Gheorghe Emil Bandici

The effect of pulsed electric field (PEF) treatment on the quality of wine

This paper analyses the influence of applying PEF treatment to mash obtained from red grapes (Pinot Noir and Merlot) on the content of anthocyanins and chromatic properties of wines. Different mechanical and electrical parameters (the distance between the drums, the frequency, and the voltage) have been tested in order to optimize the most effective PEF treatment so that the content of bioactive compounds such as anthocyanins be as high as possible, thus obtaining colour enhancement in the wine. In the case of the tests used, the results indicate that PEF treatment (with the characteristics: the distance between the drums of 2.5 mm, the voltage of 7 kV, the frequency of 178 Hz, and the pulse duration of 150 seconds) lead to a significant increase in the content of anthocyanins and to colour enhancement in both wines. The use of PEF in the winemaking industry is a promising technology that results in obtaining high quality wines.

The use of the high-frequency electromagnetic field (MW) and of the pulsed electric field (PEF) for the extraction of bioactive compounds from grapes

In recent years the uses of the high-frequency electromagnetic field (MW) and of the pulsed electric field (PEF) are studied as alternative methods in winemaking for better economic efficiency and to provide high quality products, rich in bioactive compounds. The aim of our paper was to compare the two methods, MW and PEF, in terms of their applicability for the extraction of bioactive compounds from two varieties of grapes (Pinot Noir and Merlot). We also determined the antioxidant capacity of the PEF or MW treated samples, and the results were processed using multivariate analysis. Finally, we noticed that both methods are effective for the extraction of bioactive compounds, but PEF treatments determine the highest rate of extraction of bioactive compounds.

Microwave-assisted extraction as a method of improving the quality of wines

ABSTRACT The aim of this paper is to study and compare the effect of microwave-assisted extraction (MW) on the content of bioactive compounds (total phenols, flavonoids, and monomeric anthocyanins), antioxidant capacity, chromatic parameters, and sensory properties of wines derived from three varieties of grapes (Muscat Ottonel, Pinot Noir, and Merlot). The applied MW treatment resulted in a more effective extraction of bioactive compounds from grapes that were also found in a large amount in the wine compared to the untreated (control) sample. The antioxidant capacity and colour intensity of the must and wine samples was much higher compared to the control sample. The influence of MW treatment depends on the variety of grapes treated. The results indicate that MW treatment is an appropriate method to produce white and red wine through increased extraction of bioactive compounds and implicitly colour enhancement.

The bioactive compounds, antioxidant capacity, and color intensity in must and wines derived from grapes processed by pulsed electric field

ABSTRACT The aim of this work was to study the effect of pulsed electric field (PEF) treatment on the content of bioactive compounds (total phenols, total flavonoids, monomeric anthocyanin content), antioxidant capacity, color intensity (CI), and sensory quality of wines derived from three varieties of grapes (Muscat Ottonel, Pinot Noir, and Merlot). PEF treatment resulted in an increase in all bioactive compounds, and consequently, an increase in their antioxidant capacity, which was evaluated by different methods. Applying PEF treatment to red grapes resulted in obtaining wines with higher CI compared to the control sample. For a better interpretation of the results and a proper discrimination of the samples in terms of the variety of grapes and PEF treatment, multivariate analyses, such as the principal component analysis, multivariate analysis of variance, and hierarchical cluster analysis, were applied.