Supercritical antisolvent precipitation of polyphenols from grape marc extract

[Display omitted] ⿢CO2 molar fraction showed the main effect on SAS efficiency.⿢Total polyphenols obtained by SAS ranged from 60 to 300mg GAE/100g DGM.⿢350% enrichment of total polyphenols obtained by SAS at 12MPa, 45°C, 0.99 CO2.⿢300⿿450% enrichment of proanthocyanidins obtained by SAS at 12MPa, 45°C, 0.99 CO2. Supercritical anti-solvent (SAS) conditions to obtain the maximum enrichment of total polyphenols from grape marc extract was studied by 23 factorial design. Operating at 12MPa, 45°C and 0.99 CO2 molar fraction, a relative enrichment of 350% of total polyphenols as well as a relative enrichment of proanthocyanidins fractions between 300 and 450% was achieved. Under these process conditions, microparticles in the order of 5μm size were produced. The content of the main phenolic acid (gallic acid) and flavonoids (catechin, epicatechin, quercetin, malvidin and procyanidin B2) for the different precipitates was determined using high performance liquid chromatography. Starting from 100g of grape marc, the amount of total polyphenols obtained by SAS ranged from 60 to 300mg GAE(GallicAcidEquivalent)/100g DGM(DriedGrapeMarc).