Sources of Variation in the Solvent Retention Capacity Test of Wheat Flour

Abstract

The solvent retention capacity (SRC) test uses the ability of flour to retain a range of solvents as a means of evaluating economically important aspects of wheat (Triticum aestivum L.) quality: pentosan content, starch damage, gluten strength, and general water retention. Inbred lines from three soft spring wheat populations (‘Vanna’/‘Penawawa’, ‘Kanto 107’/IDO488, and M2/IDO470) were produced in replicated, irrigated trials in 2000 and 2001 to assess variance components for the SRC tests. Milling yield, flour ash, flour protein, and sugar snap cookie diameter for these genotypes were determined. Flour solvent (water, 500 g kg−1 sucrose, 50 g kg−1 sodium carbonate, and 50 g kg−1 lactic acid) retention capacities were measured, and variances estimated for genotype, genotype × environment interaction, and error terms. The variance of genotypes for SRC values in the three populations ranged from 0.67 to 0.97 of the total variance (genotype, genotype × environment, and error) not attributed to main effects of year and replication. Correlations among genotypes were significant and positive for water, sodium carbonate, and sucrose SRC within all three populations (r = 0.70 to 0.92, P < 0.01). In all three populations, these SRC values were negatively correlated with cookie diameter (r = −0.54 to −0.89, P < 0.01). Correlations between lactic acid SRC, a measure of gluten strength, and the other SRC values were complex, as was the correlation between lactic acid SRC and cookie diameter. This suggests that milling and baking quality could be improved through manipulation of flour components using SRC selection.