Factors
Determining Wheat Quality Requirements
The definition of wheat quality is diverse because it
varies from region to region, market to market, and company to company. Wheat
quality is also continuously evolving in response to changing consumer
preference and changing processing technology. Globalization impacts on wheat
quality requirements because multi-national companies apply similar quality
specifications worldwide. Another factor affecting quality requirements is the
influence of other cultures. An example is the emergence, in many countries,of
North American-style fast food chains. Tomake high quality buns, a strong high
protein bakery flour is required. This can open up significant demand for better
quality wheat in markets that have traditionally not been quality conscious. In
many countries, competition from imported wheat products drives wheat quality shifts.
Throughout the world the wheat industry is deregulating.
The collapse of centrally planned economies in eastern Europe caused a general decline
in demand for wheat imports, and lowering of quality standards in some
countries within that region. Elsewhere deregulation has increased demand for
higher quality wheat. Deregulation has had a great impact on wheat quality
requirements in Latin America. Free trade agreements necessitated that state-owned
buying agencies be disbanded. In general those agencies purchased wheat with
minimal consultation with millers, and assigned wheat to millers on a quota
basis. When deregulation occurred millers were faced with true competition.
Millers began purchasing wheat independently and paid more attention to wheat
quality in order to protect their market share.
Wheat processing technology impacts on wheat quality
requirements. An obvious example that affects Canada is the diversity of baking
processes and formulas in markets that import CWRS wheat. CWRS varieties must
perform well in bakeries using short mechanical dough development processes and
those using long fermentation processes.
Processing technology advances that become generally
accepted can influence wheat quality models quickly and dramatically. An
example is the quality model for CWAD (Dexter and Marchylo, 1997). An important
milestone for international acceptance of CWAD quality was the registration of
Hercules in 1969. The gluten strength and pasta colour of Hercules was much
better than for previously released Canadian durum wheat varieties. The quality
of Hercules was a direct response to international demand for durum wheat with
stronger gluten and better colour. The importance of gluten strength in
determining pasta texture became more widely recognized as reliable tests to
determine gluten strength and pasta texture became available. Pasta colour and
appearance became important aesthetic marketing tools for premium pasta because of advances in pastamaking
technology. Continuous extrusion under vacuum reduced yellow pigment loss, and
the use of TeflonTM inserts in dies greatly improved pasta surface
characteristics.
The registration of Hercules coincided with a rapid
increase in CWAD production in Canada due to overwhelming market acceptance.
Durum wheat production in Canada rose from less than 500,000 t in the 1960s to
over two mio t in the 1970s. Over the past five years durum wheat production in
Canada has averaged about 5 mio t. As will be discussed later, the CWAD model
is again undergoing review to ensure it continues to meet the demands of current
durum wheat milling and pastamaking technology.
The Canadian
Wheat Variety Registration Process
Development of improved western Canadian wheat
varieties is closely linked to wheat market development. The process begins
with onsite evaluation of the wheat processing industry in target markets by
experts from the Canadian Wheat Board, Canadian International Grains Institute,
Agriculture and Agri-Foods Canada and the CGC. Dialogue with processors identifies
the strengths and the weaknesses of Canadian wheat. Information is shared with
Canadian wheat breeders to expedite the development of breeding lines with desirable
attributes. In response to market feedback, the quality model for a given wheat
class may be revised, or new classes may be developed in response to market
requirements.
Western Canadian plant breeders are responsible for
the testing of breeding lines up to about the F8 generation9. The
final stage of testing in western Canada is known as the Cooperative Test
(C-Test). Promising lines are grown at numerous locations across western Canada
to reflect the diversity in environment and soil. There are a range of C-Tests
for each class and/or region in western Canada. C-Test quality evaluation is coordinated by the GRL.
Most of the quality testing is performed at the GRL,
although the heavy amount of testing requires some collaboration with other
institutes.
The lines entered in each C-Test are evaluated by the
Wheat, Rye and Triticale Subcommittee of the Prairie Regional Recommending Committee
for Grain (PRRCG). Three teams of experts consider wheat agronomic merit, disease
resistance and processing quality, respectively. Lines must exhibit
satisfactory performance in all three categories for three consecutive years.
All lines being tested for a third year must be supported by all three teams before
they can be considered for registration. If the line is promising, and the breeder
has the support of the PRRCG, he or she can apply to the Variety Registration
Office of the Canadian Food Inspection Agency for registration in western
Canada. Once registered, the variety becomes eligible for the milling grades of
the class of western Canadian wheat for which it qualifies.
There is a similar process for registration of wheat
varieties in eastern Canada. The Eastern Expert Committee on Cereals and Oilseeds
assesses the agronomic, disease resistance and quality merit of wheat lines in eastern
field trials. If a line has support, then the breeder applies for registration
in eastern Canada to the Variety Registration Office of the Canadian Food
Inspection Agency.
If a new wheat variety represents a significant quality
breakthrough, it undergoes extensive test marketing. New quality types or
"special" quality types intended for specific "niche" markets
that do not conform to the quality models of existing western Canadian wheat classes
may be assigned temporary registration for contract production within the Experimental
class during test marketing. In western Canada the Canadian Wheat Board, in cooperation
with grain handling companies, uses contract growing programmes to expedite seed
increase and to encourage production. Quality is evaluated on a laboratory-scale
at GRL, and on a pilot-scale at the Canadian International Grains Institute.
Small samples are distributed to customers of Canadian wheat for laboratory-scale
testing to obtain initial market feedback. As more wheat becomes available, larger
quantities are shipped to allow pilot-scale commercial testing. If possible, technical
experts from Canada accompany the larger shipments to observe the processing, and
to exchange technical information.
Note :
9 F8 = 8th filial generation, the offspring
of a genetically specified mating. F1 = first filial generation, the off spring
of parents of contrasting genotypes; second filial generation (F2), the
offspring of two F1 individuals; third filial generation (F3), the offspring of
two F2 individuals, etc.
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