In vitro gas production of fermented cocoa pod (Theobroma cacao) added with cellulolytic inoculum from cattle rumen fluid

Abstract

This research was conducted to investigate the effect of level of cellulolytic inoculum from cattle rumen fluid in cocoa pod (Theobroma cacao) fermentation on in vitro gas production. The first stage of this experiment was getting cellulolytic microbes from rumen fluid, followed by producing microbial biomass as inoculum. In the second stage, cocoa pod as much as 300 g were fermented by addition of cellulolytic inoculum. The level of inoculum were 0%, 5% and 10% (dry matter basis). Each treatment was consisted of three replicates. Fermentation were done anaerobically, at room temperature for 21 days. The variables being measured were pH value, glucose and lactic acid content, chemical composition including dry matter (DM), organic matter (OM), crude fiber (CF), crude protein (CP), ether extract (EE), and nitrogen free extract (NFE) being produced, as well as in vitro gas production. The data obtained were analyzed using variance analysis of one way design. The differences between mean values were analyzed using Duncan’s new multiple range test (DMRT). The result showed that addition of 10% cellulolytic inoculum didn’t affect glucose and lactic acid content, but pH value of fermented cocoa pod with cellulolytic inoculum addition was lower than control. In general, there was no effect of cellulolytic inoculum addition on chemical composition and
in vitro gas production were observed, except for CF and NFE. The addition of cellulolytic inoculum 5% and 10% decreased CF content by 3.91% and 5.74%, and increased NFE content by 5.24% and 10.52%, respectively compared to control. It can be concluded that cellulolytic inoculum improves chemical quality of cocoa pod by decreasing CF and increasing NFE, however it doesn’t affect to in
vitro gas production.