Dr. K. Peter Pauls, University of Guelph

Proteins have an enormous range of functional and structural properties that can be exploited for industrial applications including for the production of films that provide barriers to gases, UV light, moisture and bacteria and could be used in food packaging, paper coatings and in bandaging materials. Protein fractions from wheat can vary considerably and, in the same way that these differences influence flour utility for bread or pasta making, one can anticipate that wheat extracts from different wheat varieties will be more or less suited for film manufacture.
The current research was initiated to characterize the utility of proteins extracted from different varieties of wheat for the manufacture of industrial films. To achieve the overall goal we have:

1. Initiated a detailed analysis of the protein composition of wheat varieties grown in Ontario,
2. Developed methods for extracting the whole protein isolate that preserves its functionality,
3. Developed methods for isolating specific protein fractions from wheat,
4. Developed methods for producing films from the extracts,
5. Begun to test the functional properties of the films.

In the first year of the project we completed an evaluation of the protein quantity and quality of major milling and feed wheat varieties used in Ontario, including four soft wheat varieties and eight hard wheat varieties.

Analysis of the protein compositions for the different wheat varieties was performed. Wheat varieties with different protein compositions were chosen to develop processes for film preparation from the protein extracts and begin to investigate the physical properties of the films. Whole protein films from hard wheat had higher tensile strength and longer elongation before breaking compared to soft wheat protein films.

Methods for isolating specific protein fractions were developed and the physical properties of the fractions were tested. The results suggest that specialized wheat varieties targeted to industrial by-product uses can be developed. The outcomes of this project will provide directions for plant breeding programs about the characteristics that make varieties valuable for bio-product manufacture.