Appears in
On Food and Cooking

By Harold McGee

Published 2004

  • About

Flaxseed comes from plants native to Eurasia, species of Linum and especially L. usitatissimum, which have been used for more than 7,000 years as a food and to make linen fiber. The small, tough, reddish-brown seed is about 35% oil and 30% protein, and has a pleasantly nutty flavor and an attractively glossy appearance. Two qualities set it apart from other edible seeds. First, its oil is over half linolenic acid, an “omega-3” fatty acid that the body can convert into the healthful long-chain fatty acids (DHA, EPA) found in seafoods. Flax oil (also known as linseed oil, and valued in manufacturing for drying to a tough water-resistant layer) is by far the richest source of omega-3 fatty acids among plant foods. Second, flaxseed is about 30% dietary fiber, a quarter of which is a gum in the seed coat made up of long chains of various sugars. Thanks to the gum, ground flaxseed forms a thick gel when mixed with water, is an effective emulsifier and foam stabilizer, and can improve the volume of baked goods.