Studying the effect of milk processing products on the structural-mechanical properties of wheat flour dough

Abstract

Dry whey enriched with magnesium and manganese (DW) that contains protein in the amount of 13 %, and a whey protein concentrate (WPC) with a protein content of 65 %, have been chosen as functional bases in the production of complex baking improvers with a targeted effect. When developing a composition of the complex improver, the rational dosage of DW is 2 % by weight of flour, and that of WPC – 3 % by weight of flour. Adding DW and WPC during the kneading of wheat flour dough predetermines a decrease in its gluten content, by 4 % and 6.1 %, respectively, after 20 minutes of the dough rest, and by 7.5 and 10.7 % after two hours of the dough fermentation. This is due to the introduction of lactic acid with milk processing products, which peptizes proteins resulting in that the gluten proteins are partially converted into water-soluble ones. If DW and WPC are included in the dough formulation, there is an increase in the total amount of proteins in it, as well as a change in their fractional composition: the mass fraction of water-soluble and intermediate fractions of proteins increases while the amount of gluten proteins decreases. That confirms a decrease in the amount of gluten washed out from the dough with the addition of DW and WPC. Increasing the mass fraction of water-soluble proteins contributes to the intensification of the fermentation process through the additional nutrition of microflora with nitrogenous substances and an increase in the content of free water in the dough, which predetermines its thinning. It was established that despite the high water absorption capacity of DW and WPC, the water-absorbing ability of the dough that contains them decreases compared to control by 8.4 and 10.7 %, respectively. Studying the dough at the farinograph has shown that in the case of using DW, its stability is somewhat prolonged while in the case of WPC introduction the dough stability is extended by almost 10 minutes, which leads to prolonging the dough kneading. Along with this, in the case of using WPC, there is a rapid descent of the farinogram curve, which could lead to a strong weakening of the dough during fermentation and rest, even though that the thinning after 12 minutes is lower than that of control