SOMETHING ABOUT GRAIN
About 95% of the wheat produced in the world is common wheat (Triticum aestivum), also known as bread wheat. Bread wheat is an allohexaploid (an allopolyploid with six sets of chromosomes: two sets from each of three different species). Of the six sets of chromosomes, two come from Triticum urartu (einkorn wheat) and two from Aegilops speltoides. This hybridisation created the species Triticum turgidum (durum wheat) 580,000–820,000 years ago. The last two sets of chromosomes came from wild goat-grass Aegilops tauschii 230,000–430,000 years ago.
Durum wheat, also called pasta wheat or macaroni wheat (Triticum durum or Triticum turgidum subsp. durum), is a tetraploid species of wheat. It is the second most cultivated species of wheat after common wheat, although it only represents 5% to 8% of global wheat production.
Durum Wheat was developed by artificial selection of the domesticated emmer wheat strains formerly grown in Central Europe and the Near East around 7000 BC, which developed a naked, free-threshing form. Like emmer, durum wheat is awned (with bristles). It is the predominant wheat that grows in the Middle East.
Durum in Latin means “hard”, and the species is the hardest of all wheats. This refers to the resistance of the grain to milling, in particular of the starchy endosperm, implying dough made from its flour is weak or “soft”. This makes durum favorable for semolina and pasta and less practical for flour, which requires more work than with hexaploid wheats like common bread wheats. Despite its high protein content, durum is not a strong wheat in the sense of giving strength to dough through the formation of a gluten network. Durum contains 27% extractable, wet gluten, about 3% higher than in common wheat (T. aestivum L.).
Emmer wheat, also known as farro especially in Italy, or hulled wheat, is a type of awned wheat. Emmer is a tetraploid (2n=4x=28 chromosomes).
Along with einkorn wheat, emmer was one of the first crops domesticated in the Near East. It was widely cultivated in the ancient world but is now a relict crop in mountainous regions of Europe and Asia.
Classes of flour used in the United States
The classes used in the United States are:
- Durum – Very hard, translucent, light-colored grain used to make semolina flour for pasta & bulghur; high in protein, specifically, gluten protein.
- Hard Red Spring– Hard, brownish, high-protein wheat used for bread and hard baked goods. Bread Flour and high-gluten flours are commonly made from hard red spring wheat.
- Hard Red Winter– Hard, brownish, mellow high-protein wheat used for bread, hard baked goods and as an adjunct in other flours to increase protein in pastry flour for pie crusts. Some brands of unbleached all-purpose flours are commonly made from hard red winter wheat alone. One variety is known as “turkey red wheat”, and was brought to Kansas by Mennonite immigrants from Russia.
- Soft Red Winter– Soft, low-protein wheat used for cakes, pie crusts, biscuits, and muffins. Cake flour, pastry flour, and some self-rising flours with baking powder and salt added, for example, are made from soft red winter wheat. Hard White – Hard, light-colored, opaque, chalky, medium-protein wheat planted in dry, temperate areas. Used for bread and brewing.
- Soft White– Soft, light-colored, very low protein wheat grown in temperate moist areas. Used for pie crusts and pastry. Pastry flour, for example, is sometimes made from soft white winter wheat.
Flour type numbers
- German flour type numbers (Mehltypen) indicate the amount of ash (measured in milligrams) obtained from 100 g of the dry mass of this flour. Standard wheat flours (defined in DIN10355) range from type 405 for normal white wheat flour for baking, to strong bread flour types 550, 812, and the darker types 1050 and 1600 for wholegrain breads.
- French flour type numbers (type de farine) are a factor 10 smaller than those used in Germany, because they indicate the ash content (in milligrams) per 10 g flour. Type 55 is the standard, hard-wheat white flour for baking, including puff pastries (“pâte feuilletée”). Type 45 is often called pastry flour and is generally from a softer wheat (this corresponds to what older French texts call “farine de gruau”). Some recipes use Type 45 for croissants, for instance, although many French bakers use Type 55 or a combination of Types 45 and 55. Types 65, 80, and 110 are strong bread flours of increasing darkness, and type 150 is a wholemeal flour.
The table shows some typical examples of how protein and ash content relate to each other in wheat flour. This will help you to find the correct type of flour to be used.
Ash | Protein | US | UK | German | French | Italian | Argentinian |
~0.4% | ~9% | pastry flour | soft flour | 405 | 40 | 00 | 0000 |
~0.55% | ~11% | all-purpose flour | plain flour | 550 | 55 | 0 | 000 |
~0.8% | ~14% | high gluten flour | strong or hard | 812 | 80 | 1 | 00 |
~1.1% | ~15% | first clear flour | very strong or hard | 1050 | 110 | 2 | 0 |
>1.5% | ~13% | white whole wheat | wholemeal | 1600 | 150 | Farina integrale di grano tenero | ½ 0 |
This table is only a rough guideline for converting bread recipes. Since flour types are not standardized in many countries, the numbers may differ between manufacturers. Note that there is no Type 40 French flour. The closest is Type 45.
It is possible to determine ash content from some US manufacturers. However, US measurements are based on wheat with a 14% moisture content. Thus, a US flour with 0.48% ash would approximate a French Type 55.