Structural and Functional Characteristics of Flour and Dough Pentosans of Winter Rye Varieties
The purpose of the work was to compare the technological properties of wholegrain flour and dough stipulated by the quantitative and qualitative composition of arabinoxylans in modern varieties of winter rye using different evaluation methods. Experiments to study the viscosity properties of pentosans of water-meal suspensions and the rheological properties of dough were conducted on 10 varieties of rye bred in Russia. Field experiments were performed in 2016-2018 in Laishevsky district ofthe Republic ofTatarstan. New methods for indirect estimates of the viscous properties of arabinoxylans through swelling ability and water absorption capacity were searched using an amylograph and a pharynograph from Brabender. Parcha variety was characterized by a very high gelatination temperature (more than 73 C) in combination with a high amylogram height. The maximum amylogram height in the experiment (750 a.u.) was found in Populatsiya 17. Ogonyok and Podarok varieties were characterized by the lowest content of the water-soluble fraction of pentosans (1.55% and 1.53%), aqueous extract viscosity (16.3 cSt and 17.2 cSt) and the highest swelling rate (5.7 a.u./min and 5.75 a.u./min). Intervarietal variability in terms of the indicators recorded on the swelling graphs was significant. Swelling test made it possible to evaluate and select valuable breeding material of winter rye for the intended use. The studied rye varieties differed only in the dough stability and quality assessment using farinograph. The best structural and mechanical properties of the dough were noted in Zilant variety. Dough stability was 4.8 min; quality according to the farinograph was 60.5 mm. The viscosity index of an aqueous extract of rye meal is an effective indirect test to quantify the content of arabinoxylans for breeding purposes. A strong positive correlation was established between the value of this indicator and the maximum swelling (r = 0.94), gelatinization peak temperature (r = 0.72), and the falling number (r = 0.82).