Changes of properties of wheat flour dough by combination L-ascorbic acid with reducing or oxidising agents
Pavlína Pečivová *, Vladimír Pavlínek a, Jan Hrabě
Department of Food Technology and Microbiology, Faculty of Technology, Tomas Bata University in Zlín, T.G.Masaryka 275, 762 72 Zlín, Czech Republic
a Polymer Centre, Faculty of Technology, Tomas Bata University in Zlín, T.G.Masaryka 275, 762 72 Zlín, Czech Republic
E-mail: * xpecivovap@seznam.cz
Abstract: Changes of properties of wheat flour doughs with reducing and oxidising agents and their combinations were measured on an oscillatory rheometer. A small addition of L-ascorbic acid (6.0 ×10–2 % w/w) to L-cysteine hydrochloride monohydrate leads to a lower reducing ability of L-cysteine hydrochloride monohydrate and the dough shows higher tenacity and lower extensibility. On the other hand, the same addition of L-ascorbic acid to inactivated dry yeast leads to an increase in the oxidising effect of the dough. L-ascorbic acid (oxidized by oxygen in the dough to dehydroascorbic acid) was found to be the strongest oxidising agent within the agents used while L-threonine was found to be the weakest oxidising agent. The combination of L-ascorbic acid+L-tryptophan had a stronger strengthening influence on the gluten network of wheat flour dough than the combination of L-ascorbic acid+L-threonine. Mainly combinations L-tryptophan and L-threonine with L-ascorbic acid showed interesting and new results.
Keywords: amino acid, dough, extensibility, tenacity
Full paper in Portable Document Format: acs_0097.pdf
Acta Chimica Slovaca, Vol. 4, No. 2, 2011, pp. 108—117