Efecto de diferentes alelos de gluteninas de alto peso molecular sobre las propiedades viscoelasticas de la masa de trigos harineros

Abstract

Wheat (Triticum aestivum L.) industrialization quality is intimately related to the quantity and quality of proteins; this depends on the presence of different alleles of glutenin of high molecular weight. To determine the effect of different high molecular weight glutenin alleles on the viscoelastic properties of bread wheat dough, tests were made on a group of 69 lines derived from the cross Rebeca F2000 by Salamanca S75 by single seed descent from F2 to F6, along with the parental varieties. The lines were sown in Roque, State of Guanajuato, México (Fall-Winter 2003-2004) with normal irrigation (five irrigations) and restricted irrigation (three irrigations). The experimental design was randomized complete blocks, and the means were compared with Tukey (p≤0.05). The viscoelastic properties of the dough were evaluated with the variables kneading time (min), mixographic type, alveogramW, alveogram-P/L and alveogram-P/G. The combinations 1−17+18−5+10, 2*−7+8−5+10 and 1−7+8−5+10 presented the best viscoelastic properties of the flour. In genome A, subunit 1 was characterized by inducing greater kneading time and mixographic type. In genome B, subunits 17+18 and 7+8 had a positive effect on the viscoelastic properties of the dough. In genome D, subunit 5+10 was associated with a positive effect on the viscoelastic properties, while subunit 2+12 was associated with a negative effect. When comparing the combinations, it was found that the effect of substituting 5+10 with 2+12 was very marked, given that where the allele 5+10 appeared, high values were found for alveogramW, alveogram-P/L and alveogram-P/G, which increased the strength and tenacity, whereas the extensibility of the dough was reduced. In contrast, when subunit 2+12 appeared, strength was reduced, but extensibility increased, perhaps due to a pleiotropic effect of the genes that control subunits 5+10 and 2+12.