2001 AACC Annual Meeting Charlotte, North Carolina October 14-18, 2001 Charlotte Convention Center

The Rapid Visco Analyzer (RVA), which provides a definitive, systematic fingerprint that embodies the behavioral properties of a starch-containing material, has been studied for differentiating potato genotypes according to end-use quality. As almost all food uses of potato involve heating, quality is heavily dependent on the ability of a potato to maintain desirable texture through a heating process. With cooked potato texture linked to multiple compositional factors (starch, pectic substances, cations, etc.), the objective of this study was to evaluate the RVA as a potential screening tool for predicting potato end-use quality. Two cultivars (Russet Burbank and IdaRose), which represent quality extremes with regard to cooked texture, were characterized using the RVA to identify differences in their pasting behavior. Material representing each cultivar was prepared for RVA analysis by peeling, cubing, and freeze-drying raw tissue, after which the dried tissue was blended to a powder. Pasting properties were determined using a factorial design in which RVA run parameters were varied to identify combinations of run parameters that provided maximal discrimination of the two cultivars. Depending on RVA run conditions utilized, paste peak viscosity, breakdown, final viscosity, and gelatinization time represented possible RVA attributes by which the cultivars were maximally discriminated. Validation of methods has continued using additional cultivars known to possess intermediate textural properties. The RVA appears capable of accounting for the multiple factors that dictate quality.