Effect of brine solution as a wheat conditioner, on lipase, amylase, and lipoxygenase activities in flour and its corresponding dough rheological properties

Abstract

Wheat conditioning plays a key role on the final quality of flour and consequently it dough and bread. Three levels of brine solution (0.5, 1, and 1.5%) were added to wheat and the grains were conditioned for 24 hr at room temperature. Results suggested that lipase activity was decreased significantly in proportion to salt content of the brine, which may have a positive impact on dough quality. Salt had a significant negative effect (p < .05) on amylase activity. A significant increase was evidenced for lipoxygenase activity in all salt percentages. Use of brine solution, while leading to reduced water absorption and degree of dough softening, increases dough development time and dough resistance to extension. The ratio of dough resistance to extension to extensibility increased along with energy during fermentation. The changes indicated that conditioning of wheat by brine solution may improve flour strength and dough ability to keep the gases produced during fermentation. Practical applications Wheat enzymes, for example, amylase, lipase, and lipooxygenase, have been a matter of interest as they may have positive or detrimental effects on the flour color, dough rheological properties, and bread quality particularly its porosity and volume. During conditioning of the grain, most of the enzymes are activated; however, there are reports that their activity might be affected by the presence of salt. This study was performed to monitor possible beneficiary wheat enzymes' activation during conditioning. The information will be useful for millers in terms of color of the flour and bakers who are involved with the dough and its rheological properties.