The effect of pumpkin cellulose on the redistribution of structural groups in wheat flour dough and bread

Abstract

Taking into account the recommendations of the FAO WHO to increase the proportion of dietary fiber in the diet, pumpkin products are a promising raw material for inclusion in the recipe of products of various industries, and particulary bakery industry. The content of the main nutrients in pumpkin cellulose is much higher than in high-grade wheat flour: protein — 3.7 times (42% and 11.3%, respectively), dietary fiber — 9.1 times (32% and 3.5 %, respectively). The main protein fraction of pumpkin cellulose is globulin, a slightly lower content is glutelin and albumin, and the content of the prolamin fraction is the lowest. About 87.4% of the total amount of pumpkin cellulose protein was extracted using solvent. The infrared spectra of the dough of the control sample after kneading and the sample with the replacement of 5% of wheat flour with pumpkin cellulose are practically the same over the entire wavelength. In the wavelength range of 1700...1790 nm during fermentation, the spectra shifted significantly upwards, compared to the spectra of the samples after kneading, because pumpkin cellulose, due to its higher content of dietary fibers than wheat flour, as well as its higher water absorption and moisture retention capacity, contributes to less dilution of the dough during fermentation. At a wavelength of 2100 nm, the spectra of the control and replacement dough samples after kneading were superimposed and had a spectral index of 0.46. During fermentation, conformational transformations occur in the structure of the protein matrix. There is a delay in the development of the gluten network due to the inclusion of pumpkin cellulose particles in the gluten frame of the dough. In general, the spectra of samples with 15% replacement of wheat flour with pumpkin cellulose have a similar character to the spectra of samples with 5% replacement. Thus, the partial replacement of wheat flour with pumpkin cellulose in the recipe of wheat bread leads to changes in the structural elements of the dough and the structural and mechanical properties of the dough system and bread.