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Документ The influence of rice protein concentrate on the technological process of wheat bread production(2023) Shevchenko, Anastasiia; Litvynchuk (Vorontsova), Svitlana; Koval, OlgaBakery products from wheat flour are low in protein and it is inferior and also absorbed at a low level. To solve this problem sources of complete proteins may be introduced into the formulation of bakery products. But animal proteins can be allergens. An alternative can be concentrates, hydrolysates and isolates of proteins of vegetable origin, particularly, obtained from rice. Microbiological, biochemical and conformational changes in dough and bread from wheat flour were influenced by adding rice protein concentrate. Gas-forming capacity of the dough with rice protein concentrate decreased by 8.3–20.8 % compared to the control sample where there was increase of the dosage. Gas formation occurred less intensively in the dough with rice protein concentrate, because fermentation was delayed due to a decrease in the availability of nutrients. The first peak on the gas formation graph in case of the dough with the addition of 4–8 % rice protein concentrate was seen after 65 minutes, in the control sample it was after 60 minutes. When adding 16 % of the additive, the first peak of gas formation was not clearly defined. The second peak of gas formation for control sample was observed after 150 min and for samples with rice protein concentrate a bit later and it was not clearly defined. Infrared spectra showed that relative reflection coefficient of samples with rice protein concentrate was lower both for dough after kneading and after fermentation. The addition of 4 and 8 % rice protein concentrate did not affect the amount of formed sugars, and the addition of 16 % reduced this indicator by 1.6 %. The amount of fermented sugars decreased by 3.0–7.8 %. So, changes during the technological process of bread-making can be followed due to the obtained results for obtaining bread with high protein content.Документ Influence of pumpkin cellulose on conformational transformations in dough and bread from wheat flour(2023) Shevchenko, Anastasiia; Litvynchuk (Vorontsova), Svitlana; Drobot, Vira; Shevchenko, OleksandrThe aim of the present study was to determine the effect of pumpkin cellulose addition to wheat flour on conformational transformations in the structure of dough and bread. The granulometric composition, functional and technological properties, and amino acid composition of pumpkin cellulose were compared with those of premium grade wheat flour. The influence of pumpkin cellulose in combination with phospholipids on conformational transformations in the structure of dough and bread was studied by method of infrared spectroscopy in the range of near-infrared regions. It was found that 96% of the particles of wheat flour of the premium grade passed through a sieve with holes of 132 microns, the remaining 4% – through a sieve with holes of 260 microns. Pumpkin cellulose was much coarser, because all 100% of its particles remained on a sieve (hole size 670 microns). Moisture binding capacity of pumpkin cellulose was 3.6 times higher, and moisture retaining capacity was 2.8 times higher than of wheat flour due to the presence of a significant amount of fibers. The amino acid score of lysine (the limiting amino acid in wheat flour) was 0.44. The amino acid score of methionine (the limiting amino acid in pumpkin cellulose) was 3.16, and the amino acid score of lysine was much higher than in wheat flour 3.49. Partial replacement of wheat flour with pumpkin cellulose (5–15%) increased this indicator for lysine by 6.5–15.2%. It was found that infrared spectra of dough samples after kneading (control sample and sample with the partially flour replacement by pumpkin cellulose) practically overlapped throughout the range of wavelengths. During the fermentation process conformational changes of functional groups occurred intensively as well as changes in structural and mechanical properties. The dough ball of the control sample thinned faster. Shape-retaining ability improved with increasing replacement percentage of wheat flour with pumpkin cellulose. The partial replacement of wheat flour with pumpkin cellulose enhanced the biological value of bread and changed the structural and mechanical properties improving shape-retaining ability of dough but decreasing dimensional stability of bread.Документ Identification of beeswax and its falsification by the method of infrared spectroscopy(2018) Vyshniak, Volodymyr; Dimitriev, Oleg; Litvynchuk (Vorontsova), Svitlana; Dombrovskiy, ValeriyInfrared reflection spectra from smooth surfaces of samples (paraffin, ceresin, wax, a mixture of beeswax and ceresin, a mixture of wax paraffin and ceresin, a mixture of wax and paraffin) have a similar structure. There are two clearly expressed maxima at wavelengths of 1510 and 1581 nm. The ratio Rw(1581)/Rw(1510) varies from 1.115 to 1.265. The smallest value corresponds to natural beeswax, and the maximum value is ceresin. After shredding the sample, the infrared spectral diffuse reflections did not undergo significant changes, the most intense spectral maxima did not change its position, but the redistribution of spectral lines by intensity was happened out. There were pronounced differences in the region from 1723 to 2400 nm. The coefficient for the reflection spectra from the smooth surface was ~ 1.2, and for the reflection spectra from the crushed samples ~ 1.1. The reflection spectra in the region from 1100 to 1350 nm have a clear maximum at a wavelength of 1212.5 nm. IR reflection spectra allowed us to clarify the difference between the natural beeswax and ceresin through the ratio of reflection features at 1510 and 1581 nm: the maximal ratio corresponded to the former, while the smallest one to the latter. The different proportion of bands corresponding to CH2 and CH3 stretching vibrations suggested that hydrocarbon chains of wax molecules are longer than those of paraffin and ceresin studied. It was found that hydrocarbon contaminants in the bee wax are associated with narrowing of the C=O band at ~1736 cm-1. The detected spectral laws will enable the identification of natural beeswax and detect its counterfeit.