Endo-inulinase involved in utilization of the plant storage polymer inulin, consisting of fructooligosaccharides with a degree of polymerization (DP) value from 2 to 60. Endohydrolysis of (2->1)-beta-D-fructosidic linkages in inulin. Plays an important role in biofuel production. Pure nonhydrolyzed inulin can be directly converted to ethanol in a simultaneous saccharification and fermentation process when combining A.niger and S.cerevisiae. Endoinulinase can digest fructooligosaccharides with high degree of polymerization (DP) values (>20) into short molecules that may be readily hydrolyzed by S.cerevisiae SUC2. Thus, introduction of an endoinulinase gene into S.cerevisiae will improve its inulin utilization and ethanol fermentation through collaboration between the heterologous endoinulinase and the invertase SUC2. Belongs to the glycosyl hydrolase 32 family.