Fermentation is a crucial stage in Arabica coffee processing involving the activity of various microorganisms. This process not only affects coffee bean quality but also generates a liquid by-product with potential application as a microbe-based probiotic beverage in agroindustry. This study aimed to characterize the dynamics of microbial populations in the liquid by-product of Arabica coffee fermentation during the fermentation process. Liquid samples were collected at fermentation intervals of 5, 10, and 15 days. Analyses included total microbial enumeration using the Total Plate Count (TPC) method, isolation of lactic acid bacteria on de Man, Rogosa, and Sharpe Agar (MRSA), and Gram staining tests. The results showed a significant increase in microbial populations with increasing fermentation time. Total microbial counts reached 3.09 × 108 CFU/mL on day 5, increased to 9.20 × 108 CFU/mL on day 10, and peaked at 3.09 × 1010 CFU/mL on day 15. Microscopic observations revealed Gram-positive rod-shaped isolates at all fermentation stages, with cell density increasing from day 5 to day 15. The morphological characteristics of the isolates were consistent with the genus Lactobacillus, indicating that fermentation duration is a key factor influencing microbial population dynamics. These findings highlight the important role of microorganisms in coffee fermentation and demonstrate the potential of fermentation by-products as a source of functional microbes for agroindustrial and biotechnological applications.

[BPS]. Badan Pusat Statistik. Bener Meriah Dalam Angka 2023. Diakses pada 25 Februari 2025

Chauhan A, Jindal T. Biochemical and molecular methods for bacterial identification. In Microbiological methods for environment, food and pharmaceutical analysis 2020 Sep 19 (pp. 425-468). Cham: Springer International Publishing.

Chugh B, Kamal-Eldin A. Bioactive compounds produced by probiotics in food products. Current opinion in food science. 2020 Apr 1;32:76-82.

Dimri AG, Chaudhary S, Singh D, Chauhan A, Aggarwal M. Morphological and biochemical characterization of food borne gram-positive and gram-negative bacteria. Science Archives. 2020;1(1):16-23.

Distanbun Aceh. Statistik Perkebunan Aceh 2023. Dinas Pertanian dan Perkebunan Aceh. 2024. Provinsi Aceh

Elhalis H, Cox J, Zhao J. Ecological diversity, evolution and metabolism of microbial communities in the wet fermentation of Australian coffee beans. International journal of food microbiology. 2020 May 16;321:108544

Erkmen O, Bozoglu TF. Food microbiology, 2 volume set: Principles into practice. John Wiley & Sons; 2016 Jun 13.

Haile, M., & Kang, W. H. (2019). The role of microbes in coffee fermentation and their impact on coffee quality. Journal of Food Quality, 2019(1), 4836709.

Hakim S, Irwnsyah I, Widayat R, Baihaqi B. Analisis Kimia Kopi Cherry Arabika (Coffea arabica) dengan Kajian Kadar Alkohol, Kadar Kafein, Total Padatan Terlarut dan Total Asam Pada Limbah Hasil Fermentasi Anaerobik. Jurnal Ilmiah Membangun Desa dan Pertanian. 2024 Mar 10;9(2):172-9.

Huang Z, Habib A, Ding X, Lv H. Physiochemical and microbial analysis of Tibetan yak milk yogurt in comparison to locally available yogurt. Molecules. 2023 Jul 6;28(13):5242.

Klimko AI, Cherdyntseva TA, Brioukhanov AL, Netrusov AI. In vitro evaluation of probiotic potential of selected lactic acid bacteria strains. Probiotics and antimicrobial proteins. 2020 Sep;12:1139-48.

Liu X, Mao B, Tang X, Zhang Q, Zhao J, Chen W, Cui S. Bacterial viability retention in probiotic foods: a review. Critical Reviews in Food Science and Nutrition. 2025 Apr 4:1-23.

Madigan, M.T., Bender, K.S., Buckley, D.H., Sattley, W.M. and Stahl, D.A., 2019. Brock biology of microorganisms. Fifteenth.

Nakov G, Ninova-Nikolova N, Ivanova N, Raykova V, Trajkovska B, Čolić ML, Lukinac J, Jukić M. Yogurt enriched with chia seeds: Physicochemical, microbiological, and sensory changes during storage. Fermentation. 2024 Aug 18;10(8):431.

Nuraida L. A review: Health promoting lactic acid bacteria in traditional Indonesian fermented foods. Food Science and Human Wellness. 2015 Jun 1;4(2):47-55.

Pasquina-Lemonche L, Burns J, Turner RD, Kumar S, Tank R, Mullin N, Wilson JS, Chakrabarti B, Bullough PA, Foster SJ, Hobbs JK. The architecture of the Gram-positive bacterial cell wall. Nature. 2020 Jun 11;582(7811):294-7.

Pereira TS, Batista NN, Pimenta LP, Martinez SJ, Ribeiro LS, Naves JA, Schwan RF. Self-induced anaerobiosis coffee fermentation: Impact on microbial communities, chemical composition and sensory quality of coffee. Food Microbiology. 2022 May 1;103:103962.

Pramulya R, Bantacut T, Noor E, Yani M. desain sistem pertanian dan agroindustri kopi arabika gayo berkelanjutan di provinsi aceh (Doctoral dissertation, Tesis. Sekolah Pascasarjana, 2021. Institut Pertanian Bogor).

Rambitan G, Pelealu JJ, Tallei TE. Isolasi dan identifikasi bakteri asam laktat hasil fermentasi kol merah (Brassica oleracea L.) sebagai probiotik potensial (Isolation and identification lactic acid bacteria from red cabbage (Brassica oleracea L.) fermentation as potential probiotic). Jurnal Bios Logos. 2018 Aug 31;8(2):33-7

Rodrigues NP, Garcia EF, de Souza EL. Selection of lactic acid bacteria with promising probiotic aptitudes from fruit and ability to survive in different food matrices. Brazilian Journal of Microbiology. 2021 Dec;52(4):2257-69.

Rusman J, Michael A, Pasae N. Deteksi Tingkat Kematangan Buah Kopi Arabika Berdasarkan Fitur Warna RGB Menggunakan Sensor TCS3200 Berbasis Arduino Uno. Journal Dynamic Saint. 2021 Apr 30;6(1):60-6.

Saha UB, Saroj SD. Lactic acid bacteria: prominent player in the fight against human pathogens. Expert Review of Anti-infective Therapy. 2022 Nov 2;20(11):1435-53

Shahid S, Asslam F, Imran A. Harnessing the Potential of Crispr Technologies Across the Food Supply Chain. InCRISPR-Based Gene Editing 2025 (pp. 81-126). Apple Academic Press.

Silhavy TJ, Kahne D, Walker S. The bacterial cell envelope. Cold Spring Harbor perspectives in biology. 2010 May 1;2(5):a000414.

Singh, S., Kumar, A., & Yadav, A. N. (2022). Gram staining and its applications in microbiology: A comprehensive review. Frontiers in Microbiology, 13, 937845. https://doi.org/10.3389/fmicb.2022.937845

Sionek B, Szydłowska A, Trząskowska M, Kołożyn-Krajewska D. The impact of physicochemical conditions on lactic acid bacteria survival in food products. Fermentation. 2024 Jun 4;10(6):298.

Siregar, Z. A., Susanty, D., & Suthamihardja, R. (2020). Fermentasi Biji Kopi Arabika (Coffea arabica L.) dengan Penambahan Bakteri Asam Laktat (Lactobacillus sp.). Jurnal Sains Natural, 10(2), 87-94.

Usman, I., & Magaji, M. (2025). Isolation and Identification of Lactic Acid Bacteria From Cow Milk and Milk Products. Kashf Journal of Multidisciplinary Research, 2(09), 27-42.

Wang, H., Chen, Y., & Liu, Y. (2021). Advances in the taxonomy and identification of Gram-negative bacteria of clinical significance. Journal of Clinical Microbiology, 59(12), e00921-21. https://doi.org/10.1128/JCM.00921-21

Won SM, Chen S, Park KW, Yoon JH. Isolation of lactic acid bacteria from kimchi and screening of Lactobacillus sakei ADM14 with anti-adipogenic effect and potential probiotic properties. Lwt. 2020 May 1;126:109296.

Xu H, Wu N, Na N, Ding H, Sun L, Fang Y, Li D, Li E, Yang B, Wei X, Xue Y. Dynamics of fermentation quality, bacterial communities, and fermentation weight loss during fermentation of sweet sorghum silage. BMC microbiology. 2024 Oct 23;24(1):429.

Yi L, Qi T, Hong Y, Deng L, Zeng K. Screening of bacteriocin-producing lactic acid bacteria in Chinese homemade pickle and dry-cured meat, and bacteriocin identification by genome sequencing. LWT. 2020 May 1;125:109177.

Zeng Y, Li Y, Wu QP, Zhang JM, Xie XQ, Ding Y, Cai SZ, Ye QH, Chen MT, Xue L, Wu S. Evaluation of the antibacterial activity and probiotic potential of Lactobacillus plantarum isolated from Chinese homemade pickles. Canadian Journal of Infectious Diseases and Medical Microbiology. 2020;2020(1):8818989.

Zhang, H., Dong, Y., & Yang, Z. (2021). Structure and function of Gram-positive bacterial cell walls: From molecules to cells. Critical Reviews in Microbiology, 47(4), 443–456. https://doi.org/10.1080/1040841X.2021.1903502