Calorimetry, chemical composition and in vitro digestibility of oilseeds

The objective of the study was to determine the quality of sunflower, soybean, crambe, radish forage and physic nut, by measuring chemical composition, in vitro digestibility and kinetics of thermal decomposition processes of mass loss and heat flow. Lipid was inversely correlated with protein of whole seed (R = −0.67), meal (R = −0.95), and press cake (R = −0.78), and positively correlated with the enthalpy (ΔH) of whole seed. Soybean seed and meal presented a high in vitro digestibility but poor energy sources with ΔH averaging 5907.5 J/g and 2570.1 J/g for whole seed and meal, respectively. As suggested by the release of heat, measured by ΔH, whole seeds of crambe (6295.1 J/g), radish forage (6182.7 J/g), and physic nut (6420.0 J/g) may be potential energy sources for ruminant animals. The thermal analysis provided additional information besides that obtained from the usual wet chemistry and in vitro measurements.