Ohmic heating for polyphenol extraction from grape berries: an innovative prefermentary process

High energy consumption is often required to increase the extraction of phenolic compounds from grapes during alcoholic fermentation. Processes such as thermovinification require significant temperature changes over a long period time ensure diffusion grape skin layer must. In this study, capability ohmic heating (OH) process (E = 55 V/cm, t 60–90 s, T 72 °C) improve extractability valuable intracellular skins Aglianico and Barbera matrices before fermentation stepAs similarly reported by Donsì et al. (2010), any tissue damage occurring after application either conventional or was not found influence rate investigated compared with both untreated thermally (CH) treated (T °C, 90 s) samples. Total phenolics antioxidant capacity were monitored (10 days). comparison thermal treatment, results showed that compound content musts twice high immediately OH treatment. This could drastically classic prefermentary maceration (thermovinifications, cold macerations, etc.) time. finished wines produced musts, total polyphenolic up 17 % higher than CH wines, 30 wines. No differences in concentrations tannins anthocyanins observed between heated musts. However, an 200 for some aromatic esters Overall, outcomes work proved that, addition effect, moderate electric field (MEF) applied has potential induce instantaneous release due electroporation phenomenon cell membranes, thus saving reducing processing