The Wheat Family, from Wild Grass to Flour

Start with the oldest of the line. Einkorn is a diploid hulled wheat with a single grain in each spikelet, it is not a hybrid, and DNA evidence traces its domestication to near Karaca Dag in southeastern Turkey roughly 10,000 years ago.

Emmer descends from wild tetraploid wheat, itself a hybrid of two wild grasses, and became fully domesticated in the Pre-Pottery Neolithic B period. It later served as the main wheat of Pharaonic Egypt and survives today as a relict crop in mountain regions.

Spelt was cultivated from the Neolithic onward and was a staple in parts of Europe from the Bronze Age to the Middle Ages. It is sometimes considered a subspecies of common wheat, most likely a hybrid of wheat and emmer, and is still eaten in Central Europe and northern Spain.

Farro is a kitchen name rather than a single species: in Italian cuisine it covers einkorn, emmer and spelt as small, medium and large farro. It links the three stops before it, and emmer is regarded in Tuscany and Abruzzo as the true farro.

Khorasan wheat is a tetraploid with grains about twice the weight of modern wheat. Its name points to the historical region of Khorasan, and its rediscovery in the United States by a Montana farmer led to the trademarked brand Kamut.

Triticale marks the point where people bred new grains on purpose. It is a cross of wheat and rye first made in the late nineteenth century, sterile until colchicine doubled its chromosomes in 1937, and its first commercial variety reached growers in 1970.

Now the kernel meets the mill. Flour is any ground grain, root, bean, nut or seed, with wheat flour the most common for bread. Whole grain flour keeps the endosperm, germ and bran, while refined flour keeps only the endosperm.

Bran is what refining takes away: the aleurone and pericarp around the endosperm, removed when grain becomes white flour. It is dense in fiber and also gets used in breakfast cereals, in muffins and, as rice bran, in Japanese pickling as nuka.

Bulgur takes a different route from flour. Raw wheat is parboiled, dehulled, dried and cracked, and the coarse and fine grades go into pilafs, kibbeh and tabbouleh. Food historian Gil Marks places its origin around 4000 BC in the ancient Middle East.

Semolina is a coarse flour milled from durum wheat, with a high protein and gluten content that suits pasta. It also goes into couscous, Indian upma and halwa, and the Middle Eastern cake basbousa.

Freekeh ends the path with fire. Green durum wheat is harvested while soft, sun-dried, then set alight so only the straw and chaff burn. The name comes from the Arabic farik, meaning rubbed, and the dish belongs to the Levant and North Africa.