Methods for the estimation of protein in pigeonpea [Cajanus cajan (L.) Millsp.] and the relationship between whole grain and dhal protein contents uri icon

abstract

  • Proteindeterrninations of 172 grain and dhal (decorticated dry split seed) pigeonpeasamples were carried out using three methods: (a) rnicrow Kjeldahl (MKJ), (b) colorimetricestimation of NH4+ with phenol hypochlorite reagents qsing the TechniconAuto-Analyser (TAA), and (c) dye-binding capacity (DBC) method using Acid Orange12 dye: Protein perceIltages determined by the TAA and MKJ methods were highlycorrelated for whole-grain (0'948**) and dhal (0ยท967**) samples. The DBC methodgave reliable results for dhal samples only. In the DBC procedure, higher protein percentageswere recorded with smaller flour par'tides and longer mixing time, but differenttemperatures and durations of heating had no effect. Positive and highly significantcorrelations were obtained between the protein values of whole-grain and dhal samplesin all the methods. Small irains gave a lower correlation between whole-grain anddhal protein content due to the observed negative c;:orrelation between grain size andpercentage of seed~coat

publication date

  • 1981
  • 1981