Microwave irradiation: impacts on physicochemical properties of red wine

Abstract

Microwave irradiation is considered as a potential alternative technology for promoting the progress of wine aging. The effects of microwave irradiation on some important physicochemical properties of young Cabernet Sauvignon dry red wine were studied. The results indicated that there were significant changes in total phenolic compounds (TPC), total monomeric anthocyanin (TMA), titratable acidity (TA), and DPPH-free radical scavenging activity (DFRSA), while pH and electrical conductivity (EC) hardly changed. DFRSA was correlated to TPC, TMA, and TA during microwave treatment. The changing trend of chromatic characteristics (CC), which induced by microwave irradiation, was consistent with that of aging red wine. The results of principal component analysis showed that there was a big difference between the untreated red wine and the treated red wine under different microwave conditions. The results suggested that microwave technology could change some physicochemical properties of red wine and promote the aging of red wine. Irradiación con microondas: impactos en las propiedades fisicoquímicas del vino tinto RESUMEN Se considera que la irradiación con microondas es una tecnología alternativa potencial para promover el proceso de añejamiento del vino. Con esta premisa se estudiaron los efectos de la irradiación por microondas en algunas propiedades fisicoquímicas importantes del vino tinto seco joven Cabernet Sauvignon. Los resultados obtenidos indicaron que se produjeron cambios significativos en los compuestos fenólicos totales (TPC), la antocianina monomérica total (TMA), la acidez valorable (TA) y la actividad de eliminación de radicales libres del DPPH (DFRSA), mientras que el pH y la conductividad eléctrica (EC) apenas se modificaron. Se constató que durante el tratamiento con microondas la DFRSA se correlacionó con los TPC, la TMA y la TA. La tendencia de cambio de las características cromáticas (CC), inducida por la irradiación con microondas, es coherente con la del añejamiento del vino tinto. Los resultados del análisis de los componentes principales dieron cuenta de que, bajo diferentes condiciones de microondas, existe una gran diferencia entre el vino tinto sin tratar y el vino tinto tratado. En este sentido apuntan a que la tecnología de microondas podría alterar algunas propiedades fisicoquímicas del vino tinto, promoviendo de esta forma su añejamiento.

Microwave‐induced free radicals production in red wine and model wine by electron paramagnetic resonance spin trapping

“…Free radicals were essential in the process of accelerated aging and oxidation of wine, and these free radicals were easier to be caused with high microwave power (Yuan, Wang, Wang, et al., 2020). But based on our results (Yuan, Wang, Chen, et al, 2020), higher microwave power could lead to degradation of phenolic compounds and decrease of antioxidant activity in red wine, phenolic compounds are focused for the reason of more health‐promotion activity in red wine, and play an essential role of wine because they are responsible for certain organoleptic properties, including aroma, color, flavor, bitterness, and astringency (Garrido & Borges, 2013). To avoid unnecessary loss of phenolic compounds and save more energy, low power should be selected in the aging process of red wine.…”

“…The initial stage of microwave treatment was the production and accumulation of 1-hydroxyethyl free radicals in model wine, so the intensity of free radicals produced in model wine increased significantly from 3 to 10 min. The reason for the rapid increase of free radicals was that there was potential degradation of the active compounds in the solution under microwave irradiation, and the degradation rate of active compounds increased with the extension of microwave treatment time (Yuan, Wang, Chen, et al, 2020). Catechin in model wine can scavenge free radicals, and the partial degradation of catechin resulted in the reduction of free radicals scavenging activity.…”

Microwave Irradiation: Effects on the Change of Colour Characteristics and Main Phenolic Compounds of Cabernet Gernischt Dry Red Wine during Storage

“…The determination of TPC was performed with Folin-Ciocalteu colorimetry [ 16 ], 15 μL red wine sample was added to the solution. Gallic acid equivalent per liter of red wine represented the result.…”

“…Our laboratory conducted a preliminary studies on the change of the physicochemical characteristics of wine after a short period of microwave treatment [ 16 ], content change and degradation phenomena of phenolic compounds caused by microwaves [ 17 ], 1-hydroxyethyl free radicals induced by microwave [ 9 ], and the change of properties and activities of PPO effected by microwaves in the grape maceration stage [ 18 ]. As far as we know, the dynamic changes in the colour, main anthocyanins, and phenolic compounds in red wine under microwave irradiation during storage and aging have not been reported.…”

Ultrasonic-assisted Extraction, Purification, Antioxidant and Antibacterial Activity of Polysaccharide from <i>Cornus officinalis</i> Leaves

“…According to the method of Yuan [17]: 1.0 mL polysaccharide solution was taken, adding 4 mL 0.004% DPPH solution, and mixed evenly. Then, it was standing in the dark for 30 min.…”