Quality control of red clover based nutritional supplements by FTIR and chemometric analysis

Botanical preparations of red clover (Trifolium pratense L.) have gained interest as an alternative treatment for menopausal problems such as hot flushes. This shows the need for simple and rapid analysis methods. In the present study, FTIR-ATR spectroscopy has been applied for the characterization and identification of the active compounds of red clover belonging to the class of isoflavones, e.g. formononetin and biochanin A. Information about functional groups and chemical composition could be obtained, making FTIR a powerful tool for a fast and non-destructive quality control. Moreover, using chemometrics calibration models based on the partial least squares (PLS) regression were employed. The results of the multivariate calibration demonstrated the potential of this method to quantify the main isoflavones in red clover.