Preliminary study of the effect of ultrasound on physicochemical properties of red wine

Abstract

Preliminary study of the effect of ultrasound on physicochemical properties of red wine Estudio preliminar sobre el efecto del ultrasonido en las propiedades fisicoquímicas del vino tinto Ultrasound is regarded as a potential alternative method for improving the quality of some wines. This study was initiated with the objective of evaluating the effects of ultrasound on some important physicochemical properties of red wine such as chromatic characteristics (CC), electrical conductivity (EC), pH, titratable acidity (TA), total phenolic compounds (TPCs) and DPPH (1,1-diphenyl-2-picryl-hydrazyl) free radical scavenging activity (DFRSA). The operational parameters assessed were ultrasound power, ultrasound frequency, exposure time and bath temperature. Results illustrated that there were significant changes in CC, EC and TPC while pH and TA hardly changed except for samples treated at high temperatures. DFRSA was correlated to TPC during ultrasonic treatment. Application of principal component analysis to the experimental data suggested that exposure time was the factor with the greatest ability to induce changes on wine. Results suggested that ultrasound may be applied to improve some physicochemical properties of red wine.Keywords: red wine; ultrasound; physicochemical properties; PCA; chromatic characteristicsEl ultrasonido se considera uno de los métodos alternativos potenciales para mejorar la calidad de algunos vinos. Se comenzó este estudio con el objetivo de evaluar los efectos del ultrasonido en algunas de la propiedades fisicoquímicas importantes del vino tinto como son: las características cromáticas (CC), la conductividad eléctrica (EC), el pH, la acidez (TA), los compuestos fenólicos totales (TPC) y el DPPH (1,1-difenil-2-picrilhidrazil) de actividad de eliminación de radicales libres (DFRSA). Los parámetros operacionales examinados fueron: la potencia de ultrasonido, la frecuencia de ultrasonido, el tiempo de exposición y la temperatura de baño. Los resultados ilustraron la existencia de cambios significativos en CC, EC y TPC, mientras que el pH y TA prácticamente no cambiaron excepto en las muestras tratadas con altas temperaturas. DFRSA tuvo correlación con TPC durante el tratamiento con ultrasonido. La aplicación de análisis de componentes principales a los datos experimentales sugirió que el tiempo de exposición era el factor con mayor habilidad para inducir cambios en el vino. Los resultados sugirieron que el ultrasonido podría aplicarse para mejorar algunas de las propiedades fisicoquímicas del vino tinto.

Preliminary study of the effects of ultrasound on red wine polyphenols

“…Recently, ultrasound effects on red wine physicochemical properties were investigated (Zhang, Shen, Fan, & García Martín, 2015). The authors reported that different conditions of ultrasonic treatment changed significantly the concentration of total phenolic compounds and the electrical conductivity.…”

Physicochemical properties and in-vitro antioxidant capacity of Semen Astragali Complanati wine

“…The values of L*, a* and b* of the wine are 85, 4 and 28, respectively, which is slightly different from those of the common grape wines that were tested in our lab (80, 20 and 8), especially for the values of a* and b* (Zhang, Shen, Fan, & García Martín, 2016). It may be attributed to the lower content of anthocyanins in the Semen Astragali Complanati.…”

“…In general, the color of grape juice and wine is an important attribute that is related to the visual appeal and quality and that is attributed to the free anthocyanins, principally as flavylium cation (red) and quinoidal anhydro-base (blue), anthocyanin self-association and copigmentation of anthocyanins with other phenols in wines. In addition, the content of tartaric esters is 60 mg/L, which is significantly lower than the content of 250 mg/L in grape wines; this result may be explained by the lower tartaric acid content in Semen Astragali Complanati and by the yeast strain and the conditions that were used for fermentation (López-Ramírez, Martín-del-Campo, Escalona-Buendí, García-Fajardo, & Estarrón-Espinosa, 2013;Zhang et al, 2016). The concentration and relative distribution of ester are usually influenced by the yeast variety and fermentation parameters, such as pH, temperature, oxygen levels, fatty acid or sterol levels (Sudheer Kumar, Varakumar, & Reddy, 2012).…”

Free radical generation induced by ultrasound in red wine and model wine: An EPR spin-trapping study

“…We do need the free radicals, which is easier to be generated by high power ultrasound, to accelerate aging and oxidation of wine [9]. But according to our results [24,27], higher ultrasonic power would lead the degradation of phenolic compounds in red wine, and these compounds are beneficial to health as well known by now. Besides that, Zheng [5] argued that ultrasonic conditions of 300 W could improve the maturation of wine.…”