Kefir is a fermented milk product. The kefir grain starter consists of lactic acid bacteria and yeast that produce lactic acid and alcohol. The quality of kefir is strongly influenced by the type of milk used, the amount of kefir grain, kefir grain microorganisms, and the incubation period. The characteristics of goat-milk kefir with the addition of different amounts of kefir grain were studied by measuring pH value, ethanol content, and percentage of lactic acid. The experimental design was a completely randomized design (RCD) with three treatments and five replications. The treatments were performed by using different amounts of kefir grains i.e., 2%, 4%, and 6%. Goat-milk kefir was pasteurized at 105oC for 5 minutes, cooled at room temperature (37oC), and then kefir grain was added at different levels and incubated for 12 hours. The results showed that the amounts of kefir grain had a significant effect (p<0.05) on pH value, the percentage of lactic acid, and ethanol content of goat-milk kefir produced. The higher dose of kefir grain had an influence on physicochemical characteristics, microbiology, and sensory of goat-milk kefir. The optimal characteristics of goat-milk kefir were 2% kefir grain with a pH value of 5.40, lactic acid content of 0.14%, and ethanol content of 0.69%. The weight gain of kefir grain was 7.21% and the total of lactic acid bacteria was 1.64x107 CFU/mL. Sensory quality had a white color, kefir scent, a non-acid taste, and like preference. It is concluded that the best goat-milk kefir can be produced by the addition of 2% kefir grain based on physicochemical, microbiological, and sensory characteristics.
Arslan, S. 2015. A Review: chemical, microbiological and nutrional characteristics of kefir. Cyta-Journal of Food 13:340-345. https://doi.org/10.1080/19476337.2014.981588
Astawan, M., T. Wresdiyanti., Suliantarai., I. I. Arief, & R. Septiawan. 2012. Production of synbiotic yogurt-like using indigenous Lactic Acid Bacteria as functional food. Med. Pet. 35:9-14. https://doi.org/10.5398/medpet.2012.35.1.9
Chen, M. J., J. R. Liu, C. W. Lin, & Y. Y. Tzu. 2005. Study of the microbial and chemical properties of goat milk kefir produced by inoculation with Taiwanese kefir grains. Asian-Australas. J. Anim. Sci. 18:711-715. https://doi.org/10.5713/ajas.2005.711
Codex Allimentarius. 2003. Codex Standard for Fermented Milk (Codex Stand 243-2003) CCNEA document (CA/NEA 13/7/6).
Gao, X. & B. Li. 2016. Chemical and microbiological characteristics of kefir grains and their fermented dairy products: A review. Cogent Food Agric. 2:1272152. https://doi.org/10.1080/23311932.2016.1272152
Garofalo, C., A. Osimani, V. Milanović, L. Aquilanti, F. De Filippis, G. Stellato, S. Di Maura, B. Turchetti, P. Buzzini, D. Ercolini, & F. Clementi. 2015. Bacteria and yeast microbiota in milk kefir grains from different Italian regions. Food Microbiol. 49:123–133. https://doi.org/10.1016/j.fm.2015.01.017
Gulitz, A., J. Stadie, M. Wenning, M. A. Ehrmann, & R. F. Vogel. 2011. The microbial diversity of water kefir. Int. J. Food Microbiol. 151: 284–288. https://doi.org/10.1016/j.ijfoodmicro.2011.09.016
Hassan, F. A. M., H. M. Abbas, A. M. Mona, A. E. Gawad, & A. K. Enab. 2014. Goats dairy products as a potentially functional food. Life Science Journal 11:648-657.
Leite, A. M. O., B. Mayo, C. T. C. C. Rachid, R. S. Peixoto, J. T. Silva, V. M. F Paschoalin, & S. Delgado. 2012. Assessment of the microbial diversity of Brazilian kefir grains by PCRDGGE and pyrosequencing analysis. Food Microbiol. 31:215–221. https://doi.org/10.1016/j.fm.2012.03.011
Leite, A. M. O., D. C. A. Leite, E. M. Del Aguila, T. S. Alvares, R. S. Peixoto, M. A. L. Miguel, J. T. Silva, & V. M. F. Paschoalin. 2013. Microbiological and chemical characteristics of Brazilian kefir during fermentation and storage processes. J. Dairy Sci. 96:4149-4159. https://doi.org/10.3168/jds.2012-6263
Lengkey, H. A. W. 2002. Pengaruh penggunaan bermacam susu terhadap kadar pH dan pertambahan berat butiran kefir. Jurnal Ilmu Ternak 2: 38-41.
Lengkey, H. A. W., J. A. Siwi, & R. L. Balia. 2013. The effect of various starter dosages on kefir quality. Lucrări Ştiinţifice-Seria Zootehnie 59:113-116.
Lengkey, H. A. W. & R. L. Balia. 2014. The effect of starter dosage and fermentation time on pH and Lactic acid production. Biotechnology in Animal Husbandry 30: 339-347. https://doi.org/10.2298/BAH1402339L
Miguel, M. G. D. C. P., P. G. Cardoso, K. T. Magalhães-Guedes, & R. F. Schwan. 2011. Profile of microbial communities present in tibico (sugary kefir) grains from different Brazilian States. World J. Microbiol. Biotechnol. 27: 1875–1884. https://doi.org/10.1007/s11274-010-0646-6
Paseephol, T. & F. Sherkat. 2009. Probiotic stability of yoghurts containing Jerusalem artichoke inulins during refrigerated storage. Journal of Functional Foods 1: 311-318. https://doi.org/10.1016/j.jff.2009.07.001
Pogačić, T., S. Šinko, S. Zamberlin, & D. Samaržija. 2013. Microbiota of kefir grains. Mljekarstvo 63:3-14.
Purbasari, N., A. Hantoro-DR, & S. Wasito. 2013. Pengaruh konsentrasi biji kefir dan waktu fermentasi terhadap viskositas dan penilaian organoleptik kefir susu kambing (The influence of the concentration of seeds kefir and time fermentation against viscosity and judgment organoleptic kefir milk of goat). Jurnal Ilmiah Peternakan 1:1021-1029.
Purnomo, H. & L. D. Muslimin. 2012. Chemical characteristics of pasteurised goat milk and goat milk kefir prepared using a different amount of Indonesian kefir grains and incubation times. J. Inter. Food Research. 19:791-794.
Setyawardani, T., A. H. D. Rahardjo, M. Sulistyowati, & S. Wasito. 2014. Physiochemical and organoleptic features of goat milk kefir made of different kefir grain concentration on controlled fermentation. Anim. Prod. 16:48-54.
Standar Nasional Indonesia (Indonesian National Standar). 2009. SNI Nomor 7552:2009 tentang Minuman Susu Fermentasi Berperisai.
Suharto, E. L. S., I. I. Arief, & E. Taufik. 2016. Quality and antioxidant activity of yogurt supplemented with Roselle during cold storage. Med. Pet. 39:82-89. https://doi.org/10.5398/medpet.2016.39.2.82
Sulmiyati, N. S. Said, D. U. Fahrodi, R. Malaka, & F. Maruddin. 2018a. The characteristics of lactic acid bacteria isolated from Indonesian commercial kefir grain. Malays. J. Microbiol. 14:632-639. https://dx.doi.org/10.21161/mjm.117317
Sulmiyati., N. S. Said, D. U. Fahrodi, R. Malaka, & F. Maruddin. 2018b. Perbandingan kualitas fisiokimia kefir susu kambing dengan susu sapi (Comparison of physiochemical quality of goat milk kefir with cow milk kefir). Jurnal Veteriner 19: 263-268. https://doi.org/10.19087/jveteriner.2018.19.2.263
Swanson, K. M. J., F. F. Busta, E. H. Peterson, & M. Jonhson. 1992. Colony Count Methods. In: C. Vanderzant., D.F. Splittsoesser (Eds). Compendium of Methods for The Microbiology Examination of Foods. 3rd edition. The APHA Technical Commite on Microbiology Methods for Foods.
Taş, T. K., F. Y. Ekinci, & Z. B. Guzel-Seydim. 2012. Identification of microbial flora in kefir grains produced in Turkey using PCR. J. Dairy Tech. 65:126–131. https://doi.org/10.1111/idt.2011.65.issue-1
Vardjan, T., P. M. Lorbeg, I. Rogelj, & A. Čanžek Majhenič. 2013. Characterization and stability of lactobacilli and yeast microbiota in kefir grains. J. Dairy Sci. 96:2729–2736. https://doi.org/10.3168/jds.2012-5829
Wang, S. Y., H. C. Chen, J. R. Liu, Y. C. Lin, & M. J. Chen. 2008. Identification of yeasts and evaluation of their distribution in Taiwanese kefir and viili starters. J. Dairy Sci. 91:3798–3805. https://doi.org/10.3168/jds.2007-0468
Wihansah, R. R. S., I. I. Arief, & I. Batubara. 2018. Anti-diabetic potency characteristics of probiotic goat-milk yogurt supplemented with roselle extract during cold storage. Trop. Anim. Sci. J. 41:191-199. https://doi.org/10.5398/tasj.2018.41.3.191
Wszolek, M., A. Y. Tamime, D. D. Muir, & M. N. I. Barclay. 2001. Properties of kefir made in Scotland and Poland using bovine, caprine and ovine milk with different starter culture. LWT-Food Science and Technology 34:251-261. https://doi.org/10.1006/fstl.2001.0773
Witthuhn, R. C., T.Schoeman, & T. J. Britz. 2004. Isolation and characterization of the microbial population of different South African keﬁr grains. J. Dairy Tech. 57: 33–37. https://doi.org/10.1111/j.1471-0307.2004.00126.x
Witthuhn, R. C., T. Schoeman, & T. J. Britz. 2005. Characterisation of the microbial population at different stages of kefir production and kefir grain mass cultivation. J. Dairy Sci. 15. 383-389. https://doi.org/10.1016/j.idairyj.2004.07.016
Yilmaz-Ersan, L. Y., T. Ozcan, A. K. Bayizit, & S. Sahin. 2016. The antioxidative capacity of kefir produced from goat milk. Int. J. Chem. Eng. Appl. 1:22-26. https://doi.org/10.7763/IJCEA.2016.V7.535
Yulianti, C. H. 2014. Uji beda kadar alkohol pada tape beras, ketan hitam dan singkong. Jurnal Teknika 6:531-536.
Yusriyah, N. H, & R. Agustini. 2014. Pengaruh waktu fermentasi dan konsentrasi bibit kefir terhadap mutu kefir susu sapi (The effect of fermentation and concentration of kefir grains of quality of cow's milk kefir). UNESA Journal of Chemistry 3:53-57.
Zhou, J., X. Liu, H. Jiang, & M. Dong. 2009. Analysis of the microflora in Tibetan kefir grains using denaturing gradient gel electrophoresis. J. Food Micro. 26: 770–775. https://doi.org/10.1016/j.fm.2009.04.009
This work is licensed under a Creative Commons Attribution-ShareAlike 4.0 International License.
Authors submitting manuscripts should understand and agree that copyright of manuscripts of the article shall be assigned/transferred to Tropical Animal Science Journal. The statement to release the copyright to Tropical Animal Science Journal is stated in Form A. This work is licensed under a Creative Commons Attribution-ShareAlike 4.0 International License (CC BY-SA) where Authors and Readers can copy and redistribute the material in any medium or format, as well as remix, transform, and build upon the material for any purpose, but they must give appropriate credit (cite to the article or content), provide a link to the license, and indicate if changes were made. If you remix, transform, or build upon the material, you must distribute your contributions under the same license as the original.