Development and evaluation of inocula combating high acetate concentrations during the start-up of an anaerobic digestion

► Inocula were developed by stepwise and shock adaptation for different durations. ► Inocula were evaluated during start-up under high acetate concentrations. ► Stepwise adapted inocula significantly reduced the lag-phase for acetate degradation. ► Adaptation for 4 or 6 weeks was required, lower durations were insufficient. ► Acetate degradation led to an almost equimolar production of methane.