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									Effects of Gluten Composition and
Molecular Weight Distribution on the
Noodle Making Potential of Hard
White Wheats

     Caryn Ong
     Bioresource Research
     (Biotechnology)

     Dr. Andrew Ross
     Dr. Jae Ohm
     Crop and Soil Science/Food Science and Technology, OSU
  The task
Breeding of hard white wheat (HWW) varieties is
targeted at developing wheats with both good
breadmaking and good noodlemaking properties.

The overall aim is to increase our knowledge about
the optimum gluten protein composition to satisfy this
dual-purpose requirement.
Specific Objectives

-   Determine effect of individual protein
    components of gluten on the texture of Asian
    noodles

-   Determine if gluten protein molecular weight
    distributions are predictive of noodle texture

-   Compare abilities of gluten protein molecular
    weight distributions, presence of specific
    protein components of gluten and mixograph
    data to predict noodle texture.
Justification

-   Around 600 million metric tons (mmt) of wheat
    produced worldwide annually (2002)

-   Around 400 mmt used for human food
        - Bread, pasta, noodle

-   Wheat is most valuable cereal crop in Oregon
-   We need to retain and expand export market
    share
     - Asian noodle market is vital
Justification
Asian Noodles

Asian noodles made up of:
     - Flour from common wheat (Triticum
       aestivum)
     - Water
     - Table salt
     - or Alkaline salts
           - e.g. Sodium or potassium carbonates
           - Alkaline noodles are yellower, often firmer and
             have unique flavor and aroma compared to
             just salted noodles
Noodle quality traits

Texture
  -   Firmness
        - Optimum firmness is regional and type
          specific
  -   Springiness, elasticity, smoothness
Color
  -   Brightness
  -   Yellowness / whiteness
Factors that affect noodle
texture:

 - Protein
    - content
       - higher protein content gives firmer
         noodles
    - composition
 - Starch
    - starch composition
        - amylose:amylopectin ratio
    Materials



-   35 elite HWW breeding lines from OSU

-   2 replications at 2 sites
     - Corvallis (Western Oregon)
         - High rainfall, leaf disease pressure
     - Arlington (Eastern Oregon)
         - Low rainfall, deeper soils, drought stress
Wheat proteins

Wheat endosperm proteins are made up of many
component proteins

4 major categories of wheat protein based on
solubility
    -   Glutenin
    -   Gliadin
    -   Albumin
    -   Globulin

Within each category are many different individual
proteins
Separation of GLUTENIN into component proteins on SDS-PAGE
    Gluten

    - Gluten is made up of:
      -   primarily glutenins and gliadins (~80%)
      -   starch, lipid and fiber are minor components

    - Gluten is formed when water and
      mechanical energy (as mixing or sheeting)
      is added to the flour

-    Gluten gives dough its visco-elasticity and
     provides texture to end products
Glutenins


-   Storage proteins in endosperm
     - exist as high and low MW types


-   Functional proteins that provide the elastic
    component of dough visco-elasticity
     - Gliadins contribute the viscous component
    Glutenin Genetics
Wheat is hexaploid and contains
three related genomes: A, B, & D
each with 7 pairs of chromosomes
numbered 1-7

HMW-GS encoded at Glu-1 loci of
 chromosomes 1A, 1B and 1D
    - Glu-1A, Glu-1B, Glu-1D

Each locus has multiple alleles
    - Alleles not genetically linked
    - Any combinations possible
Glutenin Genetics

-   Some combinations of HMW-GS are
    associated with stronger dough and
    better breadmaking quality

-   Specific sub-unit effects in noodles
    not known
     Glutenin Nomenclature
     -   Numbering system developed by Payne
         and Lawrence

     -   Assigned relative to SDS mobility

                                                   1


2
                                               2*


                                               5
12
Key Techniques

-   SDS PAGE
    -   identify high molecular weight glutenin subunits
-   Size Exclusion HPLC
    -   Determine molecular weight distribution
-   Protein Content
    -   Quantity analysis
-   Mixograph
    -   recording dough mixer
-   Noodle Textural Analysis
    -   Physical parameters
            Result

                 SDS PAGE of HMW-GS

Cajeme 71     Moro
Result
Variety   1A      1B          1D
  2        1      7+9        5+10
  1       2*      7+9        2+12
  14      n       7+9        5+10
  5       2*      6+8        2+12
  4       2*       7         2+12
  3       2*     13+19       5+10
   7      1    6+8,17+18,7   5+10
  13      n      17+18       5+10
Result
Result
Result
Result
Conclusion

-   Effects of HMW-GS composition on
    dough mixing properties similar to
    available literature
-   Flour protein content has dominant
    affects on cooked noodle hardness
-   Contributions of HMW-GS masked by
    flour protein content
Future Developments

 Rapid Visco Analyzer
    - Characterization of starch pasting
      properties

 Need to account for starch pasting
 properties on cooked noodle texture
 before reaching a final conclusion
 based on collected data
Acknowledgements
HHMI
Oregon Wheat Commission
Dr. Andrew Ross
Dr. Jae B. Ohm
Dr. Kevin Ahern

								
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