Penentuan Isolat Bakteri Asidogenik yang Mampu Menghasilkan Total Asam Tertinggi dari Limbah Cair Tahu - Andriani Sukma Witari; Irnia Nurika (Department of Agro-industrial Technology, University of Brawijaya, 2016)
Abstrak Penelitian ini bertujuan untuk mendapatkan bakteri asidogenik yang mampu memproduksi total asam tertinggi dari limbah cair tahu. Uji kemampuan asidogenik meggunakan Rancangan Acak Kelompok pola faktorial dengan menggunakan dua perlakuan yaitu persentase inokulum (5%, 10%, dan 15%) dan lama waktu inkubasi (24 jam, 48 jam, dan 72 jam). Parameter yang diukur meliputi kadar total asam tertitrasi, pH, kadar gula reduksi, dan total bakteri asidogenik. Hasil penelitian menunjukkan karakterisasi morfologi koloni isolat terpilih (isolat 1031) berwarna putih tulang, berbentuk bulat, permukaan timbul, dan tepiannnya rata dan karakterisasi morfologi sel isolat 1031 adalah Gram negatif dan berbentuk batang. Berdasarkan hasil karakterisasi biokimia, isolat 1031 memiliki probabilitas kedekatan dengan Hafnia alvei biogp 1 sebesar 94,53%. Persentase inokulum dan lama waktu inkubasi berpengaruh terhadap produksi total asam tertitrasi. Perlakuan terbaik adalah kombinasi perlakuan A3B1 (persentase inokulum 15% dan waktu inkubasi 24 jam), dengan nilai total asam tertitrasi 2,70%, nilai pH 6,33, kadar gula reduksi 0,07%, dan jumlah populasi bakteri asidogenik 1,1 x 108 CFU/ml.Kata kunci: asidogenesis, bakteri asidogenik, limbah cair tahu, dan total asam teritrasiAbstract This research had an objective to find an acidogenic bacteria which was able to produce the highest organic acid from tofu wastewater. Test of acidogenic capabilty used Randomized Block Design arranged in factorial by using two treatments, inoculum percentage (5%, 10%, and 15%) and incubation time (24 hours, 48 hours, and 72 hours). Parameters measured were production of titration acidity total, pH, degree of sugar reduction, and acidogenic bacteria total. Result showed identification of colony morphology of selected isolate (isolat 1031) were bone-white, round shape, raised surface (elevation), flat edge and cell morphology were Gram-negative bacillusshaped. Based on the biochemical identification showed isolate 1031 was Hafnia alvei biogp 1 with a probability value of 94.53%. Inoculum percentage and incubation time had significant effect in production of titration acidity total. The best treatment combination was A3B1 (inoculum percentage of 15% and incubation time in 24 hours). A3B1 treatment produced titration acidity total 2,70%, pH 6,33, degree of sugar reduction 0,07%, and acidogenic bacteria total 1,1x108 CFU/ml.Keywords: acidogenesis, acidogenic bacteria, titration acidity total, and tofu wastewater