Introduction. Partial enzyme hydrolysis of proteins is common method of modification of their functional properties. The characteristics of partially hydrolyzed proteins obtained from sunflower meal are presented in this work.Materials and methods. Proteins of sunflower meal were extracted in the presence of two proteases viz. neutral protease and Alkalase during 40 min. Partially hydrolyzed protein samples were prepared by isoelectric precipitation and next drying. The polypeptide composition of protein isolates were studied by polyacrylamide gel electrophoresis, degree of protein hydrolysis, amino acid composition, surface activity and functional properties were estimated.Results and discussion. The polypeptides of higher molecular weight (45-54 and about 32-35 kDa) were absent in polypeptide profile of partially hydrolyzed proteins either of proteases. At the same time they were abounded with 14-16 kDa polypeptides and polypeptides with molecular weight lower 14 kDa.Partially hydrolyzed protein samples had higher protein content, lower content of ash and carbohydrates as compared with the control sample. The biological value of sunflower protein isolates were limited by three amino acids -sulfur containing amino acids (methionine and cysteine) and lysine. The content of methionine, cysteine and lysine has been increased in protein samples obtained with neutral protease, relative to protein isolate. Differential scanning calorimetric analyze of protein samples have demonstrated that partially hydrolyzed samples contained undenaturated proteins, but their denaturation degree was higher compared with control samples. Partial hydrolysis of sunflower seed proteins have improved their solubility in pH range from 2 to 8, water holding, oil binding, foaming, emulsifying capacities and surface activity.Conclusions. Partially hydrolyzed protein samples had higher protein content, lighter color, lower degree of denaturation and better functional properties compared to the traditional protein isolates.

In this paper, the processes of cobalt absorption by soils of Ukraine are investigated by using the electrochemical method of pulsed inversion chronopotentiometry. It has been established that the absorption capacity of cobalt by soil varieties from complexing media is 64–98 %. In solutions of KNO3, NH4OH and CSN2H4 mobile compounds of cobalt are part of [Co(H2O)n]2+, [Co(NH3)n]2+,[Co(CSN2H4)n]2+, and in solutions of Na4P2O7, Na5P3O10 and ЕДТА4– anionic complexes [Co(P2O7)n]2–4n, [Co(P3O10)n]2–5n ³ [CoЕДТА]2– are formed. The cobalt cationic complexes [Co(H2O)n]2+, [Co(NH3)n]2+, [Co(CSN2H4)n]2+ are almost completely absorbed by the soils. Anionic complexes – [Co(P2O7) n] 2–4n, [Co(P3O10) n]2–5n ³ [CoЕДТА]2– largely remain mobile in the soil profile. The sorption effect depends on the charge of the complex ions, their strength and on the steriîìåtric parameters of the complex ions. A close positive relationship was established between the cobalt absorption by soils and the cation exchange capacity of soils, the correlation coefficient was 0,7976, and between the cobalt absorption by soils and the humus content (0,7034). In the study of biohumus, it was found that cobalt goes into the solution of 0,02M ЕДТАNa2 + 0,09M NH4Cl by the mechanism of competitive complexation, its transition to the HCl solution occurs due to the protonization of the functional groups of biohumus with which the metal is bound. Biohumus has rather high sorption properties of cobalt and may be promising for its use as an effective carrier matrix in various combinations with basic fertilizers. Isotherms of sorption or exchange of cobalt for exchange ions of biohumus in various solutions correspond to isotherms of Langmuir single layer adsorption. The method of IIHP analysis is important to use to control the content of trace elements at the level of their trace concentrations necessary for plant development.

Introduction. The possibility of using NIR spectroscopy to determine oleic acid in sunflower seeds has not been studied, so research on this field is perspective.Materials and methods. The spectra of seed samples of various sunflower varieties with a known content of oleic acid and the same samples additionally enriched with oleic acid were investigated by NIR diffusion reflectance spectroscopy with using the instrument "Infrapid-61". To process the results obtained, the methods of mathematical analysis were applied.Results and Discussion. In the NIR spectra of samples of dried sunflower seeds, in comparison with the spectra of raw seeds, the expected decrease in the coefficient of diffuse reflection is observed in the range 1920-1940 nm related to the moisture content in the sample. Analysis of NIR spectra of a calibration series of dried seeds enriched with oleic acid shows an increase in the coefficient of diffuse reflection in the wavelength ranges 1920-1940 nm and 2140-2160 nm in proportion to the growth of the mass portion of oleic acid. Corresponding calculations, calibration curves and the obtained equation describing the dependence demonstrate a linear dependence of the reflection coefficient on the mass portion of oleic acid in the sample at the wavelength of 2140 nm with a confidence level of 98%. The dependency found can be used for the quantitative determination of oleic acid in a sunflower seed sample of unknown composition. By the magnitude of the coefficient of diffuse reflection of the sunflower seed sample containing unknown amount of oleic acid, its mass portion in the sample can be determined from the graph. The diffuse reflectance spectra of husked and crushed seed samples and corresponding spectra of crushed sunflower seeds with husks containing the same oleate amount are practically identical with the wavelength range 1330-2370 nm. Therefore, this method can be used for the analysis both intact seeds and seeds separated from husks. The express method of diffuse reflection of NIR spectroscopy can be considered as an alternative to chemical methods for determining the quality indicators of fatcontaining raw materials.Conclusions. The method of NIR spectroscopy is perspective for the determining of other fatty carboxylic acids in sunflower seeds.

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