Influences de l'ajout de glucose oxydase et de lipase sur l'évolution de la consistance et de la consommation d'oxygène de la pâte de farine de blé tendre au cours du pétrissage

Abstract

Effects of glucose oxidase or lipase addition on dough consistency and oxygen consumption during mixing of unyeasted flour dough.Addition of glucose oxidase enhances dough oxygen consumption and promotes transient peaks of consistency. The delay of apparition of these peaks is shortened with increasing amounts of glucose oxidase added, with the amount of glucose added and with the peroxidase activity. Conversely, the delay of apparition of these peaks increases with increasing amounts of free ferulic acid added to the flour and when catalase activity is added to the dough. Results are discussed by hypothesizing that the glucose oxidase activity in the dough produces hydrogen peroxide and enhances peroxidase activity. This latter enzyme would catalyse macromolecular cross-linking by phenolic linkages. Addition of exogenous lipase promotes both dough consistency and dough oxygen consumption during mixing. Results are in agreement with the fact that lipase activity in the dough increases the polyunsaturated free fatty acid concentration, enhancing the flour endogenous lipoxygenase activity.

Oxidation of Ferulic Acid or Arabinose-Esterified Ferulic Acid by Wheat Germ Peroxidase

“…It was fixed at +0.90 V for the quantification of EFA. The potential of the second working electrode used for the quantification of CSH and H2O2 was fixed in oxidation mode at +1.02 V. The detector response was verified by injection of pure standard solutions containing AA, CSH, H2O2, FA, and EFA (30,20,50,20, and 30 µM, respectively) every four samples in order to overcome electrode passivation.…”

“…This enzyme catalyzes the oxidation of glucose in the presence of molecular oxygen and produces H 2 O 2 (). During breadmaking, GOX supplementation led to changes in the structural properties of the dough affecting its consistency and enhancing the bread volume ( − ). The improving effect of the addition of GOX to wheat flour can be explained by activation of endogenous POD by the H 2 O 2 produced, which could lead to the oxidation of the protein SH into disulfide bridges and/or the gelative oxidation of pentosans.…”

Influence of Shaping and Orientation of Structures on Rheological Properties of Wheat Flour Dough Measured in Dynamic Shear and in Biaxial Extension

“…Glucose oxidase (GOX) of Aspergillus niger has been allowed in the bakery industry since 1997. During breadmaking, GOX supplementation in breadmaking leads to structural and rheological changes in dough such as increased consistency, bread volume enhancement, and crumb homogeneity improvement (Martinez-Anaya and Jimenez 1998; Vemulapalli et al 1998;Ameille et al 2000;Qi Si and Drost Lustenberger 2002).…”