Effect of particle size on phytochemical composition and antioxidant properties of two persimmon flours from Diospyros kaki Thunb. vars. Rojo Brillante' and Triumph' co-products

BACKGROUNDThis contribution studies the influence of the particle size of persimmon flours (from two cultivars, Rojo Brillante' and Triumph') on their primary (sugars and organic acids) and secondary (polyphenols, flavonoids and carotenoids) metabolite content, and also on their antioxidant activity, to assess whether these flours could find applications in the food industry as a potential functional ingredient. RESULTSThe main sugars were fructose and glucose and the principal organic acid was malic acid. The highest content of total phenols, flavonoids and carotenoids was found in flour fractions from cv. Rojo Brillante'. The phenol profile determined by HPLC identified six phenolic compounds in both persimmon flours, the most abundant being gallic acid. The greatest ABTS and DPPH radical scavenging capacity and ferric reducing power were found in flour fractions from cv. Rojo Brillante'. Although the influence of particle size on all these properties was not always evident, in general, the higher bioactive compound content and antioxidant capacity were in the finest particles. CONCLUSIONCo-products from cvs. Rojo Brillante' and Triumph' persimmon juice extraction can be processed to obtain flours rich in sugars, organic acids and bioactive compounds, suggesting their possible use as a functional ingredient (with antioxidant properties) in different food products. (c) 2017 Society of Chemical Industry