Eggplant (Solanum melongena), also known as aubergine or brinjal, is a cultivated crop with a mysterious past. A member of the Solanaceae family (like its American cousins potatoes, tomatoes and peppers), eggplant is believed to have been domesticated in India, China, Thailand, Burma or someplace else in southeast Asia. The first use of eggplant was probably medicinal rather than culinary: its flesh still has a bitter after-taste if it is not treated, despite centuries of domestication experimentation. Today there are approximately 15-20 different varieties of eggplant.
The domestication process increased the fruit size and weight, and altered the prickliness, flavor, and flesh and peel color, a centuries-long process which is documented in ancient Chinese literature. The earliest domestic relatives of eggplant described in Chinese documents had round and green fruits, while today's cultivars feature an incredible range of colors. Wild eggplant is prickly, an adaptation to protect itself from herbivores; the domesticated versions have few or no prickles, a trait selected by humans so that we omnivores can pluck them safely.
Eggplant's Possible Parents
The progenitor plant for S. melongena is still under debate. Some scholars pinpoint S. incarnum, a native of North Africa and the Middle East, that developed first as a garden weed and then was selectively grown and developed in south-east Asia. DNA sequencing reported in 2010 provides evidence that S. melongena is descended from another African plant S. linnaeanum, and that that plant was dispersed throughout the Middle East and into Asia. Other scholars suggest that the true progenitor plant has not been identified yet, but was probably located in the savannas of southeast Asia. Its place of domestication is still currently believed to have been southeast Asia.
The real problem in trying to resolve the domestication history of eggplant is that archaeological evidence supporting any eggplant domestication process is lacking--evidence for eggplant simply hasn't been found in archaeological contexts, and so researchers must rely on a set of data that includes genetics and historic information.
Ancient History of the Eggplant
Literary references to eggplant occur in Sanskrit literature, with the oldest direct mention dated from the third century AD; a possible reference may date as early as 300 BC. Multiple references have also been found in the vast Chinese literature, the earliest of which is in the Tong Yue, dated to 59 BC. The Tong Yue reference is a gardening tip; one should separate and transplant eggplant seedlings at the time of the Spring equinox.
Later documentation in Chinese records illustrates the changes that were wrought in eggplants: from round and small green fruit to large and long-necked fruit with a purple peel. Illustrations in Chinese botanical references dated between the 7-19th centuries AD document the alterations in eggplant's shape and size; interestingly, flavor was also selected for, as the Chinese botanists endeavored to remove the bitter flavor in the fruits.
Eggplant is believed to have been brought back to the attention of the Middle East, Africa and the West by Arabic traders along the Silk Road, beginning around the 6th century AD.
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