The basic structural element of the cell walls of beet pulp is dietary fibers, therefore deep processing of this type of raw material is of considerable interest. One of the main physicochemical properties of dietary fibers used in food production is their water holding capacity. However, dietary fibers of beet pulp, as heterogeneous polymer components, are extremely labile to the conditions of their extraction. In this regard, it is relevant to identify technological factors and their rational sequence, in which the target properties will be expressed to the maximum extent. The authors developed an extensive algorithm for the sequential extraction of dietary fibers from beet pulp with selective processing by homofermental preparations, including various options for the preliminary preparation of raw materials. As a result, samples of beet fibers (mainly homogluacutronanes), corresponding to the key graph nodes of the developed algorithm, were identified. For each sample, the magnitude of water holding capacity was determined, as well as the Raman spectrum on an excitation wave of 785 nm with a spectrum scan duration of 3 s and 50 passes per spectrum. In the process of research, the key influence of the degree of saturation of the cell wall matrix with polyvalent metal ions was established. At the same time, in the presence of cations in the matrix, the number of fermentation stages of the same type and their duration play a key role in the formation of water-holding capacity. In the absence of cations, water holding capacity depends only on the nature of the polymer fermentation products. By the method of principal components, it was established that the water-holding capacity is closely related to the activity of oxygen atoms of glycosidic bonds between the links of the polymer chain, as well as the activity of hydroxyl groups not belonging to the carbohydrate ring. However, the main components used describe only 53.5% of the peak heights dispersion, which may indicate participation in the formation of peaks and any third-party factors, which indicates the necessity of further research.

food fibers, sugar beet pulp, water-holding capacity, homogalacturonans, nonuronid food fibers, enzymes, homoenzyme substances

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