Umbi Yakon dapat difermentasi dengan bakteri kultur starter Lactobacillus plantarum B1765 menghasilkan SCFA. SCFA dapat bermanfaat untuk kesehatan. Umbi Yakon dapat difermentasi dengan bakteri kultur starter Lactobacillus plantarum B1765 yang dapat dimanfaatkan sebagai alternatif produk kesehatan. Tujuan dari penelitian ini adalah 1. Untuk mengetahui pengaruh waktu fermentasi umbi yakon dengan bakteri kultur starter Lactobacillus plantarum B1765 terhadap total BAL. 2. Untuk mengetahui pengaruh waktu fermentasi umbi yakon dengan bakteri kultur starter Lactobacillus plantarum B1765 terhadap pH. 3. Untuk mengetahui pengaruh waktu fermentasi umbi yakon dengan bakteri kultur starter Lactobacillus plantarum B1765 terhadap profil produksi SCFA dan asam laktat selama proses fermentasi umbi yakon dengan bakteri kultur starter Lactobacillus plantarum B1765, dan mengetahui waktu fermentasi optimum dalam menghasilkan SCFA dan asam laktat. Jenis penelitian yang digunakan adalah penelitian eksperimen sesungguhnya. Rancangan Penelitian yang digunakan adalah The Post Test Only Control Group Design. Dalam penelitian ini, dilakukan pengujian pH, Total BAL menggunakan metode Total Plate Count, dan SCFA. Hasil menunjukkan bahwa semakin lama proses fermentasi maka pH semakin asam. Umbi yakon difermentasi menggunakan Bakteri kultur starter Lactobacillus plantarum B1765 selama beberapa perlakuan yaitu 3 jam, 12 jam, 24 jam, 36 jam, 48 jam, 60 jam, dan 72 jam.  Rata-rata Total BAL fermentasi 24,09.10⁷ CFU / mL, 12,70.10⁸ CFU / mL, 21,56.10⁸ CFU / mL, 26,77,10⁸ CFU / mL, 36,35.10⁸ CFU / mL, 39,54.10⁸ CFU / mL, dan 47,81.10⁸ CFU / mL. Rata-rata Total BAL mengalami kenaikan dan menunjukkan bahwa semakin lama proses fermentasi maka semakin tinggi konsentrasi BAL. pH yang didapatkan berturut-turut adalah 4.33, 3.66, 3.54, 3.45, 3.35, 3.12, dan 2,48. Hasil menunjukkan bahwa semakin lama fermentasi, pH akan semakin asam/rendah. Hasil fermentasi selama 3 jam, 24 jam, 48 jam,dan 72 jam menghasilkan asam asetat 335,71 ppm, 81,029 ppm, 102,466 ppm, 90,67 ppm. Hasil fermentasi selama 3 jam, 24 jam, 48 jam, dan 72 jam menghasilkan asam propionat sebesar 30,165 ppm, 60,047 ppm, 83,368 ppm, dan 85,354 ppm. Hasil fermentasi 3 jam, 24 jam, 48 jam, 72 jam menghasilkan asam butirat 1004,72 ppm, 0 ppm, 2235,38 ppm, dan 85,354 ppm. Hasil fermentasi selama 3 jam 24 jam, 48 jam, dan 72 jam menghasilkan asam laktat 200,082 ppm, 536,762 ppm, 662,792 ppm, dan 550,653 ppm.

  Kata Kunci : Umbi Yakon, SCFA, Asam Laktat Fermentasi, Lactobacillus plantarum B1765.

    Yacon tuber can be fermented with starter culture of bacteria  Lactobacillus plantarum B1765 to produce scfa. SCFA can be beneficial for health. Yakon tuber can be fermented with starter culture bacteria Lactobacillus plantarum B1765 then can be used as alternative health products. The purpose of this study are 1. To know the effect of yakon tuber fermentation with Lactobacillus plantarum B1765 starter culture bacteria on total BAL. 2. To know the effect of yakon fermentation time on Lactobacillus plantarum B1765 starter culture bacteria on pH, and 3. To determine the effect of yakon tuber fermentation with Lactobacillus plantarum B1765 starter culture bacteria on the profile of SCFA production and lactic acid during yakon tuber fermentation with bacteria starter culture of Lactobacillus plantarum B1765, and find out the optimum fermentation time in producing SCFA and lactic acid.The type of research used is experimental research because there are variables of research, control, control, and sampling randomly during testing. The research design used is The Post Test Only Control Group Design. In this research, pH, Total BAL using Total Plate Count Method, and SCFA were tested. Average total fermentation BAL are  24,09.10⁷ CFU / mL, 12,70.10⁸ CFU / mL, 21,56.10⁸ CFU / mL, 26,77,10⁸ CFU / mL, 36,35.10⁸ CFU / mL, 39,54.10⁸ CFU / mL, and 47,81.10⁸ CFU / mL. The average total BAL has increased and shows that the longer the fermentation process, the higher the concentration of BAL. The pH obtained are 4.12, 3.56, 3.3, 3.25, 3.19, 3.04, and 2.69. The results show that the longer the fermentation, the more acidic / low the pH will be. The results of fermentation for 3 hours, 24 hours, 48 ​​hours, and 72 hours produced acetic acid 335.71 ppm, 81.029 ppm, 102.466 ppm, 90.67 ppm. The results of fermentation for 3 hours, 24 hours, 48 ​​hours, and 72 hours produced propionic acid at 30,165 ppm, 60,047 ppm, 83,368 ppm, and 85,354 ppm. The fermentation results were 3 hours, 24 hours, 48 ​​hours, 72 hours producing butyric acid 1004.72 ppm, 0 ppm, 2235.38 ppm, and 85.354 ppm. The fermentation results for 3 hours 24 hours, 48 ​​hours, and 72 hours produced lactic acid 200,082 ppm, 536,762 ppm, 662,792 ppm, and 550,653 ppm.

Keywords : yacon, SCFA, Lactic Acid, Fermentation, Lactobacillus plantarum B1765.