is attached to the rind.
The fruit is green when it is not ripe. The ripe fruit’s grainy, irregular rind can be bright orange to yellow-orange, but it frequently retains green patches or, in warm climates, stays completely green. Like any remaining citrus natural products, the sweet orange is non-climacteric.
There are four distinct classes of Citrus sinensis with distinct characteristics: blood or pigmented oranges, navel oranges, acidless oranges, and common oranges