Cultivation and Fractionation of Leguminous Biomass for Lactic Acid Production

Chemical industries are set to increase the proportion of renewable feedstock in their production in the decades ahead. Green Biorefineries that divide fresh green biomass into cakes and juice deliver valuable products for various industrial uses. Press juice can be used to produce lactic acid (LA), a promising building blok for the future. In this study, optimal cultivation and fractionation processes for generating a fermentation medium from legumes for lactic acid production by Bacillus coagulans are analyzed. The contents of press juices from alfalfa cultivated on arable land at three different sites and from a clover-grass mixture on a grassland site taken on different sampling dates are compared. In addition, fresh biomass yields from the different biomass samples are examined. This paper focuses on the methods applied, and provides initial results. Yield differences of up to 40 % and 60 % were recorded between different study sites and sampling dates, respectively. Fermentation analysis of the different samples revealed that press juices can supplement the main parts of nutrients for lactic acid bacteria, producing economically interesting amounts of lactic acid. These findings could increase the use of lactic acid in chemical industries and bring about a shift towards a higher proportion of renewables, namely legumes, in the processing chain.