Ev Yapımı Kombu Çayı Üretiminde Mikrobiyolojik Kontaminasyon Riskinin Değerlendirilmesi

Abstract

Kombu çayı, sağlık üzerindeki etkileri ile son zamanlarda dikkat çeken önemli bir fermente içecektir. Ticari olarak üretimi ve satışı olmakla birlikte sağlık üzerindeki etkileri ve ev yapımı gıdaların ticari olanlara kıyasla daha güvenilir olacağı gibi sebeplerle ev yapımı olarak da üretilmekte ve tüketilmektedir. Mevcut çalışma, ev yapımı Kombu çaylarının mikrobiyolojik güvenilirliğini gıda güvenliği ve halk sağlığı açısından değerlendirmek amacıyla gerçekleştirilmiştir. Bu amaçla Kombu çayının bakteri ve mayalarının simbiyotik kültürü (SCOBY) 10 eşit parçaya bölünmüş 1’i kontrol olarak laboratuvar ortamında tutulmuş, 9’u ise birbirinden habersiz gönüllü hanelere, Kombu çayı hazırlamak için oluşturulmuş kit ve fermentasyon prosedürü ile birlikte teslim edilmiştir. Gönüllü hanelerden günlük mutfak düzeni içerisinde, rutin hijyen davranışları ile fermentasyon prosedürüne bağlı kalarak SCOBY’nin seri fermentasyonlarını gerçekleştirmeleri istenmiştir. Çalışmada her biri 14 gün süren dört seri fermentasyon gerçekleştirilmiş ve her fermentasyona ilişkin Kombu çayı örnekleri toplanmış, örneklerde koliform bakteri, Enterobactericeae, E. coli, enterokok, stafilokok ve küf mikroorganizmaları varlığı araştırılmıştır. Analizlerde, ikinci seri fermentasyon (28. gün) Kombu çayının 5. ve 6. gönüllü hane örneklerinde sırasıyla 2.69 log kob/mL ve 2.28 log kob/mL küf ve 4. gönüllü hane örneğinde 2 log kob/mL koagülaz-negatif stafilokok belirlenmiştir. Dördüncü seri fermentasyon (56. gün) Kombu çaylarında 3. gönüllü haneden alınan örnekte 2 log kob/mL koagülaz-negatif stafilokok ve 4. gönüllü hane örneğinde 1 log kob/mL koliform bakteri izole edilmiştir. Ev yapımı Kombu çaylarına ilişkin mikrobiyolojik analiz sonuçlarına göre, çalışmaya dahil olan 9 haneden 4’ünde (%44.4) üretilen çaylarda mikrobiyal kontaminasyon tespit edilmiştir. Sonuç olarak ev yapımı Kombu çaylarının, bakteri ve küf ile kontamine olabileceği ve bu durumun tüketicilerin sağlığı üzerinde risk teşkil edebileceği mevcut çalışma ile ortaya konmuştur. Tüketicilerin hazır ticari Kombu çaylarını tercih etmelerinin daha güvenli olacağı, fermentasyonu kendisi yapmak isteyen tüketicilerin ise hijyenik koşullara çok dikkat etmeleri, SCOBY’i düzenli yenilemeleri ve üretim esnasında pH ve sıcaklık kontrolü yapmaları ortaya çıkabilecek riskleri azaltmak için önerilmektedir.

Keywords

• Kombu çayı
• ev yapımı
• kontaminasyon
• küf
• bakteri

Assessment of Microbiological Contamination Risk in Homemade Kombucha Production

Abstract

The current study was conducted to assess the microbiological safety of homemade kombucha from a food safety and public health perspective. For this purpose, a symbiotic culture of kombucha bacteria and yeast (SCOBY) was divided into 10 equal parts. One was kept in the laboratory as a control, and the remaining nine were delivered to volunteer households, along with a kit and fermentation procedure designed to prepare kombucha. The volunteer households were asked to carry out serial fermentations of the SCOBY within their daily kitchen routine, adhering to routine hygiene practices and the fermentation procedure. In the study, four serial fermentations, each lasting 14 days, were conducted, and kombucha samples from each fermentation were collected and analyzed for the presence of coliform bacteria, Enterobacteriaceae, E. coli, enterococci, staphylococci, and mold. In the analyses, 2.69 log cfu/mL and 2.28 log cfu/mL of mold were detected in the 5th and 6th volunteer household samples of Kombucha tea from the second series fermentation (day 28), respectively, and 2 log cfu/mL of coagulase-negative staphylococci were detected in the 4th volunteer household sample. In the fourth series fermentation (day 56), 2 log cfu/mL coagulase-negative staphylococci were isolated in the sample taken from the 3rd volunteer household, and 1 log cfu/mL coliform bacteria were isolated in the sample taken from the 4th volunteer household in Kombucha tea. According to the results of the homemade Kombucha teas, microbial contamination was detected in the teas produced in 4 of the 9 households (44.4%). In conclusion, the current study has revealed that homemade kombucha can be contaminated with bacteria and mold, posing a health risk to consumers. It would be safer for consumers to choose commercially prepared kombucha. Those wishing to ferment their own kombucha should pay close attention to hygiene, regularly renew the SCOBY, and check pH and temperature during production to decrease potential risks.

Keywords

• Kombucha
• home-made
• contamination
• mold
• bacteria

References

1. Bishop P, Pitts ER, Budner D, Thompson-Witrick KA. Kombucha: Biochemical and microbiological impacts on the chemical and flavor profile. Food Chem Adv. 2022;1:100025. doi:10.1016/j.focha.2022.100025
2. Miranda JF, Ruiz LF, Silva CB, Uekane TM, Silva KA, Gonzalez AGM, Fernandes FF, Lima AR. Kombucha: A review of substrates, regulations, composition, and biological properties. J Food Sci. 2022;87(2):503-527. doi:10.1111/1750-3841.16029
3. Murphy TE, Walia K, Farber JM. safety aspects and guidance for consumers on the safe preparation, handling and storage of kombucha-a fermented tea beverage. Food Protect Trends. 2018;38(5):329-337.
4. Nyhan LM, Lynch KM, Sahin AW, Arendt EK. Advances in kombucha tea fermentation: A review. Appl Microbiol. 2022;2(1);73-103. doi:10.3390/applmicrobiol2010005
5. Soares MG, de Lima M, Schmidt VCR. Technological aspects of kombucha, its applications and the symbiotic culture (SCOBY), and extraction of compounds of interest: A literature review. Trends Food Sci Technol. 2021;110:539-550. doi:10.1016/j.tifs.2021.02.017
6. Onsun B, Toprak K, Sanlier N. Kombucha tea: a functional beverage and all its aspects. Curr Nutr Rep. 2025;14(1):69. doi:10.1007/s13668-025-00658-9
7. Cavicchia LOA, Ferreira de Almeida ME. The risks, toxicity and contamination of Kombucha beverage: a perspective on its production, storage, and consumption. Segur Aliment Nutr. 2024;31:e024005 doi:10.20396/san.v31i00.867425
8. Pellegrini B, Strootman LX, Fryganas C, Martini D, Fogliano V. Home-made vs industry-made: Nutrient composition and content of potentially harmful compounds of different food products. Curr Res Food Sci. 2025;10:100958. doi:10.1016/j.crfs.2024.100958

9. Sarmiento-Santos J, da Silva LA, Lourenco CAM, Rosim RE, de Oliveira CAF, Monteiro SH, Vanin FM. Assessment of quality and safety aspects of homemade and commercial baby foods. Food Res Int. 2023;174:113608. doi:10.1016/j.foodres.2023.113608
10. Mostafa H, Al Dhaheri AS, Feehan J, Yousif NM. Assessment of consumer demographics and food safety risks associated with ready-to-eat (RTE) homemade foods purchased online in the UAE. Heliyon. 2024;10(3):e24624. doi:10.1016/j.heliyon.2024.e24624
11. Yildiz E, Guldas M, Gurbuz O. Determination of in-vitro phenolics, antioxidant capacity and bio-accessibility of Kombucha tea produced from black carrot varieties grown in Turkey. Food Sci Technol. 2020;41(1):180-187. doi:10.1590/fst.00320
12. International Organization for Standardization. ISO 4832:2006: Microbiology of food and animal feeding stuffs - Horizontal method for the enumeration of coliforms - colony-count technique. Brussels, Belgium.
13. International Organization for Standardization. ISO 2158-2:2018. Microbiology of the food chain – Horizontal method for the detection and enumeration of Enterobacteriaceae - Part 2: Colony-count technique. Brussels, Belgium.
14. International Organization for Standardization. ISO 6888-1.2021. Microbiology of the food chain - Horizontal method for enumerating coagulase-positive Staphylococci (Staphylococcus aureus and other species) Part 1: Method using Baird-Parker agar medium. Brussels, Belgium.
15. International Organization for Standardization. ISO 16649-1:2018. Microbiology of the food chain-horizontal method for the enumeration of beta-glucuronidase-positive Escherichia coli-Part 1: colony-count technique at 44°C using membranes and 5-bromo-4-chloro-3-indolyl beta-D-glucuronide. Brussels, Belgium.
16. Tournas V, Stack ME, Mislivec PB, Koch HA, Bandler R. Bacteriological Analytical Manual, Chapter 18: Yeasts, Molds, and Mycotoxins, 2001.
17. Kempton L, Daly D, Kokogiannakis G, Dewsbury M. A rapid review of the impact of increasing airtightness on indoor air quality. J Build Eng. 2022;57:104798. doi:10.1016/j.jobe.2022.104798
18. World Health Organization. Regional Office for Europe. WHO guidelines for indoor air quality: dampness and mould. Published 2009. Accessed September 7 2025. https://iris.who.int/handle/10665/164348
19. Shrestha PM, Humphrey JL, Barton KE, Carlton EJ, Adgate JL, Root ED, Miller SL. Impact of low-income home energy-efficiency retrofits on building air tightness and healthy home indicators. Sustainability. 2019;11(9):2667. doi:10.3390/su11092667
20. Oliveira ÍACL, Rolim VAO, Gaspar RPL, Rossini DQ, de Souza R, Bogsan CSB. The technological perspectives of kombucha and its implications for production. Fermentation. 2022;8(4):185. doi:10.3390/fermentation8040185
21. Bromley AL. Food safety and functionality assessment of kombucha systems through bacillus cereus spore and probiotic ınoculations. Electronic Theses and Dissertations. 2021;3505.
22. Watawana MI, Jayawardena N, Gunawardhana CB, Waisundara VY. Health, wellness, and safety aspects of the consumption of kombucha. J Chem. 2015;591869. doi:10.1155/2015/591869
23. Damin BIS, Gamba V, Dettmer A, Colla LM. The kombucha phenomenon: production aspects, health benefits, and food safety issues. Braz J Dev. 2021;7(7):75548-75566. doi:10.34117/bjdv7n7-638
24. Kim J, Adhikari K. Current trends in kombucha: Marketing perspectives and the need for improved sensory research. Beverages. 2020;6(1):15. doi:10.3390/beverages6010015
25. Gölbaşι G, Akιn N, Göktepe ÇK, Demirci T. Monitoring the changes in physicochemical, sensory properties and microbiota of village-type homemade yoghurts along three consecutive back-slopping procedures. Int Dairy J. 2023;143:105663. doi:10.1016/j.idairyj.2023.105663
26. Nhabe T, Malebo NJ. Assessing microbial distribution on food preparation surfaces in old age home kitchen surfaces: a quantitative analysis. OIDA Int J Sustain Dev. 2024;17(01), 25-40.
27. Shahid AH, Nazir KNH, El Zowalaty ME, Kabir A, Sarker SA, Siddique MP, Ashour HM. Molecular detection of vancomycin and methicillin resistance in Staphylococcus aureus isolated from food processing environments. One Health, 2021;13:100276. doi:10.1016/j.onehlt.2021.100276
28. Tasanapak K, Kucharoenphaibul S, Wongwigkarn J, et al. Prevalence and virulence genes of Staphylococcus aureus from food contact surfaces in Thai restaurants. PeerJ, 2023;11:e15824. doi:10.7717/peerj.15824
29. Evans EW, Redmond EC. Domestic kitchen microbiological contamination and self-reported food hygiene practices of older adult consumers. J Food Protect. 2019;82(8):1326-1335. doi:10.4315/0362-028x.jfp-18-533
30. Türk Gıda Kodeksi Mikrobiyolojik Kriterler Yönetmeliği. Resmi Gazete Tarih: 13.02.2025, Sayı:32812.
31. Jarrell JA, Walia N, Nemergut D, Agadi A, Bennett JW. Inoculation, growth and bactericidal effects of three kombucha cultures. Microbiol Res. 2022;13(1):128-136. doi:10.3390/microbiolres13010010
32. Laavanya D, Shirkole S, Balasubramanian P. Current challenges, applications and future perspectives of SCOBY cellulose of Kombucha fermentation. J Clean Prod. 2021;295:126454. doi:10.1016/j.jclepro.2021.126454
33. Villarreal‐Soto SA, Beaufort S, Bouajila J, Souchard JP, Taillandier P. Understanding kombucha tea fermentation: a review. J Food Sci. 2018;83(3):580-588. doi:10.1111/1750-3841.14068
34. Batista P, Penas MR, Pintado M, Oliveira-Silva P. Kombucha: perceptions and future prospects. Foods. 2022;11(13):1977. doi:10.3390/foods11131977
35. Anonim. Google. Accessed September 5 2025. https://www.google.com/search?tbm=shop&q=kombucha&tbs=mr:1&sa=X&ved=0ahUKEwju8paBtcH5AhVzXvEDHcTOCA0QsysImQEoBg&biw=1366&bih=689&dpr=1