© Denzil Green
Yams are very long tubers (up to several feet long.) They are cylindrical-shaped, with rough, brown scaly skin that looks a bit like tree bark.
Most varieties of yams are too large to sell whole in supermarkets. They will be sold in chunks weighing a pound or two each, sealed in plastic. The flesh should be firm, and any skin on the chunks you are buying should be tight and free of wrinkles. Canned yams are equally acceptable.
In the UK and in North America, unless the yam you are buying either is canned or is being sold as has just been described, what you buying is a sweet potato mislabelled as a yam. Sweet potatoes look like potatoes, in size and skin, except they have tapered ends.
Yams are tropical roots native to Africa, but now grown around the world. They will not grow in temperate climates such as North America and the UK. Most yams are mostly imported from the Caribbean.
The plant is a vine with climbing stems, leaves and flowers. There are more than 150 varieties of yams, varying inside colour from white to purplish to brownish; the skin colour may be dark brown or off-white.
The roots need 12 months to mature before they are ready to harvest.
When cooked, the flesh may be moist or dry, fine or coarse or grainy. Some varieties are sweeter than others; some are bitter.
Wash and peel yams as you would potatoes, and prepare and use them as you would sweet potatoes – for boiling, mashing, braising, grilling, roasting, baking or frying.
Some varieties of yams, namely the bitter ones, can be toxic if eaten raw. Japanese varieties of yams such as Yamaimo are an exception.
Unlike sweet potatoes, which are the champion veg for vitamin A, yams do no contain any vitamin A.
Yams may be stored in a cool, dark, dry location for up to two weeks. Do not store them in the refrigerator.
Yams should be stored in a cool, dark, dry area. They can be safely kept for up to two weeks. Uncooked yams should never be refrigerated. Cooked yams can be refrigerated for 3 days.
Yams originated in Asia, and came to Africa around the 1st century AD, and were brought to the Caribbean with the slave trade.
Literature & Lore
“Yam” comes from the West African word, nYami, meaning “to eat”.