PEMBUATAN BIOETANOL DARI KULIT DAN JERAMI NANGKA (Artocarpus heterophyllus Lamk) DENGAN VARIASI NISBAH KO-KULTUR RAGI

Bioethanol is an alternative energy substitute for fuel that is made from glucose fermentation. Glucose can be obtained from waste with a composition of cellulose and starch, for example jackfruit skin and straw. This study aims to produce bioethanol from jackfruit peel and straw with variations in yeast co-culture ratios. The process of making bioethanol begins with drying, grinding, and sifting using a 70-mesh sieve to produce jackfruit peel and straw powder. Jackfruit peel and straw powder were hydrolyzed with 1M HCl at 120oC for 2 hours. The hydrolyzed filtrate was fermented for 4 days using variations in yeast co-culture ratio such as baker's yeast T1 (0:3), tape yeast T2 (3:0), co-culture of tape yeast and baker's yeast with a weight ratio of 1:1 (T3), co-culture of tape yeast and baker's yeast with a ratio of 2:1 (T4), and co-culture of tape yeast and baker's yeast with a ratio of 1:2 (T5). Separation of bioethanol was carried out with simple distillation. Qualitative testing was carried out with the potassium dichromate test and quantitative testing was carried out with gas chromatography. The bioethanol content resulting from the quantitative test on the variations T1, T2, T3, T4, and T5 respectively was 0.360%; 0.155%; 0.145%; 0.17%; and 0.13%. The qualitative tests T1 and T3 showed a color change from orange to blue, while T2; T4; and T5 underwent a color change from orange to greenish brown. The highest bioethanol content was obtained from the variation of baker's yeast T1 (0:3) of 0.360% with a color change from orange to blue, which proves the presence of bioethanol. Based on these results, jackfruit peel and straw can be used as a base for bioethanol