Development of a novel pomegranate standard and new method for the quantitative measurement of pomegranate polyphenols

Abstract BACKGROUND: The Folin–Ciocalteu method is routinely used to calculate total polyphenol concentrations (TPP) in food products. However, the use of inappropriate standards such as gallic acid (GA) may give inaccurate estimates of TPP content. A method for the production of a pomegranate ( Punica granatum L. ‘Wonderful’) standard was developed and validated to avoid this problem. The PPS was produced by solid phase (C18) isolation of polyphenols from POMx powder (a nutritional supplement) and used for TPP analysis. RESULTS: TPP content of POMx was > 90% using PPS, whereas the GA standard underestimated TPP by up to 30%. Compositional analysis confirmed a balance of about 9% non‐polyphenolic compounds. Mass spectrometry analysis corroborated polyphenol composition and confirmed pomegranate‐specific peaks, i.e., punicalagin and punicalin. CONCLUSION: Results support the use of pomegranate‐specific standards to accurately determine TPP. Copyright © 2008 Society of Chemical Industry