u00b0 c the diffusion can be rather long up to 4 hours whereas at a higher temperature between 40 u00b0 c and 60 u00b0 c the diffusion is between 1 hour and 1 5 hours typically increasing the diffusion temperature from 20 u00b0 c to 60 u00b0 c makes it possible to increase the extracted polyphenols content of the solvent by 33 and antioxidant activity by 48 after 60 minutes of extraction on an industrial scale the diffusion temperature can be between 50 u00b0 c and 60 u00b0 c for example the diffusion is carried out in a hydroalcoholic solvent or a solvent composed of ethyl acetate if during the electrical treatment with hved or pef the grape pomace is submerged in a hydroalcoholic solvent or a solvent composed of ethyl acetate this solvent can be the same as used for the electrical treatment and the diffusion the hydroalcoholic solvent is a mixture of water and alcohol with an alcohol content varying from 25 to 50 by weight the water can be distilled water or tap water the alcohol can be methanol or ethanol nevertheless ethanol is preferable for a subsequent use of the extracted molecules in the field of foods if ethyl acetate is used it can be used in a mixture with ethanol or methanol the ethyl acetate alcohol mixture includes between 5 and 30 ethyl acetate it is also possible to use a ternary ethyl acetate alcohol water mixture preferably a ternary ethyl acetate ethanol water mixture in volume proportions notably between 4 1 4 and 10 1.