Wheat utilization for the production of starch, gluten and extruded products

Five years ago in San Diego, USA, a Wheat Industry Utilization Conference took place under the direction of Y. Pomeranz who published the presented papers under the title Wheat is Unique.1 The information gathered in that publication still represents today the present state of knowledge on the structure, composition, processing, end-use properties and products of wheat. This is also true of the topics discussed here, the extraction of starch and gluten from wheat and extrusion cooking, on which the present author contributed two conference papers.2,3 Therefore, as only a few new findings can be reported, this chapter will concentrate on presenting the current state of knowledge on these topics with special reference to the functional characteristics of wheat gluten and starch. In so doing, the process technological possibilities for the extraction of starch and gluten from wheat flours and wheat wholemeal flours as well as the application of wheat starch and wheat flours for the manufacture of extrusion cooking products will be emphasized. Special emphasis is also given to the gluten-forming properties of wheat proteins and the two starch fractions present in the endosperm which differ not only in size but also in physical and chemical properties.