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This article considers the effect of protein–starch interaction on the gelling, textural, andsensory properties of keropok lekor used as a fish protein–starch model. A two-level factorial design was employed to analyze the quality and acceptability of different formulations of keropok lekor crackers depending on the ratios of minced fish (MF, 20–50 g (w/w)), sago starch (SS, 10–40 g (w/w)), and water (W, 10–35 g (w/w)). The parameters measured were the onset (T0) and peak (Tp) temperatures of gelatinization, storage modulus (G′), and loss modulus during gelatinization (G″). The samples were rated by a group of 30 panelists during texture profile analysis and sensory evaluation. The most preferred samples had the MF : SS : W ratio of 20 : 10 : 10 and were characterized by the lowest onset and peak temperatures of gelatinization. Therefore, this formulation was singled out as optimal for keropok lekor.

The food industry uses sonochemical treatment as part of emulsification, homogenization, and dispersion, as well as to modify viscosity and structure. Starch is one of the most common food ingredients, both as a raw material or a property-modifying additive. The research objective was to study the effect of sonochemical action on the structural and mechanical properties of wheat starch suspensions. The study involved suspension samples with 10% wheat starch. The suspension samples were treated with ultrasound using an ultrasonic device Volna-M model UZTA-1/22-OM or in an ultrasonic bath (22 kHz; 100, 150, 300, and 400 W). The treatment time was 15 and 30 min. The rheological, physical, and textural properties were recorded according to conventional methods before and after the treatment. The ultrasonic treatment caused mechanical damage to the starch, making it more accessible to moisture when heated. As a result, the structural, mechanical, and rheological properties of starch suspensions changed. All the studied suspensions had a non-Newtonian character. The ultrasonic treatment increased their consistency coefficient from 28.12 to 152.75 µPa·s. The gelatinization temperature of all experimental starch suspensions dropped from 63.4 to 61.0°C. The short high-power ultrasound treatment reduced the strength of gels to 1.25 N compared to that of native starch gel (4.28 N). In this research, the ultrasound treatment of wheat starch suspensions modified the structural, mechanical, and rheological profile of starch and proved able to replace some conventional starch modification procedures, i.e., chemical, physical, or enzymatic. The new approach can provide modified starches of a preset quality while reducing energy costs and processing time.

Introduction. The main component of quinoa grain is starch, the properties of which affect the quality of quinoa-based food products. There is no information about quinoa starch in the Russian scientific literature. Therefore, the review summarizes and presents foreign knowledge about the isolation, chemical composition, structure, and physicochemical properties of quinoa starch Study objects and methods. The research featured scientific articles and chapters of scientific books on the structure and chemical composition of quinoa published over the past 10 years. The work used empirical and theoretical methods of scientific research. Results and its discussion. Currently, starch from quinoa grain is produced only under laboratory conditions by various methods of grinding and soaking. Most studies point to up to 10% of amylose in quinoa starch. Amylopectin in quinoa starch has a high number of short single chains and a very low number of long single chains, and their ratio is higher than that in other starches. The granule size of quinoa starch is 0.4–2.0 microns, which is significantly smaller than that of most starches. Quinoa starch belongs to polymorphic type A. The gelatinization temperature and enthalpy of quinoa starch are lower than those of amaranth, corn, sorghum, millet, and wheat starch, which is probably due to the fine structure of amylopectin. With an increase in temperature for every 10°C, the swelling force and solubility of quinoa starch increase on average by 21.5–27%. As the temperature rises from 55 to 65°C, the solubility index of quinoa starch increases sharply by 5–10 times. The viscosity of quinoa starch is significantly higher than that of most known starches. It also is more sensitive to enzymes. Conclusion. The work presents the results of scientific research on various matters: methods of starch isolation from quinoa, its chemical composition, and methods of amylose determination; structure of starch grains, their shape, type, and degree of crystallization; physicochemical properties of starch, including gelatinization, swelling, solubility, rheological properties, retrogradation, changes in the transparency of starch gel, and susceptibility to enzymes. The latter determines the choice of technological parameters in the development of formulations and food technologies, including functional foods for people with gluten intolerance (celiac disease). Further studies of the chemical composition of quinoa can help to meet the growing demand for these products and expand the range of the domestic market for gluten-free foods.

The article presents experimental data on the assessment of the rheological properties of dough from new types of flour, formed on the basis of cumulative curves using the Mixolab device. The data of mixolabograms and radial diagrams (Mixolab profiler) made it possible to reveal the existing differences in the parameters of the rheological profile and Mixolab indices. The object of the study is composite mixtures of gluten-free flours: No. 1 is 50% of pumpkin and 50% of corn flour, No. 2 is 50% of linseed and 50% of corn flour, No. 3 – 50% of rice and 50% of corn flour, No. 4 – 75% of linseed and 25% of corn flour, No. 5 is 30% of linseed and 70% of rice flour. The use of composite mixtures is promising due to high oven rise and low starch thickening because of its high water absorption capacity (WAC). In addition, there is certain economic efficiency, since it is possible to produce more dough at a lower cost.