Colloid JournalColloid JournalКоллоидный журнал0023-29123034-543XThe Russian Academy of Sciences69745010.7868/S3034543X25050019ArticlesСтатьиResearch ArticlePHASE BEHAVIOR OF FISH GELATIN–AGAR AQUEOUS MIXTURESФАЗОВОЕ СОСТОЯНИЕ ВОДНЫХ СМЕСЕЙ РЫБНЫЙ ЖЕЛАТИН–АГАРVoron’koN. G.ВоронькоН. Г.voronkong@mauniver.ruKuzinaT. D.КузинаТ. Д.email@example.comKolotovaD. S.КолотоваД. С.email@example.comKuchinaYu. A.КучинаЮ. А.email@example.comZuevYu. F.ЗуевЮ. Ф.email@example.comDerkachS. R.ДеркачС. Р.email@example.comMurmansk Arctic UniversityМурманский арктический университетKazan Institute of Biochemistry and Biophysics, Federal Research Center "Kazan Scientific Center", Russian Academy of SciencesКазанский институт биохимии и биофизики ФНЦ КазНЦ РАН15092025875VOL 87, NO5 (2025)ТОМ 87, №5 (2025)46948802122025Copyright ©; 2025, Russian Academy of SciencesCopyright ©; 2025, Российская академия наук2025Russian Academy of SciencesРоссийская академия наукhttps://journals.eco-vector.com/0023-2912/article/view/697450

The interaction of fish gelatin and agar in the bulk of the aqueous phase with the formation of supramolecular protein–polysaccharide complexes was studied using spectroscopy (IR Fourier, UV), turbidimetry, quasi-elastic laser light scattering and scanning electron microscopy. The influence of the structure of gelatin (content of amino acid residues), the agar/fish gelatin w/w ratio Z and the medium (pH, ionic strength I) on the boundaries of the regions of stoichiometric and non-stoichiometric complexes formation, the size and ζ-potential of particles and, consequently, the phase behavior of the aqueous mixture (i.e., colloidal solution) of biopolymers was considered. Phase diagrams of aqueous mixtures of fish gelatin and agar were constructed in the coordinates Z – characteristic pH, as well as I – characteristic pH. The regions of different phase behavior of the systems are determined, such as a single-phase solution of non-complexed biopolymers, a dispersion of fish gelatin–agar complexes, the region of the beginning of the separation of coacerates from the dispersion, and the region of complete separation of the coacervate phase and supernatant. It is shown that the formation of fish gelatin–agar complexes affects the microstructure of gels formed during cooling of aqueous mixtures of biopolymers.

Методами спектроскопии (ИК Фурье, УФ), турбидиметрии, квазиупругого лазерного светорассеяния и сканирующей электронной микроскопии исследовано взаимодействие рыбного желатина и агара в объеме водной фазы с образованием супрамолекулярных белок–полисахаридных комплексов. Рассмотрено влияние строения желатина (содержание аминокислотных остатков), массового соотношения агар/рыбный желатин Z и среды (pH, ионная сила I) на границы областей формирования стехиометричных и нестехиометричных комплексов, размер и ζ-потенциал частиц и, следовательно, фазовое состояние водных смесей (коллоидных растворов) биополимеров. Построены фазовые диаграммы водных смесей агара и рыбного желатина в координатах Z — характеристические pH, а также I — характеристические pH. Определены области с различным фазовым состоянием систем: однофазный раствор не связанных в комплекс биополимеров, дисперсия комплексов рыбный желатин–агар, область начала выделения из дисперсии коацерватов, область полного разделения коацерватной фазы и супернатанта. Показано, что формирование комплексов рыбный желатин–агар оказывает воздействие на микроструктуру гелей, образованных при охлаждении водных смесей биополимеров.

fish gelatinagarphase behaviorsupramolecular complexescoaceratesрыбный желатинагарфазовое состояниесупрамолекулярные комплексыкоацерватыThe work was supported by the Russian Science Foundation, project no. 23-64-10020 and performed on the base of the Research Laboratory of Chemistry and Technology of Marine Bioresources (Murmansk Arctic University), which was created with the support of the Ministry of Science and Higher Education of the Russian Federation (FENR-2024-0001, agreement no. 075-03-2024-024/1 of February 15, 2024).Работа выполнена при финансовой поддержке РНФ, проект № 23-64-10020 на базе Научно-исследовательской лаборатории химии и технологии морских биоресурсов (Мурманский арктический университет), созданной при поддержке Министерства науки и высшего образования Российской Федерации (ФЭНР-2024-0001, соглашение № 075-03-2024-024/1 от 15.02.24). Калинина М.А., Вацадзе С.З. 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