High power ultrasounds: A powerful, non-thermal and green technique for improving the phenolic extraction from grapes to must during red wine vinification

Wine color is one of the main organoleptic characteristics influencing its quality. It is of especial interest in red vinifications due to the economic resources that wineries have to invest for the extraction of the phenolic compounds. To increase this extraction, some chemical (maceration enzymes) or physical technologies (thermovinification, criomaceration, flash-expansion) can be applied. In this work, the results of the application of high power ultrasounds to the crushed grapes to increase the extraction of phenolic compounds are presented. Crushed grapes (400 kg) from the 2017 harvest were treated with ultrasound, and three different lengths of skin maceration period (2, 3 or 7 days) and the results were compared with a control vinification, where grapes were not subjected to any treatment and were skin macerated during 7 days. The wine chromatic characteristics and the individual phenolic compounds were followed during all the maceration period, at the end of alcoholic fermentation and after bottle storage. The wines made with ultrasound treated grapes presented differences with control wine, especially as regard color and total phenol and tannin content, the wines with three days of maceration time presenting similar chromatic characteristics than control wines with 7 days of maceration time

Reemplazo de la estabilización tartárica por frío en las bodegas: El uso de carboximetil celulosa, poliaspartato de potasio y resinas intercambiadoras de iones

El tratamiento de los vinos antes del embotellado para evitar la precipitación de las sales del ácido tartárico es un paso importante y común durante la producción del vino. La estabilización en frío es el tratamiento de estabilización más utilizado, y aunque ha demostrado ser efectiva, presenta algunas desventajas significativas. Estas son las razones por las cuales se están introduciendo otros productos y metodologías en las bodegas. Algunas de estas nuevas técnicas implican la reducción de la concentración de ácido tartárico y/o potasio en los vinos. Otras son técnicas aditivas y utilizan coloides protectores o inhibidores de la cristalización de las sales. En este estudio, se han tratado con carboximetilcelulosa, con poliaspartado de potasio y con resina de intercambio iónico vinos blancos, rosados y dos tipos diferentes de vinos tintos. Se estudiaron las características enológicas y cromáticas de los vinos y se evaluaron también sensorialmente. Los resultados indican que las características sensoriales y cromáticas se mantuvieron en los vinos (en comparación con un vino de control no tratado) con el uso de la carboximetilcelulosa y el poliaspartato, no detectándose diferencias en la mayoría de los casos en una prueba sensorial triangular en el caso de la carboximetilcelulosa y siendo los vinos tratados con poliaspartato de potasio evaluados positivamente

The effect of yeast on the anthocyanin characteristics of fermented model solutions

The sensory quality of red wines is basically determined by the colour, which depends on the amount and on the evolution of anthocyanins and other phenolic compounds extracting from the berries into the wine during wine-making. The anthocyanin-monomers are responsible for the development of the red colour, and their acylated derivatives provide stability for the colour of the wines. The anthocyanin profile of wines is affected by several factors: the grape variety, the conditions during wine-making, and also the yeast culture used for the fermentation. In our experiments a self-compiled model solution was fermented by spontaneous fermentation, as well as by four commercial yeasts under laboratory conditions. After fermentation total polyphenolics, anthocyanins, anthocyanin monomer profile, colour intensity, hue, and the ratio of polymeric anthocyanins were studied. Our results show that the spontaneous yeast fermentation resulted in a higher anthocyanin concentration in the fermented model solution, but the commercial yeast strains provided a more advantageous colour characteristic compared to the spontaneous fermentation. After the spontaneous fermentation less sediment was left than in the commercial yeast fermented samples

High power ultrasounds: A powerful, non-thermal and green technique for improving the phenolic extraction from grapes to must during red wine vinification

Wine color is one of the main organoleptic characteristics influencing its quality. It is of especial interest in red vinifications due to the economic resources that wineries have to invest for the extraction of the phenolic compounds. To increase this extraction, some chemical (maceration enzymes) or physical technologies (thermovinification, criomaceration, flash-expansion) can be applied. In this work, the results of the application of high power ultrasounds to the crushed grapes to increase the extraction of phenolic compounds are presented. Crushed grapes (400 kg) from the 2017 harvest were treated with ultrasound, and three different lengths of skin maceration period (2, 3 or 7 days) and the results were compared with a control vinification, where grapes were not subjected to any treatment and were skin macerated during 7 days. The wine chromatic characteristics and the individual phenolic compounds were followed during all the maceration period, at the end of alcoholic fermentation and after bottle storage. The wines made with ultrasound treated grapes presented differences with control wine, especially as regard color and total phenol and tannin content, the wines with three days of maceration time presenting similar chromatic characteristics than control wines with 7 days of maceration time

Reemplazo de la estabilización tartárica por frío en las bodegas: El uso de carboximetil celulosa, poliaspartato de potasio y resinas intercambiadoras de iones

El tratamiento de los vinos antes del embotellado para evitar la precipitación de las sales del ácido tartárico es un paso importante y común durante la producción del vino. La estabilización en frío es el tratamiento de estabilización más utilizado, y aunque ha demostrado ser efectiva, presenta algunas desventajas significativas. Estas son las razones por las cuales se están introduciendo otros productos y metodologías en las bodegas. Algunas de estas nuevas técnicas implican la reducción de la concentración de ácido tartárico y/o potasio en los vinos. Otras son técnicas aditivas y utilizan coloides protectores o inhibidores de la cristalización de las sales. En este estudio, se han tratado con carboximetilcelulosa, con poliaspartado de potasio y con resina de intercambio iónico vinos blancos, rosados y dos tipos diferentes de vinos tintos. Se estudiaron las características enológicas y cromáticas de los vinos y se evaluaron también sensorialmente. Los resultados indican que las características sensoriales y cromáticas se mantuvieron en los vinos (en comparación con un vino de control no tratado) con el uso de la carboximetilcelulosa y el poliaspartato, no detectándose diferencias en la mayoría de los casos en una prueba sensorial triangular en el caso de la carboximetilcelulosa y siendo los vinos tratados con poliaspartato de potasio evaluados positivamente