High-pressure recovery of anthocyanins from grape skin pomace (Vitis viniferacv. Teran) at moderate temperature

Abstract

The objective was to evaluate the influences of the high hydrostatic pressure extraction parameters on the recovery of anthocyanins from the grape skin pomace extracts (Vitis vinifera cv. Teran) under moderate temperatures. Studied parameters were: solvents (methanol and ethanol); solvent concentrations (30, 50, and 70%); pressures (300, 400, and 500 MPa); times (3, 6.5, 10 min); and temperatures (22, 26, 30 °C). Predominant anthocyanins in all extracts were malvidins (malvidin-3-glucoside as the main compound) representing 55.77% of overall anthocyanin content. The type of solvent did not significantly influence anthocyanin extraction yield, while decreased solvent concentration (increased solvent-to-water ratio) significantly improved extraction of anthocyanins. Increase of pressure enhanced extraction yield of the anthocyanins but temperature showed stronger impact on the anthocyanins recovery. This investigation evidenced that the best conditions for HHPE of anthocyanins from grape pomace were extraction time 3.39 min, extraction temperature 29.48 °C, pressure 268.44 MPa and solvent concentration 70%. Practical applications Due to increased interest for the use of cheap winery byproducts as a source of expensive polyphenols for functional food production, skins from grape pomace became valuable raw material. Therefore, there is a need to evaluate the influence of HHPE innovative extraction technology on its nutritive value during processing. Optimizing parameters for polyphenolic recovery from grape pomace is directly related with nutritional value and economics of food engineering during industrial processing. Obtained results showed that the HHPE under lower temperatures is suitable for the extraction process of anthocyanins from grape skin pomace, but more research is needed to identify other food-grade solvents with their corresponding concentrations that are useful for the extraction assisted with high hydrostatic pressure.