Gene Krenzer, Small Grains Extension Specialist
Department of Plant and Soil Sciences
Division of Agricultural Sciences and Natural Resources
Oklahoma State University

This publication gives an introduction of hard white wheat as a potential specialty crop for the state of Oklahoma. The goals are to increase awareness of white wheat by highlighting its strengths and weaknesses and to indicate some important production practices required for white wheat to be successful in Oklahoma.

To increase profits, Oklahoma farmers are evaluating alternative crops. Producing hard white wheat in an identity preserved system is one alternative. An identity preserved system is one where the identity of a product can be maintained from planting seed to finished product. An example might be buying and planting certified Intrada seed. The wheat is harvested and kept separate from any other wheat. The wheat is delivered to a location where it is either kept isolated or co-mingled only with other Intrada, or co-mingled with other specified white wheat varieties, and finally made into flour.

Hard white wheat is similar in many ways to hard red winter wheat. The plants are similar and both have hard grain endosperm for making bread. However, the color of the seed coat (bran) is different. Bran color is determined by three major genes that do not affect other plant traits. Many modern varieties of hard red winter wheat have only one or two of these genes for red bran. White wheat, in contrast, has no major genes for red bran color and therefore is white.

Advantages of hard white wheat are not fully known. In some international markets, millers, bakers, and consumers prefer white wheat whenever they have a choice. With rising publicity of this preference, interest has increased in the domestic and/or export market potential for hard white wheat. Marketability is very important to the producer.

Major food uses for white wheat include tortillas, pita, regular and whole wheat breads, buns, and Asian noodles. Currently, around 50 percent of the wheat flour in Asia is being converted into noodles. Fresh noodles made from hard white wheat are lighter in color, a characteristic preferred by Asian consumers. Hard white wheat is also a good choice for the Middle Eastern bulgur dish and for couscous, a staple of North Africa that is growing in popularity in the U.S. Furthermore, hard white wheat is the most desirable option for pasta manufacturers who use farina from hard wheat instead of semolina from durum wheat.

The food industry receives several benefits from white wheat that in turn are expected to increase demand:

• White bran imparts a less bitter taste than red bran. Also white bran is less obvious than red bran in flour and food products. Therefore, hard white wheat is preferred over hard red wheat in countries where a high percentage of the wheat bran is included in the flour.
  
  
• White wheat can be milled at a slightly higher extraction rate, yielding more flour than red wheat, making each bushel of white wheat more valuable. Millers can extract 1 to 2 percent more flour without darkening the flour color. It has been estimated that this greater extraction rate could be worth an additional five to seven cents per bushel. However, this additional extraction rate is frequently not obtained because mills are milling to a certain ash content regardless of whether they are milling red or white wheat.
  
  
• Whole hard white wheat flour or hard white bran can be used instead of non-wheat materials to increase fiber content of many existing products without altering color or flavor.
  
  
• Researchers have found that bread dough requires less sugar when it is made with white wheat flour instead of red wheat flour.
  
  
• Bran from white wheat is a co-product rather than a by-product, meaning it may have value as human food rather than primarily as animal feed.

POTENTIAL PROBLEMS FOR HARD WHITE WHEAT

Disruption of wheat movement through grain handling and marketing channels is a primary concern of introducing white wheat into Oklahoma. Any producer considering the production of white wheat may want to have a contract for grain delivery before planting white wheat. Currently, contracts are offering a premium, but producers need to read the contract carefully. There may be a very small premium for white wheat and the remainder of the premium offered is for meeting certain specifications on dockage, test weight, and/or protein content. If a contract specifies minimum quality for delivery, what does it say about disposition of wheat not meeting the minimum standard? Contracts may also designate the variety to be grown or seed source, or verification of certified seed being planted.

Quantity of white wheat produced in an area is another issue. An elevator operator or miller is unlikely to accommodate a new class of wheat unless a sizable quantity is available. A final factor is whether there is sufficient quantity for efficient trans-portation from elevators to mills or export market points.

Mixtures of white and red wheat can interfere with wheat marketing. In many cases these mixtures can result in significant discounts. Mixtures can occur anywhere in the chain from seed producer to consumer, but two primary concerns are mixtures in the field and in equipment. To keep from having mixed wheat, white wheat should not be planted in a field where red wheat was grown the previous year. Drills, trucks, combines, and bins should be thoroughly cleaned before using for white wheat.

Elevators must also segregate white wheat from red wheat in handling and storage, because mixed wheat sells at a discount. Therefore, an identity preserved system is probable as white wheat is introduced in an area.

Mixing hard red winter wheat and hard white wheat may cause the grade to be lowered. The official grading standards define hard white wheat as a contrasting class from hard red winter wheat. In Table 1, we can see that just 2% red wheat in a load of white wheat would reduce the grade to U.S. No. 2 and 3% makes it U.S. No. 3. Therefore, 3% red wheat in a load of hard white wheat could cause it to be rejected if the contract called for U.S. No. 2 hard white wheat. This means that if volunteer wheat results in 3 out of every 100 heads in the field being red wheat, the truck load would be graded U.S. No. 3 even if all other grading factors were okay for U. S. No. 1.

Preharvest sprouting of current hard white wheat varieties may be a higher probability in certain parts of Oklahoma and Kansas than hard red wheat varieties. After maturity, if rainfall, high humidity, and lower-than-normal temperatures delay harvest, the white wheat varieties sprout in the head more readily then most red wheat varieties. Preharvest sprouting indicates increased enzyme activity and starch degradation in the grain, destroying the bread-making ability of wheat. Therefore, wheat containing sprout damage may be discounted or classified sample grade (Table 2). Such wheat is generally sold for livestock feed at much lower prices than US No. 2 Hard Red Winter Wheat or Hard White Wheat.

When introducing a new crop, it is very important to grow it in areas where it has the highest probability of success. In Oklahoma, preharvest sprouting is least likely in the panhandle and Northwestern Oklahoma because environmental conditions are more arid during harvest than in other parts of the state. The map on page 10 indicates the area that has the highest probability of being able to grow white wheat without sprout damage. Overcoming preharvest sprouting susceptibility is a major goal of wheat breeding programs in Oklahoma and Kansas and hopefully it can be reduced in wheat varieties released in the future.

Australia is currently the major producer and supplier of hard white spring wheat. China produces a significant amount of hard white winter wheat. In the U. S., California, Montana, and Kansas are the major producers of hard white wheat. Several other states including Washington, Montana, New York, and Oregon produce soft white wheat (Figure 1).

Currently, the U.S. wheat ports are:

St. Lawrence and Lakes for durum, hard red spring, soft red winter, and soft white.

Atlantic for soft red winter.

Pacific for both hard and soft white wheat , hard red spring, hard red winter, durum.

Gulf for hard red winter, soft red winter, durum, and hard red spring.

Most wheat exported from Oklahoma moves through the Gulf. Therefore, if the Great Plains area were to produce white wheat, the Gulf port would have to accommodate an additional class of wheat.

Oklahoma producers interested in growing hard white wheat must avoid mixing hard white wheat with hard red wheat. Volunteer red wheat, wheat germinating from seed left from last year’s planting or harvest, must be eliminated when hard white wheat is planted after hard red wheat or vice versa. This is best accomplished by not growing wheat in a particular field the year before switching from red to white wheat. Drills, combines, hauling equipment, and storage areas must be cleaned extremely carefully. If seed is kept for planting the next year’s crop, then one class should be harvested from areas no closer than 20 feet away from fields of any other class. All production practices (seeding date, seeding rate, fertilization, and harvesting) are alike for hard white and hard red winter wheat. The same equipment is used for both crops.

Grain of hard white wheat should be harvested promptly after it ripens to avoid exposure to wet, humid weather. White wheat should be harvested first, if both hard white wheat and hard red wheat are being grown and ripen simultaneously. Grain that has sprouted extensively should not be used for seed.

Currently several hard white wheat varieties are being grown on small acreage in the southern Great Plains. Arlin, Betty, Heyne, Intrada, Oro Blanco, and Trego have been or are currently being tested in the OSU wheat variety trials. Tables 2-4 include data from 1998 to 2000 forage and grain harvest. From these data we conclude that there are hard white wheat varieties comparable in grain yield, test weight, and fall forage yield to the best hard red winter varieties currently grown in Oklahoma.

Some premium for hard white winter over hard red winter wheat might be expected. However, even without a premium, producers could still benefit from greater diversity in market opportunities of white wheat.

As white wheat becomes more available, the uses of hard white wheat will be explored more thoroughly. Currently at Oklahoma State University, a group of employees are working with value added products in the new Oklahoma Food and Agricultural Research and Technology Center. White wheat is one of the crops receiving attention. A noodle machine was recently acquired in the baking room. This machine will be used for research on Asian noodles. Asian noodles are becoming very popular and this could be a large market for white wheat here in Oklahoma. Continued research in utilization of white wheat is important to its success.