Reconstitution baking tests with defatted wheat flour are suitable for determining the functional effects of lipase-treated wheat lipids

Abstract

A microscale reconstitution baking test, using wheat flour defatted with 2-propanol at 20°C, was established to determine the functional effects of lipids isolated from lipase-treated wheat dough. Proper selection of solvent and extraction temperature was of major importance to maintain the functionality of defatted flour. Dough and gluten from flour defatted with water-saturated 1-butanol (WSB; extracted at 20°C) and 2-propanol (extracted at 75°C) had inferior extensibility and loaf volume compared to control flour extracted with 2-propanol at 20°C. Quantitation of gluten proteins showed that defatting with WSB (20°C) or 2-propanol (75°C) decreased the gliadin and increased the glutenin content. Possible reasons were thiol-disulfide interchange reactions, caused either by heat (2-propanol, 75°C) or by the solvent WSB, which affected gluten proteins. Confocal laser scanning microscopy showed that regular, interconnected gluten structures were only present in dough from flour defatted with 2-propanol at 20°C.