Wheat's Role in the U.S. Diet
Wheat's Role in the U.S. Diet Has Changed Over the Decades
U.S. consumption of wheat products-such as breads, pastas, and pizza-dropped sharply beginning in 2000, reversing a three-decade trend of growth in per-capita consumption. Wheat consumption fell from an estimated 146.3 pounds per person in 2000 to a low of 133.4 pounds in the mid-2000s, recovered slightly, then dropped back to 132.5 pounds per person for 2011. The drop from 2000 reflected public interest in lowering carbohydrate consumption. Interestingly, the rise in wheat consumption that started some 30 years ago was also triggered by health concerns. In the 1970s, American began shifting from animal products to grain-based foods, including wheat products, because of concerns about cholesterol and heart disease.
Historical data indicate that there have been previous periods of growth and decline in wheat consumption. From a low starting point in the 1600s, consumption of wheat flour rose to about 225 pounds per capita in 1880, and then fell to about 110 pounds a century later. These shifts reflected supply-side factors-including changes in wheat production, milling, and transportation-in addition to demand for more diversified diets.
Yeast Breads Limited in Colonial America
Wheat production was difficult in New England and in much of the South in the colonial era (1600s and 1700s), making wheat flour too expensive for regular use. High transportation costs also made long-distance transport of wheat and flour from regions better suited for wheat growing unprofitable. Therefore, colonists in these regions turned to other crops, especially corn. The wealthy were the principal consumers of wheat bread.
The high cost of wheat flour was not the only factor favoring cornmeal breads. Most baking took place either in Dutch ovens or in reflector ovens placed in the fireplace until the invention of the cast iron, wood-fired cook stove in the 19th century. For homes without these stoves, it was easier to deal with cornmeal and nonyeast bread products prepared as baked-hearth flat breads.
Flour Cost Begins Falling in 18th Century
Milling costs dropped when Oliver Evans developed an improved milling system in 1790. This system took the wheat to the top of the mill by mechanical power, and carried it down by gravity through the grinding process. The Evans system reduced the labor needed in a mill by more than half. It also increased the flour-extraction rate from wheat. Cyrus McCormick's invention of the reaper in 1834 and the development of John Deere's steel plow in 1837 reduced production costs and stimulated wheat production. The reaper eliminated manual cutting of the crop and the steel plow greatly accelerated the rate at which the heavy prairie soils could be tilled.
In addition, early improvements in transportation infrastructure helped reduce flour cost to U.S. consumers, especially in areas where wheat was not widely grown. One early improvement was the Erie Canal. Later, railway expansion made a substantial difference. At mid-century, rail transport was one-tenth the cost of hauling grain overland by road.
New Hard Wheat Flours Support Consumer Demand in Second Half of 19th Century
Demand for bread was stimulated by the introduction of hard wheats and new milling techniques that changed the quality of the flour. Because hard wheats have higher protein content (see box), they were better suited for making bread than soft wheat.
Protein and Bread Making
The essential ingredients for leavened bread are flour, water, and yeast. As these ingredients are mixed together, enzymes in the yeast and flour cause starch to break down into simple sugars. Yeast metabolizes these simple sugars and releases carbon dioxide. With kneading, unique proteins in wheat flour form a sticky, stretchy substance called gluten. If the dough has a strong gluten network, the released carbon dioxide bubbles are held within the gluten, thereby inflating the dough. This rising of the dough creates the airy texture of bread. If the protein level of the wheat flour is too low, little gluten is formed, the carbon dioxide will escape and the dough will not rise enough to create the desired texture. About 11.5-percent wheat protein is necessary for common pan bread.
Until the 1870s, nearly all U.S. wheat production consisted of soft wheat varieties. A hard spring wheat variety (originally from Central Europe) with a higher protein content was introduced in Minnesota in mid-1800s. Westward expansion of the rail system allowed increasing quantities of hard wheat flour to move to the East after 1865. A little later, Mennonites from the Crimea brought with them a hard winter wheat variety when they immigrated to Kansas, where the main crop was corn. By 1890, Kansas was becoming an important wheat-producing State by growing hard wheat. Milling durum wheat produced in North Dakota began in 1904. After a few years, U.S. macaroni manufacturers switched away from imported durum.
When the new hard spring wheat was introduced, U.S. millers initially milled this grain with millstones. The resulting flour was not very desirable. When wheat was ground between millstones, all parts of the kernel were ground down together. When the resulting product was sifted through cloth, some of the smaller brownish particles of bran and the more yellowish parts from the germ (or embryo) also passed through. The stone-ground flour was therefore creamy in color with flecks of brown.
In 1880, millstone grinding was replaced by steel roller mill technology from Hungary. Roller mills provided a cleaner separation of the starch from the outer bran layers of the kernel, and the nearly complete removal of the germ and its oil. The result was finer, whiter flour, which was highly valued by bread consumers. In addition, removal of the oil in the germ, which spoils quickly, and bran, which absorbs moisture, made a flour with longer shelf life.
New Wheat Products Change Breakfast in America
Historically, economic development has been accompanied by the substitution of meat for grain in the diet, and this was true in the United States. Then, in the late 19th century, breakfast-food manufacturers began promoting grains for breakfast. They convinced people to substitute highly processed grains for meat as a healthy and convenient alternative.
John Harvey Kellogg had begun experimenting with breakfast cereals in the 1870s, introducing a whole-wheat breakfast cereal in 1880 as a health-food product. This breakfast cereal was eventually named granola. Later, the Kellogg brothers created a wheat-flake breakfast cereal, called Granose, also as a health-food product. C.W. Post developed Postum in 1895 and then Grape-Nuts in 1898.
Cooked grain (porridge) was a common dish among the European immigrants in America in Colonial times. The Quaker Oats Company produced oatmeal, the first successful ready-to-cook cereal, in the 1870s. Later, Thomson Amidon discovered coarsely ground wheat could also be cooked into a breakfast cereal. Because of its color, he called it Cream of Wheat.
With new technologies, new products, and improved infrastructure-and the resulting lower costs-flour consumption rose during the 19th century. During the closing decades, consumption remained at very high levels as new and improved wheat products were introduced.
Flour Consumption Declines for the First Two-Thirds of the 20th Century
From 1890 until 1920, the greatest increase in food consumption occurred with sugar, and the greatest decrease was in cornmeal. Rising prosperity led to a pronounced shift from cornmeal to wheat flour, especially in the South, and an equally important substitution of sugar for wheat flour. Sugar prices had been dropping sharply since the 1850s with the development of improved refining technology.
After 1920, the substitution of wheat flour for cornmeal slowed, but per capita wheat flour consumption continued to drop. Part of the reason was a decrease in total per capita food requirements as fewer people engaged in heavy physical labor. Another factor was further substitution of sugar for flour in the diet. Moreover, diets were becoming more diversified to include more eggs, milk, fruits, and vegetables. Prices of these items fell as agriculture became more mechanized and transportation improved, making distribution more efficient. Refrigerated railway cars, for example, were especially important for perishable foodstuffs. This more expensive diet was also supported through rising consumer prosperity and increased awareness of the health benefits of a more diversified diet.
The decline in per capita wheat consumption slowed during the Great Depression and the world wars. After World War II, the decline resumed as people continued to diversify their diets. Supermarkets offered an increasing range of foodstuffs, and rising incomes allowed consumers to diversify their diet with more expensive food items.
A striking change in wheat flour use occurred in the past century. At the turn of the 20th century, home baking accounted for 90 percent of total flour consumption, with commercial bakeries accounting for 10 percent. By 1945, the bakery portion rose to 60 percent as home baking dropped with the entry of women into the workforce. By 1990, less than 10 percent of flour was consumed in the home.
Wheat-Product Consumption Starts To Rise Again in the 1970s
The decline in wheat consumption slowed during the 1960s, partly because consumers became increasingly aware of possible links between a diet high in animal products and cholesterol. Wheat products were viewed by many consumers at the time as a healthy, alternative food choice.
The rapid expansion of the fast-food industry also boosted per capita consumption of wheat products. These businesses, providing items such as sandwiches, hamburgers, breaded chicken, pizza, and bagels, spread rapidly in the 1970s and 1980s.
Fast food's popularity stemmed from many factors, including:
- Reduced food preparation time, which became increasingly important as more women entered the work force
- Greater number of people living alone and lacking the incentive to cook for one
- Convenience of fast-food restaurants, particularly for lunch
- Rising disposable incomes
- Relatively reasonable prices
These trends helped increase per capita wheat product consumption in the United States for the last quarter of the 20th century.
Wheat Product Consumption Levels Out as the United States Enters the 21st Century
Between 1972 and 1997, U.S. wheat producers and millers could count on rising per capita food use of wheat flour to expand their domestic market. The decades-long growth ended in 1997 as changing consumer preferences, led by the adoption of low-carbohydrate diets, reduced per capita wheat consumption. Consumer interest in these diets spiked after 2000. Per capita flour use dropped rapidly at first and then fell more slowly until reaching a low of 132.5 in 2011.