KEFİR GRANÜLÜ EGZOPOLİSAKKARİTİ: KEFİRANIN ÜRETİMİ, ÖZELLİKLERİ VE UYGULAMALARI

Abstract

Kefir, dünya çapında yaygın olarak tüketilen ve sağlığa faydalı özellikleriyle bilinen süt kaynaklı fermente bir içecektir. Kefir taneleri de, kefir üretiminde kullanılan doğal mikrobiyal inokulumlardır ve fermentasyon sürecini yöneten simbiyotik olarak etkileşim halindeki bakteri ve mayalardan oluşan karmaşık bir yapıya sahiptir. Bu taneler ayrıca, olağanüstü reolojik, işlevsel ve terapötik özelliklere sahip çok yönlü bir ekzopolisakkarit olan kefiran içerir. Bu özellikleri sayesinde kefiran, yalnızca gıda endüstrisinde değil, aynı zamanda gıda ambalajlama, sağlık, ilaç ve doku mühendisliği uygulamalarında da giderek artan ilgi gören çok işlevli bir biyopolimer olarak ortaya çıkmaktadır. Umut vadeden potansiyeline rağmen, kefiranın endüstriyel ölçekte üretimi, yüksek üretim maliyetleri ve fermentasyon sırasında pH düşüşünün engelleyici etkileri nedeniyle zorlu olmaya devam etmektedir. Bu derleme, geleneksel fermente süt ürünü kefir ve kefir tanelerinin karma mikrobiyal yapısı tarafından biyosentezlenen bir ekzopolisakkarit olan kefiranın üretimi, biyolojik aktiviteleri ve uygulama alanlarına dair güncel bir genel bakış sunmaktadır. Özellikle gıda ve sağlık uygulamaları için değerli ve umut vadeden bir biyopolimer olan kefiran üretimini optimize etmek ve işlevsel potansiyelinden tam olarak yararlanmak için daha ileri araştırmalara ihtiyaç duyulmaktadır.

Keywords

• Egzopolisakkarit
• fermentasyon
• kefir
• kefir granülü
• kefiran

KEFIR GRAIN EXOPOLYSACCHARIDE: PRODUCTION, PROPERTIES AND APPLICATIONS OF KEFIRAN

Abstract

Kefir is a fermented milk-based beverage that is widely consumed worldwide and is well recognized for its beneficial health properties. Kefir grains also serve as natural microbial inocula used in kefir production and possess a complex structure composed of symbiotically interacting bacteria and yeasts that govern the fermentation process. These grains also contain kefiran, a versatile exopolysaccharide with remarkable rheological, functional, and therapeutic properties. Owing to these characteristics, kefiran has emerged as a multifunctional biopolymer of growing interest not only in the food industry but also in food packaging, healthcare, pharmaceutical, and tissue engineering applications. Despite its promising potential, the industrial-scale production of kefiran remains challenging due to high production costs and the inhibitory effects of pH reduction during fermentation. This review provides a recent overview of the production, biological activities, and application areas of kefiran, an exopolysaccharide biosynthesized by the microbial consortium of kefir grains in the traditional fermented dairy product kefir. As a valuable and promising biopolymer, particularly for food and health related applications, further research is required to optimize kefiran production and fully exploit its functional potential.

Keywords

• Exopolysaccharide
• fermentation
• kefir
• kefir grains
• kefiran

References

1. Alraddadi, F. A. J., Ross, T., Powell, S. M. (2023). Evaluation of the microbial communities in kefir grains and kefir over time. International Dairy Journal 136: 105490, doi: 10.1016/j.idairyj.2022.105490.
2. Azizi, N. F., Kumar, M. R., Yeap, S. K., Abdullah, J. O., Khalid, M., Omar, A. R., &, Alitheen, N. B. (2021). Kefir and its biological activities. Foods 10(6): 1210, doi: 10.3390/foods10061210.
3. Baars, T., van Esch, B., Diks, M., van Ooijen, L., Zhang, Z., Dekker, P., &, Kort, R. (2025). Bacterial diversity, bioactive peptides, and enhanced immunomodulatory effects in raw milk kefir made with defined starter cultures versus backslopping. International Dairy Journal 164: 106202, doi: 10.1016/j.idairyj.2025.106202.
4. Bayram, O. Y. (2025). Integration of rosemary oil (Rosmarinus officinalis L.) into kefir: Phytochemical profiling and functional impacts. Biocatalysis and Agricultural Biotechnology 70: 103855, doi: 10.1016/j.bcab.2025.103855.
5. Ben Taheur, F., Mansour, C., Skhiri, S. S., Chaaban, H., Jridi, M., Fakhfakh, N., Zouari, N. (2024). Kefir mitigates renal damage caused by zearalenone in female Wistar rats by reducing oxidative stress. Toxicon 243: 107743, doi: 10.1016/j.toxicon.2024.107743.
6. Bengoa, A. A., Iraporda, C., Garrote, G. L., Abraham, A. G. (2019). Kefir micro-organisms: Their role in grain assembly and health properties of fermented milk. Journal of Applied Microbiology 126(3): 686-700, doi: 10.1111/jam.14107.
7. Blandón, L. M., Noseda, M. D., Islan, G. A., Castro, G. R., de Melo Pereira, G. V., Thomaz-Soccol, V., & Soccol, C. R. (2018). Optimization of culture conditions for kefiran production in whey: The structural and biocidal properties of the resulting polysaccharide. Bioactive Carbohydrates and Dietary Fibre, 16, 14-21. doi:10.1016/j.bcdf.2018.02.001.
8. Carvalho, A. P. A. de, Conte-Junior, C. A. (2021). Food-derived biopolymer kefiran composites, nanocomposites and nanofibers: Emerging alternatives to food packaging and potentials in nanomedicine. Trends in Food Science and Technology 116: 370-386, doi: 10.1016/j.tifs.2021.07.038.

9. Chen, Z., Li, Q., Li, F., Yin, L., Wang, L., Ye, T., &, Huang, X. (2025). Evolution in a plant matrix: Adaptive reshaping of kefir grains microbiota and function during long-term soymilk culture. Frontiers in Microbiology 16: 1614639, doi: 10.3389/fmicb.2025.1614639.
10. Chen, Z., Shi, J., Yang, X., Nan, B., Liu, Y., Wang, Z. (2015). Chemical and physical characteristics and antioxidant activities of the exopolysaccharide produced by Tibetan kefir grains during milk fermentation. International Dairy Journal 43: 15-21.
11. Correia, S., Gonçalves, C., Oliveira, J. M., Radhouani, H., Reis, R. L. (2022). Impact of Kefiran Exopolysaccharide Extraction on Its Applicability for Tissue Engineering and Regenerative Medicine. Pharmaceutics, 14(8). doi:10.3390/pharmaceutics14081713.
12. Dailin, D. J., Elsayed, E. A., Othman, N. Z., Malek, R., Phin, H. S., Aziz, R., & El Enshasy, H. A. (2016). Bioprocess development for kefiran production by Lactobacillus kefiranofaciens in semi-industrial scale bioreactor. Saudi Journal of Biological Sciences, 23(4), 495-502 doi:10.1016/j.sjbs.2015.06.003.
13. Dailin, D. J., Malek, R. A., Li, T., Arab, H. (2021). Biosynthesis, production and application of kefiran in food industry: A review. Bioscience Research, 18(1), 102-119.
14. de Lima Barros, S. É., de Lima, H. B., Batista, M. A., Cruz, R. A. S., Barcelos, M. P., Silva, G. M., &, da Silva Hage-Melim, L. I. (2024). Antiallergic, antioxidant, anti-inflammatory and immunostimulant potential of kefiran postbiotic: Molecular docking, prediction of pharmacokinetic properties and biological activity. In Progress in hydrogen energy, fuel cells, nano-biotechnology and advanced, bioactive compounds 209-222. Springer, doi: 10.1007/978-3-031-75984-0_8.
15. Du, G., Chang, S., Guo, Q., Yan, X., Chen, H., Yuan, Y., Yue, T. (2022). Adsorption removal of ochratoxin A from milk by Tibetan kefir grains and its mechanism. LWT 169: 114024, doi: 10.1016/j.lwt.2022.114024.
16. Erdogan, F. S., Ozarslan, S., Güzel-Seydim, Z. B., Kök Taş, T. (2019). The effect of kefir produced from natural kefir grains on the intestinal microbial populations and antioxidant capacities of Balb/c mice. Food Research International 115: 408-413, doi: 10.1016/j.foodres.2018.09.067.
17. Evageliou, V. (2020). Shear and extensional rheology of selected polysaccharides. In International Journal of Food Science and Technology, 55(5), 1853-1861. Blackwell Publishing Ltd. doi: 10.1111/ijfs.14545.
18. Exarhopoulos, S., Raphaelides, S. N., Kontominas, M. G. (2018). Flow behavior studies of kefiran systems. Food Hydrocolloids 79: 282-290, doi: 10.1016/j.foodhyd.2017.10.011.
19. Fahri, M. I., Sherlyna, F., & Nurcholis, M. (2023). In Silico Analysis of Protein of Milk, Soybean, and Kefir as Anti-Thrombotic Bioactive Peptide. HAYATI Journal of Biosciences, 30(2), 216-223, doi: 10.4308/hjb.30.2.216-223.
20. Farag, M. A., Jomaa, S. A., Abd El-Wahed, A., El-Seedi, H. R. (2020). The many faces of kefir fermented dairy products: Quality characteristics, flavour chemistry, nutritional value, health benefits, and safety. Nutrients 12(2): 346, doi: 10.3390/nu12020346.
21. Fiorda, F. A., de Melo Pereira, G. V., Thomaz-Soccol, V., Rakshit, S. K., Pagnoncelli, M. G. B., Vandenberghe, L. P. S., Soccol, C. R. (2017). Microbiological, biochemical, and functional aspects of sugary kefir fermentation: A review. Food Microbiology 66: 86-95, doi: 10.1016/j. fm.2017.04.004.
22. Gagliarini, N., Figoli, C. B., Piermaria, J., Bosch, A., Abraham, A. G. (2022). Unraveling molecular interactions in whey protein-kefiran composite films to understand their physicochemical and mechanical properties: Understanding whey protein-kefiran molecular interaction in composite film. Food Bioscience 50: 102012, doi: 10.1016/j.fbio.2022.102012.
23. Gentry, B., Cazón, P., O’Brien, K. (2023). A comprehensive review of the production, beneficial properties, and applications of kefiran, the kefir grain exopolysaccharide. International Dairy Journal 144: 105691, doi: 10.1016/j. idairyj.2023.105691.
24. Gharaghani, M., Mousavi, M., Khodaiyan, F., Yarmand, M. S., Omar-Aziz, M., Hosseini, S. S. (2021). Octenyl succinylation of kefiran: Preparation, characterization and functional properties. International Journal of Biological Macromolecules 166: 1197-1209, doi: 10.1016/j.ijbiomac.2020.11.002.
25. González-Orozco, B. D., García-Cano, I., Jiménez-Flores, R., Alvárez, V. B. (2022). Invited review: Milk kefir microbiota—Direct and indirect antimicrobial effects. Journal of Dairy Science 105(5): 3703-3715, doi: 10.3168/jds.2021-21382.
26. Hasheminya, S. M., Dehghannya, J. (2020). Novel ultrasound-assisted extraction of kefiran biomaterial, a prebiotic exopolysaccharide, and investigation of its physicochemical, antioxidant and antimicrobial properties. Materials Chemistry and Physics 243: 122645, doi: 10.1016/j.matchemphys.2020.122645.
27. Hasheminya, S. M., Mokarram, R. R., Ghanbarzadeh, B., Hamishekar, H., Samadi Kafil, H., Dehghannya, J. (2019). Development and characterization of biocomposite films made from kefiran, carboxymethyl cellulose and Satureja khuzestanica essential oil. Food Chemistry 289: 443-452, doi: 10.1016/j. foodchem.2019.03.076.
28. Ilıkkan, Ö. K., Bağdat, E. Ş. (2021). Comparison of bacterial and fungal biodiversity of Turkish kefir grains with high-throughput metagenomic analysis. LWT 152: 112375, doi: 10.1016/j.lwt.2021.112375.
29. Jiménez-Pérez, C., Roldán-Hernández, L., Cruz-Guerrero, A., Trant, J. F., Alatorre-Santamaría, S. (2023). Insights on the interaction between kefiran and whey proteins using computational analyses. Chemistry Proceedings 14(1): 47, doi: 10.3390/ecsoc-27-16128.
30. La Torre, C., Fazio, A., Caputo, P., Tursi, A., Formoso, P., Cione, E. (2022). Influence of three extraction methods on the physicochemical properties of kefirans isolated from three types of animal milk. Foods 11(8): 1098, doi: 10.3390/foods11081098.
31. La Torre, C., Plastina, P., Abrego-Guandique, D. M., Caputo, P., Rossi, C. O., Saraceno, G. F., & Fazio, A. (2024). Characterization of exopolysaccharides isolated from donkey milk and its biological safety for skincare applications. Polysaccharides 5(3), 493-503, doi: 10.3390/polysaccharides5030031.
32. Marangoni Júnior, L., Vieira, R. P., Anjos, C. A. R. (2020). Kefiran-based films: Fundamental concepts, formulation strategies and properties. Carbohydrate Polymers 246: 116609, doi: 10.1016/j.carbpol.2020.116609.
33. Marques Soutelino, M. E., da Silva Rocha, R., Teixeira Mársico, E., Almeida Esmerino, E., Cristina de Oliveira Silva, A. (2025). Innovative approaches to kefir production, challenges, and current remarks. Current Opinion in Food Science 61: 101252, doi: 10.1016/j.cofs.2024.101252.
34. Maughan, L., Koolman, L., Macori, G., Killian, C., Fanning, S., Whyte, P., Bolton, D. (2025). Characterization of bacterial and fungal populations in retail kefirs in Ireland. Journal of Dairy Science 108(8): 8187-8204, doi: 10.3168/jds.2025-26587.
35. Medrano, M., Cordova, C., Rodriguez, B., Simonelli, N., Olivero, P., Abraham, A. G. (2024). Kefiran in vitro biological activity on enterocytes and mesodermal origin cell lines: Focus on adenocarcinoma cells HT29. Bioactive Carbohydrates and Dietary Fibre 32: 100457, doi: 10.1016/j.bcdf.2024.100457.
36. Medrano, M., Gangoiti, M. V., Simonelli, N., Abraham, A. G. (2020). Kefiran fermentation by human faecal microbiota: Organic acids production and in vitro biological activity. Bioactive Carbohydrates and Dietary Fibre 24: 100229, doi: 10.1016/j.bcdf.2020.100229.
37. Montoille, L., Morales Vicencio, C., Fontalba, D., Ortiz, J. A., Moreno-Serna, V., Peponi, L., Matiacevich, S., Zapata, P. A. (2021). Study of the effect of the addition of plasticizers on the physical properties of biodegradable films based on kefiran for potential application as food packaging. Food Chemistry 360: 129966, doi: 10.1016/j.foodchem.2021.129966.
38. Moradi, Z., Kalanpour, N. (2019). Kefiran, a branched polysaccharide: Preparation, properties and applications: A review. Carbohydrate Polymers 223: 115100, doi: 10.1016/j.carbpol.2019.115100.
39. Moretton, M., Khomenko, I., Cunedioğlu, H., Spano, G. (2025). Comparative volatilome profiling of milk kefir and cereal-based kefir analogues fermented with milk and water kefir grains. Food Bioscience 74: 107731, doi: 10.1016/j. fbio.2025.107731.
40. Oliveira Filho, J. G. de, Duarte, L. G. R., Belo, L., Souza, T. F. C. de, Bitencourt, A. H., Yamim, S. T., Egea, M. B. (2025). Recent advances in kefiran polymer to produce nanofibers and films for food packaging applications. In Food and Humanity 4: 100603, Elsevier B.V., doi: 10.1016/j.foohum.2025.100603. Ondul Koc, E., Inal, M. (2025). Evaluation of rheological and functional properties of kefiran biopolymer isolated from kefir grains. Chiang Mai Journal of Science 52(6):1-14, doi: 10.12982/CMJS.2025.086.
41. Piermaría, J., Bengoechea, C., Abraham, A. G., & Guerrero, A. (2016). Shear and extensional properties of kefiran. Carbohydrate Polymers, 152, 97-104, doi:10.1016/j.carbpol.2016.06.067.
42. Pogačić, T., Šinko, S., Zamberlin, Š., Samaržija, D. (2013). Microbiota of kefir grains. Mljekarstvo 63(1): 3-14.
43. Qiu, Y., Yan, F., Yu, H., Li, H., Xia, S., Zhang, J., Zhu, J. (2024). The protective effects of kefir extract (KE) on intestinal damage in larval zebrafish induced by oxytetracycline: Insights into intestinal function, morphology, and molecular mechanisms. Food Research International 190: 114642, doi: 10.1016/j. foodres.2024.114642.
44. Radhouani, H., Gonçalves, C., Maia, F. R., Oliveira, J. M., & Reis, R. L. (2018). Biological performance of a promising kefiran biopolymer with potential in regenerative medicine applications: A comparative study with hyaluronic acid. Journal of Materials Science: Materials in Medicine 29(8):124, doi: 10.1007/s10856-018-6132-7.
45. Rimada, P. S., Abraham, A. G. (2012). Structural investigation and response surface optimisation for increased kefiran production. Food Chemistry 133: 287-293, doi: 10.1016/j.foodchem.2012.01.034.
46. Sabaghi, M., Maghsoudlou, Y., Habibi, P. (2015). Enhancing structural properties and antioxidant activity of kefiran films by chitosan addition. Food Structure 5: 66-71, doi: 10.1016/j.foostr.2015.06.003.
47. Shahabi-Ghahfarrokhi, I., Khodaiyan, F., Mousavi, M. (2015). Preparation of UV-protective kefiran/nano-ZnO nanocomposites: Physical and mechanical properties. International Journal of Biological Macromolecules 72: 41-46, doi: 10.1016/j.ijbiomac.2014.07.047.
48. Tan, K.-X., Chamundeswari, V. N., Loo, S. C. J. (2020). Prospects of kefiran as a food-derived biopolymer for agri-food and biomedical applications. RSC Advances 10(42): 25339-25351, doi: 10.1039/D0RA02810J.
49. Tanure, Y. C. B., Mafra, A. C. M., Guimarães, B. L. M., Magalhães, R. C., Fagundez, C., Nascimento, I. J. B. do, Brito, J. C. M. (2025). Potential benefits of kefir and its compounds on Alzheimer’s disease: A systematic review. Brain Behavior and Immunity Integrative 10: 100115, doi: 10.1016/j.bbii.2025.100115.
50. Türkmen, N. (2017). Kefir as a functional dairy product. In Dairy in human health and disease across the lifespan: 373-383, Academic Press, doi: 10.1016/B978-0-12-809868-4.00029-7.
51. Walsh, A. M., Crispie, F., Kilcawley, K., O’Sullivan, O., O’Sullivan, M. G., Claesson, M. J., Cotter, P. D. (2016). Microbial succession and flavor production in the fermented dairy beverage kefir. mSystems 1(5): e00052-16, doi: 10.1128/mSystems.00052-16.
52. Wiącek, A. E., Furmaniuk, A. (2024). Starch-based polysaccharide systems with bioactive substances: Physicochemical and wettability characteristics. International Journal of Molecular Sciences 25(9): 4590, doi: 10.3390/ijms25094590.