143 Wheat - Identification of Varieties by Electrophoresis

Methods Type: Generic Methods
Key data
Number: 143
Analyte: Identification of Varieties by Electrophoresis
Matrix: Wheat
Year of Approval: 1995
Scope: This International Standard specifies a method for the identification of the variety of a given lot of soft or hard wheat, in the form of individual ground kernels, flour, farina or semolina, by the separation of gliadin proteins.
Principle: The separation of gliadin wheat protein by polyacrylamide gel electrophoresis (PAGE) into 1,5 mm thick slab gels containing aluminium lactate buffer pH 3.1.

Definition

The protein composition of wheat results from direct genetic control and in general is not affected by environmental conditions (e.g. location of year of growth). In addition, because wheat is essentially a self-pollinating plant, the protein composition of the different varieties of wheat remains stable for several plant generations. Therefore, the protein composition of a wheat can be used to characterize and thus to identify its variety.

Protein profiles can be obtained by carrying out polyacrylamide gel electrophoresis (PAGE) separations of the wheat gliadins. The polyacrylamide gels are stained to make the separated protein components visible. If such protein profiles are established for all wheat varieties which can be expected to occur in a particular region (i.e. a variety catalogue is prepared), the identification of an unknown variety of wheat can be established by reference to such a catalogue. Such a practice has been thoroughly characterized and is in common use in numerous countries.

 

Download the complete Standard Method immediately after purchase!