Effective clean-up and ultra high-performance liquid chromatography-tandem mass spectrometry for isoflavone determination in legumes

The recoveries obtained by spiking the lentil samples with a standard mixture of isoflavones at three levels of fortification (5, 25 and 100 μg kg−1) were in the range of 54.4-111.1%, 68.6-91.1%, and 84.4-114%, respectively. The method was applied to analyse 48 lentil samples from central Italy and pulses for determining the isoflavone content, which was found to range from 1.1 to 95.6 μg kg−1.