Kernza

Intermediate wheatgrass is a tall, cool-season perennial grass with long seed heads and extensive roots that can reach more than two metres deep. Each plant lives for several years, regrowing after harvest without replanting. The grain, marketed under the trademark Kernza, is much smaller than wheat, with a slender kernel that is brown to tan and wrapped in a hull that is removed during cleaning. The flavour is nutty and slightly sweet, with a hint of rye or whole wheat. Kernza is sold as whole grain, flour, flakes, and in products such as beer, bread, crackers and cereal. The flour is darker than refined wheat, and its gluten differs from bread wheat.

Thinopyrum intermedium is native to Europe and western Asia, where it grows in grasslands and steppes. It was introduced to North America in the twentieth century as a forage and conservation grass. The name intermedium refers to its position between related wheatgrass species. The Kernza name was coined by The Land Institute in Kansas, which has bred the plant for grain since 2003. The aim is a perennial crop that can offer grain while protecting soil and water, using traditional breeding for larger seed and higher yield.

In the 1980s the Rodale Institute in Pennsylvania screened many perennial grasses for grain potential, and intermediate wheatgrass emerged as a promising candidate because of its seed size, flavour and vigour. The United States Department of Agriculture had earlier tested the grass as a forage. In 2001 the Land Institute, founded by Wes Jackson to promote perennial grain agriculture, began a breeding programme, selecting plants with larger seeds, easier threshing and better yield over successive generations. The University of Minnesota also became a major partner, running one of the largest breeding programmes. By the 2010s farmers in the American Midwest were growing Kernza in limited acreage, and in 2016 a beer made with it brought public attention. General Mills, Patagonia Provisions and small bakeries and breweries have launched products. Researchers are studying its effects on soil carbon, erosion and nitrate loss, and efforts continue to raise yield, which is still lower than annual wheat. Programmes are also under way in Europe, including in Germany and Sweden.

Kernza grain is milled into flour for breads, pancakes, crackers and pastries, often blended with wheat flour because of its different gluten. Whole kernels can be cooked into salads and pilafs, and flakes make a porridge-like cereal. Brewers and distillers use Kernza in beers and spirits. Farmers grow it as a dual-purpose crop, harvesting grain and then grazing or cutting the straw and regrowth for forage. Its root system is also valued for erosion control and soil building on sloping or marginal land.

Kernza is a whole grain that provides protein, fibre and minerals, and early nutritional analyses suggest it compares favourably with wheat in protein and some micronutrients, though the small kernel means a high proportion of bran. Human studies on its health effects are limited, so benefits should not be overstated. Its main claim is environmental, relating to perennial agriculture, rather than clinical nutrition.