Optimisation of phenol extraction from wine using layered double hydroxides and technological evaluation of the bioactive-rich powder

The purpose of this study was to extract functional components, such as phenols, from wine under mild conditions and without the use of organic solvents. A dry and alcohol-free concentrated wine bioactive extract was obtained using layered double hydroxides (LDHs). The influence of some factors (LDH type, temperature, time and LDH/wine ratio) was evaluated using an experimental design software. Three responses were selected (phenol, anthocyanin and catechin contents). Using the optimised results, the best extraction conditions were as follows: pH 3.7, time 240 min, ratio 3, temperature 20 °C. The sample prepared in these conditions was characterised technologically (size, flowability, wettability) to investigate its manageability and workability. The phenol extract obtained using MgAl-LDH had suitable particle size and good flowability. A formulation of concentrated wine phenol extract with interesting applications for the nutraceutical field was successfully produced.