Anotace:
A promising way to create gluten-free foods based on purposeful use of ingredients with a wide range of technological properties is analyzed. Steps to regulate the structural and mechanical properties of gluten-free dough have been determined. These steps allow to improve the structural-mechanical and organoleptic characteristics of the biscuit semi-finished product, to adjust the nutritional value. To determine the technological effect, we considered the connection between the recipe components and the properties of the dough when forming a foamy structure of gluten-free cupcake products. The influence of the design parameters of the mixer (independent factors xi) on the foaming process (Q) has been determined, that is, determining the productivity magnitude from the changes of three main factors: from the attack angle of the frontal surface of the plate working body α, the distance between the plates (step) t and the rotation frequency of working body n. The stability of the foam formed and the rate of its settling and the role of the liquid phase of the dough during short storage before baking were investigated. The comparative characteristics of the microstructure of wheat flour (WF) and extruded corn flour (ECF) in the ratios are presented: a) WF – 100 wt.%; b) WF: ECF – 80:20 wt.%; c) ECF – 100 wt.%. In the tested mixtures, the moisture-holding capacity increases for the sample containing 20% by weight of extruded corn flour two and a half times, and three times for the sample with extruded flour to 100% by weight. With an increasing proportion of extruded corn flour in the flour mixture, the dough density increases and the optimum value is in the range of 0.444 – 0.446 kg.m-3. The comparative characteristic of the microstructure of the samples is given, which has the appearance of foam with the existing and even distribution of air bubbles which later form the porous structure of the biscuit of the semi-finished product. Thus, the size of the formed bubbles of air with the content of wheat flour and starch have a large difference in diameters, in the sample of biscuit dough using ECF 100 wt.% – almost the same size, and between the channels are formed that promote the equalization of air pressure in the middle of the foam system of biscuit dough. It was found that the use of 20 wt.% and 100 wt.% of corn extruded flour contributes to the formation of a fine porous structure of biscuit dough.