Citrus are usually self-fertile (needing only a bee to move pollen within the same flower) or parthenocarpic (not needing pollination and therefore seedless, such as the satsuma). A mature mandarin tree can yield up to of fruit. Mandarin orange fruits are small . Their colour is orange, yellow-orange, or red-orange. The skin is thin and peels off easily. Their easiness to peel is an important advantage of mandarin oranges over other citrus fruits. Just like with other citrus fruits, the endocarp (inner flesh) is separated into segments, which in their turn consist of a large number of elongated cells. The fruits may be seedless or contain a small number of seeds. Mandarin orange fruits are sweet to taste, and can be eaten as whole or squeezed to make juice. In 2017, world production of mandarin oranges (combined with tangerines, clementines, and satsumas in reporting to FAOSTAT) was 33.4 million tonnes, led by China with 54% of the global total (table). Producing more than one million tonnes each in 2017 were Spain, Turkey, Morocco, Brazil, and Egypt. Mandarins are generally peeled and eaten fresh or used in salads, desserts and main dishes. Fresh mandarin juice and frozen juice concentrate are commonly available in the United States. The number of seeds in each segment (carpel) varies greatly. The peel is used fresh, whole or zested, or dried as chenpi. It can be used as a spice for cooking, baking, drinks, or candy. Essential oil from the fresh peel may be used as a flavouring for candy, in gelatins, ice cream, chewing gum, and baked goods. It is also used as a flavouring in liqueurs. In Chinese cuisine, the peel of the mandarin orange, called chenpi, is used to flavor sweet dishes and sauces. Canned mandarin segments are peeled to remove the white pith prior to canning; otherwise, they turn bitter. Segments are peeled using a chemical process. First, the segments are scalded in hot water to loosen the skin; then they are bathed in a lye solution, which digests the albedo and membranes. Finally, the segments are rinsed several times in plain water. Once orange segments are properly prepared, mandarin oranges undergo heat processing to remove bacteria that can cause spoilage.