Production of medium chain fatty acids from ensiled potato peels; effect of inoculum type and kinetic study

Abstract

Medium chain fatty acids (MCFAs) are fatty acids containing 6 to 12 carbon atoms with a wide range of industrial application. They can be produced by the fermentation of waste biomass through a process called chain elongation (CE). During CE, the type of inoculum used plays a key role in determining the optimal yield of MCFAs. In this study, we showed, for the first time, the use of three different inocula including leachate, rumen fluid and digestate from a biogas reactor for the batch fermentation of ensiled potato peels for MCFAs production. Results showed that the highest chain elongation was obtained when leachate was used as inoculum with a maximum yield of 57, 4 and 26 g/kgVS for caproic acid, heptanoic acid and caprylic acid respectively. A kinetic study shows that the production of MCFAs from ensiled potato peels was better described by the first-order model than by the modified Gompertz model.