Elucidation of the mechanism that forms breadbaking properties of the spelt grain

Abstract

The technology of making dough from spelt flour differs from that known for flour of soft wheat in which starch grains are firmly bound to the protein matrix. It has been established that the content of protein in spelt grain varied from 15.0 % to 22.5 % for varieties and from 14.0 % to 19.8 % for lines. The content of gluten does not depend on the origin of varieties and lines. It amounted to 31.6‒44.9 % in the grain of varieties and 29.2‒43.6 % in the grain of lines. Technological properties of grain of introgressive lines are similar to those of grain of interspecies spelt lines. Index of gluten deformation of grain of spelt varieties and lines varied from 97 to 116 points and the fall number varied from 389 to 416 s. The spelt baking properties differ from those of soft wheat since the maximum gas-holding capacity of dough prepared of spelt flour comes after 60‒90 min of fermentation and then rapidly decreases. The highest stability during fermentation had dough prepared of flour of Zoria Ukrainy variety and NSS 6/01 and NAK34/12-2 lines. Volume of the bread baked of prime flour was from 303 to 523 cm3, which corresponded to 1.0‒7.6 points. The corresponding figure for dark flour was from 270 to 470 cm3 depending on spelt variety and line. Its quality was high in all samples: 7.2‒8.4 points or 80‒93 % of the maximum value. The bread baked of flour of Zoria Ukrainy variety and LPP 3132, NAK34/12-2 and TV 1100 lines was of the highest quality. The overall estimate of quality of the bread baked of dark flour was very high (8.3‒9.0 points) while the bread baked of flour of Swedish 1 variety and LPP 3117, LPP 3122/2, P 3, LPP 3132, NAK34/12-2 lines had the highest quality (9.0 points). Glossiness of the bread surface and its overall estimate were influenced by the content of protein in grain. Gluten content affected bread quality somewhat less. Gluten deformation index also affected crust surface, pore size and the overall estimate of bread. The bread baked of flour of Zoria Ukrainy variety and LPP 3132, NAK34/12-2 and TV 1100 lines had the highest overall culinary estimate. Technological properties of grain of 16 spelt varieties and lines have been theoretically substantiated and experimentally confirmed. Differences between quality of the bread baked of prime and dark flour were analyzed. Relevance of the differentiated approach to the technological properties of flour for its production was shown. Based on the study of physical-chemical and organoleptic characteristics of bread, promising possibility of its use in the baking technology has been confirmed for expanding assortment of products and improving their quality.