Fermentation time difference of nixtamalized horse dent corn (Zea mays var. indenata) by Bifidobacterium bifidum and Bifidobacterium brevis as source of natural folic acid

Bifidobacterium sp. as microbes has potential role in fermentation of nixtamalized horse dent corn (Zea mays var. indentata) to degrade complex components into folic acid-rich corn biomass. Fermentation process on both nixtamalized yellow corn and white corn by Bifidobacterium brevis and Bifidobacterium bifidum as substrat of A, B, C and D were conducted at concentration of corn folic acid inoculum 40% (w/w) and 37 °C for 0, 8, 16, and 24 hours, respectively. Based on dissolved protein yielded, the experiment result showed that the best result of optimization in fermentation of both nixtamalized yellow corn (biomass B) and white corn (biomass D) was achieved by using inoculum of B. bifidum for 16 hours with composition of folic acid of 213.58 and 297.72 μg/mL, total solids of 21.14 and 21.07%, dissolved protein of 0.42 and 0.39 mg/mL, reducing sugars of 34.2 and 37.8 mg/mL, total sugars of 104.7 and 98.6 mg/mL, total acids of 0.37 and 0.44%, N-amino of 0.28 and 0.26 mg/g, and pH 4.82 and 4.49, respectively. In this condition, biomass of B. and biomass of D indicated domination of folic acid monomer with molecular weight (MW) 442.29 and 442.59 Dalton (Da.) at relative intensity 100%, particles size of 1115.1 nm and 1075.7 nm, and particle index of 0.827 and 0.849, respectively. Meanwhile, volatile compounds were dominated by 2,3-butanediol of 4.46 and 10.65%, palmitic acid of 7.63 and 8.26%, octadecenoic acid of 6.31 and 9.5%, lactic acid of 2.37% and 0.53%, respectively.