Modification of coconut insoluble dietary fiber by enzymatic extraction and high-pressure homogenization: physicochemical property changes and inhibitory effects on pancreatic lipase activity.

In this study, coconut insoluble dietary fiber (CIDF) was modified by high-pressure homogenization (HPH), and the physicochemical properties and pancreatic lipase (PL) inhibitory activity were investigated. HPH diminished the particle size of CIDF (859.90 nm to 232.80 nm) and increased the total surface area and gap ratio. HPH enhanced the water and oil holding capacities of CIDF from 6.01 to 10.33 g/g and from 6.52 to 9.87 g/g, respectively. CIDF markedly inhibited PL activity by up to 72.51 % (p < 0.05), with the inhibition rate of PL was significantly higher in HPH-modified CIDF than in unmodified CIDF. The exposure of CIDF's hydroxyl groups due to the HPH treatment directly affected the degree of binding of CIDF to PL. CIDF reduces PL activity through hydrogen bonding and hydrophobic interactions with its aromatic amino acid residues.