Improvement of physico-chemical properties and phenolic compounds bioavailability by concentrating dietary fiber of peach (Prunus persica) juice by-product

BACKGROUNDThis study aimed to concentrate dietary fiber (DF) from peach (Prunus persica) juice by-product (PJBP), to improve its functional properties, and its polyphenols bioavailability. The dietary fiber concentrates (DFCs) were obtained from PJBP using water/ethanol treatments (100:0, 20:80, 50:50, 80:20, and 0:100, v/v) at 1:5 ratio (wet weight/solvent, w/v) for 5 and 20min at 21 degrees C. RESULTSAll treatments concentrated condensed tannins, total and insoluble DF, with the highest content found with 100% H2O treatment. The major polyphenols of DFC were 4-O-caffeoylquinic, chlorogenic, and 1,5-di-O-caffeoylquinic acids. Water and oil retention capacity and maximum glucose diffusion rate were improved mainly with 100% H2O treatment. Healthy rats were fed with a standard diet supplemented with 8% of PJBP, DFC obtained with 100% H2O for 5min, or DFC obtained with 20% EtOH for 5min. Gastrointestinal digesta weight and viscosity were increased in animals supplemented with 100% H2O DFC. Moreover, the urinary excretion of polyphenol metabolites, mainly glucuronide and sulfate conjugates, was increased with this treatment, indicating a greater bioavailability of PJBP polyphenols, which was associated with an increased dietary fiber porosity. CONCLUSIONWater treatment could be used to potentiate PJBP functional properties and polyphenols bioavailability. (c) 2017 Society of Chemical Industry