1. Canada Western Red Spring
(CWRS) Wheat
CWRS is the largest class of wheat grown in western Canada with an
annual average production of about 15 mio t. The availability of three milling grades,
several guaranteed protein content levels, and carefully defined processing characteristics,
give it the flexibility to be exported to over 60 markets annually. Major uses of CWRS are pan bread, hearth bread and as a strong blending
wheat. It also finds use for noodles, pasta and flat breads in some markets.
The strength range among CWRS varieties is kept relatively narrow in
order to maintain uniformity of strength within and between cargoes (Preston et
al., 1988 and 2001). The most widely grown CWRS variety at present (2004) is AC
Barrie. Physical dough properties of Neepawa, AC Barrie and Laura are shown in Tab.
19 to illustrate the range of strength deemed acceptable for CWRS varieties.
Many CWRS target markets use physical dough parameters as
specifications. The variety Neepawa exhibits the minimum physical dough strength
required of CWRS varieties. Varieties with less strength are not suited to markets
that use rigorous long fermentation baking processes. Adequate strength is also
required to satisfy markets that blend high protein CWRS with lower quality
wheat to improve baking quality. Laura is representative of varieties that
exhibit the maximum limit of physical dough strength permitted for CWRS. Cultivars
that are stronger have extended mixing times, making them poorly suited to short
mechanical development baking processes. The three varieties produce bread of
equivalent quality whether baked by a short mechanical development process
similar to that used by many Canadian bakeries, or by a sponge-anddough process,
which has a 4-hour sponge fermentation time. This assures marketing flexibility.
In the case of short process baking, the mixing requirements of all three
varieties are short enough to ensure adequate dough development within the
mixing time constraints for maximum throughput of commercial short process
bakeries.
 |
Tab. 19: Physical dough properties and baking quality of some CWRS
varieties a
|
Other quality attributes required of CWRS varieties are high test
weight, high protein content, resistance to preharvest sprouting (i.e. high Falling
Number) and good milling performance. Milling performance is judged on the
basis of flour yield and flour refinement (ash content and brightness). High
water absorption is also a requirement. High water absorption is associated
with longer bread shelf-life, and also assures bakers a high yield of bread per
unit of flour. Dexter (1993) has reviewed the quality requirements of CWRS in detail.
There are three milling grades of CWRS. No 1 and No 2 CWRS are
routinely marketed at guaranteed protein levels. The most frequent protein guarantee
is 13.5% (13.5% m.b.) because the long-term average protein content of CWRS is
13.6%. Processing characteristics of No 1 CWRS from the 2003 CGC harvest survey
are shown at three protein levels in Tab. 20.
2. Canada Western Amber Durum
(CWAD) Wheat
CWAD is the second largest class of western Canadian wheat, with
average annual production near 5 mio t. Recently the quality model for CWAD
wheat has undergone revision in response to changing market requirements (Dexter
and Marchylo, 2000). As mentioned earlier, the variety Hercules is the
foundation for international acceptance of CWAD wheat. Since then advances in
drying cycles and press technology have improved pasta colour. As a result,
there is more emphasis on pasta colour in many markets. Also, increasing use of
gluten strength measurements such as the SDS sedimentation test, gluten index
and Alveograph has made durum wheat processors more aware of gluten strength,
and has increased the demand for varieties with stronger gluten.
 |
Tab. 20: Quality of No 1 CWRS from the 2003 western Canadian harvest a,b
|
In response to these changing market demands, Canada released several
new CWAD varieties with better colour and stronger gluten than Hercules. In
1999 two varieties with very strong gluten, AC Pathfinder and AC Navigator, were
granted interim registration for test marketing as Extra-Strong (ES) CWAD. AC
Navigator was well accepted, and it now has full registration. AC Navigator is
marketed identity-preserved from other CWAD varieties to take full advantage of
market demand for strong gluten durum, and also to maintain uniform gluten
strength within regular CWAD shipments. The direction of the Canadian durum
wheat breeding programme is apparent from quality data of breeding lines from
the 1999 Amber Durum Wheat C-Test (Tab. 21). Kyle, registered in 1984 and still
accounting for nearly 50% of CWAD production in 2003, is comparable in gluten
strength to Hercules, as measured by sodium dodecyl sulphate (SDS)
sedimentation, gluten index (GI), and Alveograph P/L (APL) and W (AW) values.
AC Avonlea, registered in 1997, has Hercules-type strength, but improved wheat protein content,
and has consistently exhibited superior pasta cooking quality. AC Avonlea also
has improved pasta yellowness as indicated by higher b* values for spaghetti dried
at 70 °C and 90 °C. AC Morse, registered in 1996, and AC Napoleon, registered
in 1999, are typical of the new CWAD quality model that all future CWAD
varieties must meet. AC Napoleon exhibits improved pasta yellowness. AC Morse
and AC Napoleon both exhibit significantly stronger gluten properties than the Hercules
model. Another durum wheat line with improved quality, Strongfield (formerly DT
712), was supported for registration in 2003.
 |
Tab. 21: Quality data for some Canadian amber durum wheat cultivars a,b
|
As seen in Tab. 21, when used on their own, the extra-strength of the
new CWAD and ESCWAD varieties does not seem to offer much of a cooking quality
advantage over less strong varieties. However, an advantage of the extra strength
of AC Pathfinder and AC Navigator is that when they are blended with weak low
protein varieties, gluten strength and pasta texture of the blends are improved
more than when weak low protein varieties are blended with less strong durum
varieties (Dexter et al., 2001).
All CWAD varieties must have high test weight to ensure high semolina
yield. Semolina refinement is equally important – semolina millers must meet
maximum ash and/or minimum brightness specifications, so CWAD varieties must
produce bright semolina with a low ash content. Protein content must be high
because it is the primary factor associated with pasta texture. Not only must
pasta be intensely yellow (high b*), but it must show no evidence of browning
(high L* and low a*) because of the importance of colour in marketing premium pasta.
 |
Tab. 22: Quality of No 1 CWAD and AC Navigator from the 2003 western
Canadian harvest a,b
|
There are four milling grades of CWAD. If requested, the top two
grades of CWAD are marketed on a guaranteed protein content basis. The quality
of both No 1 CWAD and No 1 AC Navigator from the 2003 western Canadian harvest
is shown in Tab. 22. The future direction of the CWAD breeding programme will
be determined by dialogue with users of Canadian durum wheat.
3. Minor Classes of Western
Canadian Wheat
There are six other classes of common wheat in western Canada: Canada
Western Extra Strong (CWES), Canada Western Red Winter (CWRW), Canada Prairie
Spring Red (CPSR), Canada Prairie Spring White (CPSW) and Canada Soft White
Spring (CWSWS). Another hard white spring wheat class was established in 2004, after undergoing successful test marketing. There are two
milling grades for CWES, CPSR and CPSW, but because of relatively small quantities
they are usually exported under the grade designation "No 2 or
better". There are three milling grades for CWRW, CWSWS and CWHW. Typical
quality for 2002 export cargoes for CWES, CWRW, CPSR and CPSW are shown in Tab. 23.
CWSWS has not been exported in significant quantities in recent years.
 |
| Tab. 23: Quality of No 2 CWES, No 2 CWRW, No 2 CPS-R and No 2 CPSW export cargoes a,b,c |
Canada Western Extra Strong
(CWES) Wheat
CWES strong wheat is a hard red spring wheat with extraordinarily
strong gluten. Annual production of CWES averages about 500,000 t, although in
2002 and 2003 production declined, partly due to drought and also due to less
market demand. There are two milling grades of CWES. CWES is intended as a
dough strength "correctional", or blending wheat. The very strong
gluten allows millers to strengthen dough properties by adding relatively small
amounts of CWES flour.
Canada Western Red Winter (CWRW)
Wheat
CWRW is a hard red winter wheat class. Annual production averages less
than half a mio t, but it has been increasing recently. Formerly CWRW was grown
primarily in southern Alberta where rust is less prevalent than in the rest of
western Canada, but production has moved east into Saskatchewan and Manitoba
with the development of varieties with improved rust resistance. A major goal
of the CWRW breeding programme is to increase protein content, which typically
is about 2% less than for CWRW, and increase flour water absorption. CWRW can
be blended with higher protein wheat and milled for high volume pan breads. On
its own it is suited for hearth breads, flat bread and some types of Asian
noodles.
Canada Prairie Spring Red (CPSR)
Wheat
Despite intensive efforts to breed high quality Hard Red Winter for
western Canada, combining sufficient winter hardiness with satisfactory
processing quality has been very difficult. The CPSR class was introduced in
1985 as a hard red spring wheat substitute for hard red winter wheat. CPSR is intended
for markets that require good milling and baking quality but do not require the
high protein content associated with CWRS wheat. CPSR wheat varieties are about
1.5 to 2% lower in intrinsic protein content than CWRS varieties, which makes
CPSR lower in price per t than CWRS. Producers of CPSR are compensated for that
difference by the significantly higher yield potential of CPSR compared to
CWRS.
It takes over ten years from the time a cross is made to the time a
new variety is registered. It is therefore to the credit of Canadian wheat breeders
that in 1996, just eleven years after the CPSR class was launched, AC Crystal,
a CPSR variety with much improved dough strength and better flour water
absorption compared to previous CPSR varieties, was released. AC Crystal has
received very favourable response during subsequent test marketing. Two other
CPSR varieties, PR 5700, registered in 2001, and PR 5701, registered in 2002,
with even stronger dough than Crystal, are undergoing test marketing. They
promise to impart further improvement in milling quality, dough strength and
baking quality for the class. Annual production of CPSR is approximately 1.5
mio t. CPSR is widely used domestically in the Canadian feed industry because
of its high yield. CPSR has proved itself in diverse markets where it has been
used to produce high quality hearth bread, crackers and Asian noodles. Like AC
Crystal, PR 5700 and PR 5701 replace previously released varieties, thereby improving
the quality of the class; the amount exported should increase.
Canada Prairie Spring White (CPSW)
Wheat
The Canada Prairie Spring White (CPSW) wheat class was launched in
1990. The goal of the CPSW breeding programme is to develop a class of hard white spring wheat that will
find acceptance in high quality Asian noodle markets and Middle East flat bread
markets, where white wheat is preferred. As with CPSR, intrinsic protein
content is 1.5 to 2% lower than for CWRS, but producers are compensated for
lower price by higher yields. The quality of the class has been substantially improved
with the registration of AC Vista in 1996, and AC 2000, which was supported for
registration in 2001. However, production is well below half a mio t, and in
decline. The recent development of high quality hard white spring wheat of
higher protein content, which is discussed later, has made the future of the CPSW
class uncertain.
Canada Western Soft White Spring
(CWSWS) Wheat
CWSWS wheat is a lower protein, soft wheat with weak dough properties.
Flour milled from this class is best suited for confectionery products (cookies, cakes and biscuits).
It also has been used for crackers, flat bread, steamed bread and some types of
Asian noodles. Most CWSWS wheat is grown under irrigation to minimize protein content for the domestic confectionery industry. In
recent years production of this class has been less than 10,000 t, making none
available for export.
Canada Western Hard White
(CWHW) Wheat
The newest wheat class in western Canada is CWHW wheat. In February,
2000, BW 263 (now AC Kanata) and BW 264 (now AC Snowbird), hard white spring
wheat lines that have comparable protein content and dough strength to CWRS
wheat, were recommended for interim registration in western Canada for
test marketing.
The Canadian Wheat Board promoted increase of these varieties through
contract programmes, and following successful international test marketing the
CWHW wheat class was formally established in 2004.
 |
Tab. 24: Milling and baking quality of the CWRS variety AC Barrie
compared to the CWHW wheat varieties AC Kanata and AC Snowbirda
|
 |
Tab. 25: Yellow alkaline noodle properties of the CWRS variety AC
Barrie compared to the CWHW wheat varieties AC Kanata and AC Snowbird a
|
Tab. 24 and Tab. 25 show quality data from field trails of AC Kanata
and AC Snowbird, compared to the most widely grown CWRS variety, AC Barrie. The
CWHW cultivars match the milling performance of AC Barrie at traditional
western flour extraction rates. Ambalamaatil et al. (2002) showed that when milled
to high extraction (> 80%) the CWHW cultivars give an increasing flour
colour advantage over CWRS wheat as the flour extraction rate increases.
AC Kanata and AC Snowbird are doubled haploid lines developed from a
cross between the CWRS variety AC Domain and a white seeded derivative of an elite
hard red spring wheat breeding line. Therefore, as might be expected, the CWHW
cultivars exhibit high water absorption, strong, well balanced dough properties
and high loaf volume, similar to CWRS, and are fully interchangeable with CWRS
with, at most, minimal milling and baking adjustments.
In Asian noodle markets CWHW is intended as multi-purpose wheat for
production of high quality bread and noodles, particularly yellow alkaline noodles
which are made from high protein flour. A major advantage of CWHW wheat over
red seed coated wheat like CWRS is much improved yellow alkaline noodle appearance,
as evident from far fewer visible bran specks compared to AC Barrie (Tab. 25). Yellow
alkaline noodle brightness (L*), redness (a*) and yellowness (b*) values are also
excellent. Yellow alkaline noodle texture is equal to or better than CWRS.
Other Abbreviations
70CS = cooking score for spaghetti dried at 70 °C
90CS = cooking score for spaghetti dried at 90 °C
L* = white/black tristimulus colour coordinate (brightness)
a* = red/green tristimulus colour coordinate
b* = blue/yellow tristimulus colour coordinate
APL = Alveograph P/L ratio
AW = Alveograph W value
BU = Brabender units
C-Test = Cooperative Test
DNA = deoxyribonucleic acid
ES = extra strong
FN = Falling Number
GI = Gluten Index
GM = genetically modified
GMO = genetically modified organism
HVK = hard vitreous kernels
IS = intermediate strength.
K = kernel size pieces per 500 g
KVD = kernel visual distinguishability
m.b. = moisture basis
NIRS = near-infrared spectroscopy
RVA = RapidVisco Analyzer
SDS = sodium dodecyl
sulphate
t = metric tons
(tonnes)
VED = variety eligibility declaration
WPR = wheat protein content
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