Baking Sure New Wheats Measure Up
Wheat breeders, farmers, millers, and bakers have special problems in
meeting the challenges associated with delivering our daily bread to our dinner
Millers and processors demand varieties developed for specific end uses.
Information needed for every stage of production is available from four
ARS wheat quality laboratories located in
Manhattan, Kansas; Wooster, Ohio; Fargo, North Dakota; and Pullman, Washington.
These laboratories were established to help breeders improve the quality of
wheat varieties grown in their respective regions. The labs were charged with
determining what factors are important to wheat quality and developing reliable
tests for measuring these factors.
Before a new wheat seed is ever made available to growers, the researchers
at these quality labs have thoroughly analyzed the milling and baking quality
of thousands of experimental breeding lines from federal, state, and private
For Bread and BunsHard Winter Wheat
Each year, at the Hard Winter Wheat Quality Laboratory in Manhattan, Kansas,
researchers evaluate about 5,000 hard winter wheat samples from 3 federal
regional breeding nurseries and 18 state and private breeders. Hard winter
wheat is used to make white pan bread and hot dog and hamburger buns.
To obtain accurate information, the Manhattan researchers have adapted two
powerful analytical tools: near-infrared reflectance and single-kernel wheat
The quality of pasta made from semolina--the purified middlings of milled durum
wheat--is an important consideration in breeding new varieties. To evaluate the
semolina, physical science technician Jadene Wear extrudes spaghetti, which
will be dried and test-cooked.
The data on protein, moisture, and ash from these predictive measurements
and from biochemical analyses help ARS food technologist Bradford W. Seabourn
and chemist Okkyung Kim Chung develop end-use quality prediction equations. The
analyses show the relative quantity and composition of proteins, lipids,
enzymes, and starches in many wheat lines so that scientists can see how these
differ and how the differences between varieties are related to the differences
in end-use quality.
In 1998, Seabourn, Chung, and South Dakota State University researchers
developed a relational database now available to breeders through the World
Wide Web. Instead of poring through a thick publication, breeders can opt for a
user-friendly computer file to zero-in on a wheat line's major deficiencies and
rank each line based on its milling and baking qualities.
Because protein plays a major role in the quality of bread each wheat
variety produces, ARS chemist George L. Lookhart has adapted capillary
electrophoresis to quickly identify protein patterns as genetic fingerprints.
These can be used to distinguish between varieties and to predict end-use
Lookhart also developed a fast method for measuring the amount of insoluble
polymeric protein. The more there is in a wheat, the better the dough-mixing
properties of its flour.
One important accomplishment has been the adaptation of methods using small
quantities of flour for a mixograph analysis of dough strength. These methods,
which have reduced the flour needed from 35 grams to 5, permit earlier
evaluation of potential varieties.
"Occasionally, breeders can't supply enough flour from their
experimental wheat lines to perform adequate baking tests. To overcome this
problem, we designed thimble-sized baking pans that hold tiny loaves made from
only 2 grams of flour," says ARS baker Margo S. Caley in Manhattan.
"Our location in the Great Plains is important to our
customersthe growers and breeders of hard winter wheat," says Chung,
who leads the Grain Quality and Structure Research Unit and directs the Hard
Winter Wheat Quality Laboratory at Manhattan.
Food technologist Gary Hareland and physical science technician Dehdra Puhr
evaluate the quality of test bread loaves made with a blend of durum and spring
"We know firsthand the environmental factors influencing this class of
wheat. The same varieties grown in different environments may vary greatly.
About 60 percent of the variations in wheat quality are caused by environmental
For Cakes and CookiesSoft Red Winter Wheat
Future generations will likely benefit from wheat flour improvements made
today by researchers at the Soft Wheat Quality Laboratory in Wooster, Ohio.
"We're working on the wheat flour that will be used in your wedding
cakes," says ARS food technologist Charles S. Gaines to young people
touring the laboratory.
He says that because it takes 8 to 14 years to breed a new commercial wheat
variety, and it'll be about that long before these students will begin to
marry. Since 1992, Wooster scientists have been coordinating a worldwide
consortium for mapping the genome of soft red winter wheat varieties, which are
used to make cookies, cakes, pastries, and crackers.
ARS food scientist Patrick L. Finney says that today's mapping technology is
allowing wheat scientists at the Wooster lab to tie all their knowledge about
the functional properties of soft red winter wheat to individual genes.
"We're focused on the practical sidemilling and bakingbut
we're still dealing in genetic engineering, physics, chemistry, biology, and
food technology," says Finney, who directs the Wooster lab.
The number of new wheat variety releases has risen sharply since the 1930s,
or even the 1970s. For the past decade, Wooster researchers have evaluated more
than 8,000 wheat samples a year submitted by about 20 public and a dozen
private breeding organizations.
Researchers are devising tests for more realistic assessments of wheat
condition than the current method of weighing test batches. Gaines found a way
recently to separate shriveled kernels from rain-puffed ones. Both lower a
grain's test weight and market value. But unlike shriveled kernels, rain-puffed
ones have all the flour that millers expect and are softer than nonpuffed
When breeders are really serious about a variety and close to releasing it,
scientists do the final quality test: They use the flour to bake cookies. The
larger and softer the cookie, the better the wheat.
For Asian Noodles and FlatbreadsSoft White Western
The ARS Western Wheat Quality Laboratory in Pullman, Washington, helps bring
tasty Asian and Middle Eastern dishes to the table. Flatbreads, noodles, and
Japanese sponge cakes, as well as some traditional American cookies and cakes,
are made with soft white wheat grown in the Pacific Northwest.
To better understand milling performance, ARS food technologist Gary Hareland
(right) and North Dakota State University food technician Merle Skunberg
evaluate the quality of semolina from a cultivar of durum that was milled in
the pilot mill.
"Farmers in this region grow all market classes of wheat except soft
red winter," says ARS cereal chemist Craig F. Morris, director of the
Pullman lab. But soft white wheat is predominant. Most of it is exported to
Pakistan and Pacific Rim countries to make dozens of types of flatbreads and
Each year, the lab evaluates up to 7,000 genetically unique samples ranging
from a few tablespoons to 2 bushels each. As at the other wheat quality labs,
Pullman researchers tell how each line or variety performs in milling and
baking trials so breeders can make the best choices.
"Out of 2,000 samples, only 1 or 2 may eventually become commercial
varieties," says Morris.
The Pullman lab is also leading one of the biggest research efforts in North
America on waxy wheat through a cooperative research and development agreement
with a major food company. Waxy wheat contains a natural mutation that prevents
the kernels from making a starch called amylose that is present in other
"Starch from waxy wheat absorbs much more water than normal wheat
starch, stays gooey after heating and cooling, and doesn't lose water when
frozen and thawed," says Morris.
What are these traits good for? "That's what we hope to find out,"
he says. "It's almost like going to the Amazon jungle and bringing back a
new plant species. We've never had this kind of wheat before."
ARS provides the wheat and quality testing, while company researchers look
for ways to use the wheat. Japanese udon noodles already use wheat with a
related mutation, called partially waxy.
For Pizza, PastaHard Red Spring and Durum Wheat
At the ARS Wheat Quality Laboratory at Fargo, North Dakota, researchers
evaluate up to 2,000 hard red spring wheat breeding lines for milling and
baking quality and up to 1,000 durum wheat breeding lines for milling and pasta
quality. Durum wheat is used primarily for pasta and noodles. Hard red spring
wheat is noted for its high gluten content, which accounts for good loaf
Food technologists Charles Gaines (left) and Ron Martin watch as a stream of
air in the large tube separates light, shriveled kernels of soft red winter
wheat from fully filled out, higher density kernels. The amount of flour
produced from the heavier kernels will represent the full genetic flour yield
potential of the wheat.
Food technologist Gary A. Hareland, director of the Fargo lab, explains,
"Gluten imparts flexibility and strength to dough as it rises and helps
maintain structure during baking."
About half of the hard red spring wheat grown in the United States is
exported. Much of the rest is blended with winter wheat flour to improve the
quality of white pan bread. The flour is also used in non-pan breads such as
bagels, pizza crust, and hard rolls.
Durum wheat breeding lines used to make pasta are also rated for firmness
and weight of cooked spaghetti. The scientists are studying ways to measure
spaghetti stickiness, which is unacceptable to consumers.
Durum prices vary more from year to year than prices of other wheats.
"To help even out the price swings," says Hareland, "we're
trying to find another niche for durum besides pasta."
Traditionally, 65 percent of a durum kernel is milled into semolina, a
granular material that is mixed with water and extruded into pasta. Another 10
to 12 percent of the kernel is milled into flour for noodles or, if the quality
is low, into livestock feed. Durum's use in noodles may decline with the advent
of new white winter and spring wheats.
Coming to the rescue are durum breeding lines for dual-purpose bread and
pasta wheat. The feat involves transferring certain glutenin protein genes from
bread wheat to durum wheat.
But even conventional durum flour could find its way into more bread.
Hareland and colleagues have discovered a way to make a good loaf with up to
60 percent durum. Durum flour makes a more flavorful bread with a slightly
nutty taste. Until now, baking qualities of such breads have been poor unless
the flour mix included no more than 25 percent durum.By
Linda Cooke McGraw,
Kathryn Barry Stelljes, and
Ben Hardin, Agricultural
Research Service Information Staff.
This research is part of New Uses, Quality, and Marketability of Plant
Products, an ARS National Program described on the World Wide Web at
Okkyung Kim Chung is at the
USDA-ARS Grain Marketing Research and
Production Center, 1515 College Ave., Manhattan, KS 66502; phone (785)
776-2703, fax (785) 776-2792.
Finney is in the USDA-ARS
Soft Wheat Quality Research Unit, 1680 Madison Ave., Wooster, OH 44691;
phone (330) 263-3890, fax (330) 263-3658.
Craig F. Morris is at the
USDA-ARS Western Wheat
Quality Laboratory, Rm. 209, Johnson Hall, Pullman, WA 99164-6420; phone
(509) 335-4062, fax (509) 335-8573.
Gary A. Hareland is at
Wheat Quality Laboratory, Harris Hall, P.O. Box 5677, Fargo, ND 58105-5677;
phone (701) 239-1340, fax (701) 239-1369.
"Baking Sure New Wheats Measure Up" was published in the
May 1999 issue of Agricultural