After prolonged storage, all wines produced from grapes PEF-treated with four different processing conditions were shown to favor high retention of phenolics after storage but induced faster reduction of anthocyanins when compared to wines produced from untreated grapes. Extreme storage temperature, at 45 ☌ particularly, resulted in a higher amount of linalool-3, 7-oxide in all stored wines. Results showed that hydroxycinnamic and hydroxybenzoic acids in all stored wines, regardless vinified from untreated and PEF-treated grapes, increased as a function of time and temperature, while anthocyanins and selected esters (e.g., ethyl butanoate) decreased. Wines produced from untreated grapes and those PEF-treated at four different processing conditions (electric field strength 33.1 and 41.5 kV/cm and energy inputs between 16.5 and 49.4 kJ/kg) were used for the bottle storage study. This study aimed to elucidate changes in volatile, phenolic, and oenological profiles of wines vinified from Pulsed Electric Fields (PEF)-treated and untreated Merlot grapes during bottle storage of up to 150, 90, and 56 days at 4 ☌, 25 ☌, and 45 ☌, respectively, through chemometrics technique. Selected data are presented in this paper. Must and wine made from the grape varieties Pinot Noir and Riesling have been chemically analyzed. Based on the measurements, an estimation about the energy consumption and efficiency of the device has been made.
The data logged during one exemplary run are presented in this paper. To facilitate the evaluation of the experimental results, the electroporation device has been equipped with different sensors and measurement systems, e.g., for the power drawn from the grid and the temperature of the mash before and after the electroporation. During this year's experiments, some experience in the operation of the electroporation device on-site in a winery has been gained. All together, more than 5 m3 of mash has been treated. During the harvest in 2008, the electroporation device KEA-WEIN has been operated successfully in two wineries. For white wine, the formation of pores in the cells fosters, among others, the extraction of flavoring substances.
#Mash and grape skin
In the course of the production of red wine, electroporation of mash enables a fast extraction of the red pigments from the skin without remarkable heating of the mash.