Lectures 12- Flashcards
Wheat
Wheat (T. aestivum) originated in the Middle East and is one of the oldest domesticated crops grown for human food
Einkorn is a diploid (A)
Emmer and durum are tetraploids (AB)
Bread wheat is a hexaploid (ABD)
Global Wheat Production
4.5 billion people rely on wheat for 20% of their daily calories
World production greater than 700 million tonnes, on over 200 million hectares
Canada ranked 6th in the world with a total production over 24 million tonnes in 2014
Canada is one of the world’s top wheat exporters, and the industry relies on the international market
Over 96% of Canadian wheat is grown in the Prairie provinces
Canadian Wheat Production
Canada’s second most seeded crop (after canola)
Canada’s highest yielding crop (over 1.1 million bushels in 2016 versus 812,000 for canola)
Spring bread wheat accounts for >60% of total Canadian wheat acreage
Over 96% of Canadian wheat is grown in the Prairie provinces
Nine Western wheat milling classes:
Varieties are grouped based on their functional attributes: spring/winter habit, kernel colour, size and shape, embryo size and shape, and quality/baking characteristics
Nine Western wheat milling classes
Canada Western Red Spring (CWRS) Canada Northern Hard Red (CNHR) Canada Western Red Winter (CWRW) Canada Western Extra Strong (CWES) Canada Prairie Spring Red (CPSR) Canada Prairie Spring White (CPSW) Canada Western Amber Durum (CWAD) Canada Western Hard White Spring (CWHWS) Canada Western Soft White Spring (CWSWS)
The Western non-milling class (Canada Western Special Purpose (CWSP))
For wheat that cannot meet the quality requirements, and will have poor end-use
High yielding and low protein
Ethanol and animal feed
Canada Western Hard Red Spring (CWRS)
- Accounts for 81% of bread wheat production across western Canada in 2016
- Hard Red wheat
- Superior baking and milling quality
- Three milling grades
- High protein concentration (~13.7%)
- Flour can be used alone or blended
Wheat Breeding
Modern wheat:
- Shorter stature, reduced lodging, higher grain yield, higher harvest index, more kernels per spike, disease & insect resistance (Austin et al. 1989; Vandeleur and Gill 2004)
Canadian focus;
- Disease resistance, higher quality, increased yield (Walton 1968; McCaig and DePauw 1995)
Historical wheat:
- Older cultivars
- Selected before widespread use of synthetic inputs
- Better suited to low-input systems?
Wheat Types
Growth habit: Spring or winter
Kernel colour: White, red, amber
Kernel texture: hard (vitreous) or soft
Gluten proteins: contain essential amino acids
Glutens
-Wash dough with water, and the sticky yellow-grey material left (after water & starch) = Gluten
80% protein (high glutamine & proline; low lysine) + lipids + minerals
- Gliadin: Alcohol insoluble: Cohesion viscosity
- Glutenin: Alcohol soluble: elastic + strength
Grading Factors for Wheat
- Primary Test Weight (density of sample) Varietal purity Vitreousness (hardness) Soundness Foreign matter (weeds, other crops, disease, stones, etc)
- Secondary
Dockage
Moisture
Protein content
Wheat Quality
Wheat quality aspects of different wheat classes
Wheat quality:
- Protein amount
- Gluten strength
- Hardness
Wheat Soil Zone
Black soil zone:
- High yield
- Low protein
Dark Brown and Brown soil zone:
- Low yield
- High protein
Wheat Protein
- Yield and protein are inter-related:
- Genetic
- Environmental
- Improved yield/maturity:
- Relationship requires a lower protein percentage, biologically
Factors effecting choice of wheat type
Tradition
Availability
Cost
Politics
Physical and chemical properties that effect bread making potential.
Kernel colour – Red, white, amber
Kernel hardness – Flour yield, flour absorption
Protein content – End Product quality
Protein strength (high molecular wt. glutenins/gluten
End product quality
Carrying capacity
Amylase active
