yam v. sweet potato

Yams are starchy tubers native to Africa and Asia, and can be as large as 2.5 m with a weight up to 70 kg. Sweet potatoes are indigenous to South America, and are much smaller than yams. In North America, where orange and white sweet potatoes are cultivated, the orange variety is misleadingly called a ‘yam’ to help differentiate them. True yams and sweet potatoes are not closely related:

Taxon	Yam	Sweet Potato
Kingdom	Plantae	Plantae
Phylum	Angiosperms	Angiosperms
Class	Monocots	Eudicots
Order	Dioscoreales	Solanales
Family	Dioscoreaceae	Convolvulaceae
Genus	Dioscorea	Ipomeoea
Species	several	batatas

 

White sweet potatoes have a thin, yellow skin and pale white flesh, aren’t sweet after cooking, and have a dry, crumbly texture. Orange sweet potatoes have a thicker, dark orange skin and bright orange flesh, and are sweet and moist when cooked. Actual yams are sweeter and moister than either type of sweet potato.

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