Grain quality determination by means of near infrared spectroscopy in Jatropha curcas L.

Jatropha curcas L. (JCL) is an important energy plant which has received great attention in recent years for its utilization in biodiesel production and its high potential for greening and rehabilitation of wastelands. Breeding, farming and industrial processing of JCL need rapid and efficient methods to determine quality parameters associated with the value of the oil, press cake and biodiesel. Wet chemistry analyses are time consuming and expensive and near-infrared spectroscopy (NIRS) might be a suitable method for the analysis of large numbers of samples. Our main goal was to investigate the potential of NIRS to determine grain quality parameters in bulk JCL samples. We concluded that NIRS has a high potential for determining concentrations of oil, protein, ash, stearic, oleic, linoleic, linolenic and arachidic acids in the kernel fraction of JCL grains. The precision of NIRS-based phorbol ester determination could be improved by excluding samples with phorbol ester <0.1 mg g−1. NIRS-based prediction of shell quality traits proved to be less accurate than for kernel traits.

► This is the first report on NIRS to determine grain quality of bulk samples in JCL. ► NIRS showed a high potential to determine quality traits in JCL kernels. ► NIRS-based determination of quality traits in shells was less precise than in kernels. ► Preliminary research on determination of phorbol ester by means of NIRS is presented for the first time.