Methods for Assuring Varietal Purity in Barley

Randal W. Giroux. Canadian Grain Commission, Winnipeg, Manitoba, Canada. Presented at the 1999 Canadian Barley Symposium and reprinted from the Proceedings with permisssion.

Abstract
Barley germplasm has been developed to produce a variety of end-use products. The two major markets for barley (malting and feed) each demand unique quality characteristics and, as such, barley varieties are developed, sold and marketed as either feed or malting barley, The ability of the grain industry to distinguish varieties or cultivars provides a valuable indicator of grain quality and end?use properties. The need for varietal identification (VID) in malting barley has become increasingly significant in the last five years because of increased demands for varietal purity from the malting barley export market and domestic malthouses. Transforming barley into malt is a complex biochemical process and the art of the maltster is to produce a homogeneous product of consistent quality. Since each variety responds to the malting process in a unique way, the presence of multiple varieties in a barley shipment can have significant effects on uniform germination and the production of high quality malt and malt extract. Currently, export and domestic customers demand in excess of 90% varietal purity. To support this specification, a number of rnethods have been developed to quantify the level of varietal purity present in a barley cargo. This survey of VID methods will show that in the rapidly evolving barley industry, some of the visual VID methods have been lost, a number of laboratory approaches continue to support VID, and new DNA-based methods are being developed.
Keywords: Barley germplasm, varietal identification, varietal purity  

Sintesis