Natural variability and effect of processing techniques on raffinose family oligosaccharides in pigeonpea cultivars

Abstract

High performance liquid chromatography (HPLC) was performed to determine the raffinose family oligosaccharides (RFOs) and sucrose content in 32 pigeonpea cultivars. The results showed that the RFOs in the pigeonpea seed extracts comprised of raffinose, stachyose and verbascose. The contents of raffinose, stachyose and verbascose were within the range of 1.15 to 2.55%, 2.25 to 4.05% and 2.05 to 4.05% with mean values of 1.63%, 2.97% and 2.80%, respectively. There was large level of variation of individual RFOs. Furthermore, to study the effect of post-harvest processing on the RFO contents, sprouting and cooking experiments were conducted with the seeds of the variety VBN 3 which possessed high RFO levels. Sprouting significantly reduced the RFO levels within 24 hours while cooking even up to 30 min in boiling water did not result in a considerable reduction. Among the local processing techniques, sprouting had significant effect on reducing RFOs content in pigeonpea.