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FACTORS AFFECTING THE STRUCTURE OF PECTINS IN DAIRY SYSTEMS: PROTEIN INTERACTION MECHANISMS DURING ACID COAGULATION Factors Affecting the Structure of Pectins in Dairy Systems: Protein Interaction Mechanisms during Acid Coagulation

Published in Cheese- and buttermaking · Issue 3, 2026 · Pages 71–76 · Rubric: Review article
DOI: https://doi.org/10.21603/2073-4018-2026-3-65 · EDN: BOCXZM
Received: 01.06.2026 Accepted: 04.08.2026 Published: 09.09.2026 Language of publication: RUS
The protein-fat matrix of fermented milk products is instable, manifesting as syneresis, stratification, and deterioration of texture. It requires effective natural stabilizers. However, the mechanisms of interaction between pectins and casein micelles under acid coagulation remain understudied, which limits the development of targeted technological approaches. This article describes the factors that determine the structure formation of pectins in dairy systems, as well as the mechanisms of their interaction with casein during acid coagulation. The research featured citrus and apple pectins, casein micelles, whey proteins, and starter microorganisms of the genera Lactococcus, Streptococcus, and Lactobacillus. It involved scientific publications indexed in Russian Science Citation Index, Scopus, and WoS. The nature of pectin structure formation depends on the pH, the ionic strength of the medium, the charge density of macromolecules, and the ratio of product components. The acid coagulation of casein proceeds through four stages, with the key trigger being the rate of lactic acid accumulation by the starter microflora. Low-esterified pectins at pH below 5.0 are adsorbed on the surface of casein micelles by charged fragments of the polygalacturonate chain. Uncharged regions form sterically stabilizing loops that prevent excessive protein aggregation and syneresis (whey separation). Adding 0.1 % pectin to yogurt increases the firmness to the level of its full-fat equivalent and reduces syneresis by 25 %, without affecting the fermentation process or final acidity. The species composition of the starter determines the pH kinetics, the exopolysaccharide synthesis, the proteolytic activity, and the protein matrix density. The effectiveness of pectins depends on the degree of esterification, pH, and ionic strength. The stabilization is achieved through electrostatic adsorption and steric effect while pectin acts as a prebiotic and plasticizer. Research prospects include finding optimal combinations of pectin type and starter composition to produce foods with desired rheological characteristics.
pectin, casein, acid coagulation, structure formation, syneresis, starter microflora, milk curd
Funding
The study was conducted as part of the implementation of the state assignment FNSS-2025-0003.
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1. Tromp, R. H. On the mechanism of stabilisation of acidified milk drinks by pectin / R. H. Tromp [et al.] // Food Hydrocolloids. 2004. Vol. 18(4). P. 565–572. https://doi.org/10.1016/j.foodhyd.2003.09.005

2. Stephen, A. M. Food Polysaccharides and Their Applications / A. M. Stephen, G. O. Phillips, P. A. Williams. – Boca Raton: CRC Press, Taylor & Francis Group, 2006. – 752 p. https://doi.org/10.1201/9781420015164

3. Doublier, J. L. Protein–polysaccharide interactions / J. L. Doublier [et al.] // Current Opinion in Colloid & Interface Science. 2000. Vol. 5(3–4). P. 202–214. https://doi.org/10.1016/S1359-0294(00)00054-6

4. Khubber, S. Low-methoxyl pectin stabilizes low-fat set yoghurt and improves their physicochemical properties, rheology, microstructure and sensory liking / S. Khubber [et al.] // Food Hydrocolloids. 2021. Vol. 111. Art. no. 106240. https://doi.org/10.1016/j.foodhyd.2020.106240

5. Zobkova, Z. S. Faktory povysheniya effektivnosti koagulyacii belkov moloka / Z. S. Zobkova [i dr.] // Molochnaya promyshlennost'. 2016. № 3. S. 39–41. https://elibrary.ru/vmbqqx

6. Matia-Merino, L. Acid-induced gelation of milk protein concentrates with added pectin: Effect of casein micelle dissociation / L. Matia-Merino, H. Singh // Food Hydrocolloids. 2007. Vol. 21(5–6). P. 765–775. https://doi.org/10.1016/j.foodhyd.2006.12.007

7. Gao, F. The effect of degree of esterification of pectin on the grainy properties of post-heated fermented milk / F. Gao [et al.] // Food Hydrocolloids. 2025. Vol. 168. Art. no. 111484. https://doi.org/10.1016/j.foodhyd.2025.111484

8. Hill, C. The International Scientific Association for Probiotics and Prebiotics consensus statement on the scope and appropriate use of the term probiotic / C. Hill [et al.] // Nature Reviews Gastroenterology & Hepatology. 2014. Vol. 11(8). P. 506–514. https://doi.org/10.1038/nrgastro.2014.66

9. Mende, S. Influence of exopolysaccharides on the structure, texture, stability and sensory properties of yoghurt and related products / S. Mende, H. Rohm, D. Jaros // International Dairy Journal. 2016. Vol. 52. P. 57–71. https://doi.org/10.1016/j.idairyj.2015.08.002

10. Agarkova, E. Yu. Issledovanie polidispersnyh molochnyh sistem s poliglikanami / E. Yu. Agarkova [i dr.] // Pischevaya promyshlennost'. 2026. № 3. S. 122–127. https://doi.org/10.52653/PPI.2026.3.3.024; https://elibrary.ru/jlzojq

11. Zhang, H. Preparation of liquid yogurt in the presence of pectin and its formation mechanism / H. Zhang [et al.] // Food Chemistry. 2024. Vol. 452. Art. no. 139473. https://doi.org/10.1016/j.foodchem.2024.139473

12. McClements, D. J. Food emulsions: Principles, practices, and techniques / D. J. McClements. – Boca Raton: CRC Press, 2015. – 714 p.

13. Pham, L. T. H. Enhancing the texture and stability of low-fat yogurt using inulin and durian rind-derived low-methoxyl pectin / L. T. H. Pham, U. P. N. Tran // Chemical Engineering Transactions. 2025. Vol. 122. P. 221–226. https://doi.org/10.3303/CET25122037

14. Agarkov, K. V. Poliglikany kak perspektivnyy komponent kislomolochnyh produktov / K. V. Agarkov [i dr.] // Pischevaya promyshlennost'. 2026. № 4. S. 64–69. https://doi.org/10.52653/PPI.2026.4.4.011; https://elibrary.ru/swpitj

15. Zidi, D. Physicochemical and rheological changes of acidified camel milk added with commercial low methoxyl-pectin / D. Zidi [et al.] // International Journal of Biological Macromolecules. 2019. Vol. 128. P. 347–353. https://doi.org/10.1016/j.ijbiomac.2018.12.244

16. Yang, Y. Passion fruit peel-derived low-methoxyl pectin: De-esterification methods and application as a fat substitute in set yogurt / Y. Yang [et al.] // Carbohydrate Polymers. 2025. Vol. 347. Art. no. 122664. https://doi.org/10.1016/j.carbpol.2024.122664

17. Wusigale. Casein and pectin: Structures, interactions, and applications / Wusigale, L. Liang, Y. Luo // Trends in Food Science & Technology. 2020. Vol. 97. P. 391–403. https://doi.org/10.1016/j.tifs.2020.01.027

18. Kondratenko, V. V. Primenenie pektinov iz razlichnyh bioresursov dlya modifikacii strukturno-mehanicheskih svoystv kislomolochnyh produktov / V. V. Kondratenko, O. B. Fedotova, E. Yu. Agarkova // Molochnaya promyshlennost'. 2024. № 5. S. 15–21. https://doi.org/10.21603/1019-8946-2024-5-4; https://elibrary.ru/ynygsg

19. Semenova, V. A. Sravnitel'naya ocenka svoystv proizvodstvenno cennyh shtammov Lactococcus / V. A. Semenova [i dr.] // Pischevaya promyshlennost'. 2025. № 8. S. 82–87. https://doi.org/10.52653/PPI.2025.8.8.022; https://elibrary.ru/ypieak

20. Sieuwerts, S. Unraveling microbial interactions in food fermentations: from classical to genomics approaches / S. Sieuwerts [et al.] // Applied and Environmental Microbiology. 2008. Vol. 74(16). P. 4997–5007. https://doi.org/10.1128/AEM.00113-08

21. Welman, A. D. Exopolysaccharides from lactic acid bacteria: Perspectives and challenges / A. D. Welman, I. S. Maddox // Trends in Biotechnology. 2003. Vol. 21. P. 269–274. https://doi.org/10.1016/S0167-7799(03)00107-0

22. Salminen, S. Lactic acid bacteria: Microbiological and functional aspects / S. Salminen, A. von Wright. – Boca Raton: CRC Press, 2004. – 629 p. https://doi.org/10.1201/9780824752033

23. Kaledina, M. V. Antipatogennye svoystva zakvasochnoy mikroflory v prisutstvii pektinovyh oligosaharidov / M. V. Kaledina [i dr.] // Molochnaya promyshlennost'. 2023. № 5. S. 66–69. https://doi.org/10.21603/1019-8946-2023-5-5; https://elibrary.ru/httmkt

24. Mobasserfar, R. Grape pomace high-methoxyl pectin: A new prebiotic stabilizer for low-fat synbiotic yogurt gels – Optimization and characterization / R. Mobasserfar [et al.] // International Journal of Biological Macromolecules. 2024. Vol. 282(5). Art. no. 137139. https://doi.org/10.1016/j.ijbiomac.2024.137139

25. Yousefi, M. Recent advances in application of different hydrocolloids in dairy products to improve their techno-functional properties / M. Yousefi, S. M. Jafari // Trends in Food Science & Technology. 2019. Vol. 88. P. 468–483. https://doi.org/10.1016/j.tifs.2019.04.015