Solanum tuberosum (Potato)

Life > eukaryotes > Archaeoplastida > Chloroplastida > Charophyta > Streptophytina > Plantae (land plants) > Tracheophyta (vascular plants) > Euphyllophyta > Lignophyta (woody plants) > Spermatophyta (seed plants) > Angiospermae (flowering plants) > Eudicotyledons > Core Eudicots > Asterids > Euasterid I > Order: Solanales > Family: Solanaceae > Genus: Solanum

Potatoes. [image H. Robertson, Iziko ©]

Potatoes originate from South America where people have been cultivating them for more than 4000 years. They consist mainly of starch but also have at least 3% protein and some vitamin C. The green tissues in green potatoes contain substances called alkaloids which when consumed in large quatities are poisonous.

Origin

South America. Has been under cultivation for more than 4000 years in the mountainous areas of South America and was a staple food of the incas. Potatoes were brought back to Europe by Spanish explorers in about 1570. It was under cultivation in England and Ireland by about 1610 and soon became an important food crop. From about 1845-49 Late Potato Blight, caused by Phytophthora infestans (a fungus like organism but not in the Fungi), struck the Irish potato crops, resulting in famine and the death of about one million people and the emigration of about 1.5 million.

Uses

The tubers are cooked as a vegetable. Potatoes consist mainly of starch but also have at least 3% protein and some vitamin C. The blackening that sometimes develops in potatoes after cooking is caused by the reaction of iron ions with phenolic substances in the tuber. This blackening can be reduced by increasing the acidity of the water, for instance by adding half a teaspoon cream of tartar per pint of cooking water once the potatoes are half done.

Potatoes can be dry mealy types (more starchy with cells that separate from one another on cooking), suitable for mash or baking, or they can be waxy (cells more coherent after cooking), best used for recipes that require cut up bits of potato.

Beware of green potatoes

The green tissues in green potatoes contain substances called alkaloids which when consumed in large quatities are poisonous. The production of these alkaloids is stimulated by exposure to light and to either fairly warm or very cold temperatures. Cooking does not destroy these alkaloids so the best solution is to peal away the green tissues before cooking.