The objective of the study was to assess the impact of supplementing the gluten free bread with fibre preparations of different origin, added in the form of pastes, on the gluten free dough and on the volume and porosity of bread crumb. To make samples of gluten free bread, special recipes were developed. Their specific composition had to increase the content of proteins and dietary fibres to the values appearing typical for wheat-rye and rye bread. The basic mixture of the recipe (80 %) consisted of wheat, maize, and potato starches, and of maize flour. The rest (20 %) were mixtures of the fibre preparations, soya flour, and guar gum. The soya or lupine fibre, pectin, and inulin were used as the dietary fibre preparations. The fibre preparations (15 %) were mixed with soya flour (4 %) and guar gum (1 %) and, then, hydrated to obtain the consistency of paste. In this form, they were added to the gluten free dough. The rheological measurements of the pastes and dough were performed using a TA.XT plus texture analyser system. The doughs were fermented by applying bakery yeast, during a period of 40 min. The bread was baked at 200 ºC during a 40 min period. The gluten free bread volume was measured according to the recommended bakery standards. The pastes significantly differed in their hardness values depending on the original source of dietary fibre. The paste containing lupine fibre and the inulin added showed the lowest hardness. It was found that the addition of inulin into lupine fibre significantly impacted the rheological properties of the mixture. The stickiness and adhesion values measured confirmed the advantageous impact of the lupine fibre on the rheological properties of gluten free doughs. The dough supplemented with the soya fibre and inulin was assessed as the worst. The most advantageous effect on the gluten free bread volume was achieved when the dough was supplemented with a paste containing the lupine fibre.
gluten free bread, dietary fibre, rheological properties