Assessment of bioactive compounds in faba bean using infrared spectroscopy

Faba bean is growing in popularity in Australia, partly due to its higher levels of health-benefiting compounds compared to other grain crops. This study investigated the prospect of using infrared spectroscopy to predict levels of bioactive compounds such as antioxidants and phenolics in faba bean flour. Ninety samples of faba bean comprising ten varieties grown across two field locations and two years were utilised. Near-infrared spectroscopy showed promise for the prediction of total phenolic content, with a R 2 CV value of 0.64, RMSECV of 59 mg/100 g and RPD of 1.65. Similarly, prediction of ferric reducing antioxidant power (FRAP), a measure of antioxidant activity, gave a R 2 CV value of 0.55, RMSECV of 63 mg/100 g and RPD of 1.5. Fourier transform infrared spectroscopy also showed some promise, although typically provided a lower accuracy compared to NIRS. Although the models developed were not capable of exactly quantifying phenolic or antioxidant content, infrared spectroscopy appears useful for rapidly discriminating between samples containing high and low levels of phenolics or antioxidant compounds. With further refinement, this technique could potentially be applied for the quality assurance of phenolic content or antioxidant capacity in the faba bean crop.