Estudo do envelhecimento acelerado no aroma, cor e parâmetros físico-químicos de vinhos Tannat

In this work, different techniques were evaluated to achieve accelerated aging of the wine: ultrasound (US), gamma irradiation (RG) and high pressure (AP). The experimental conditions for each treatment were as follows: US, sequences of 30 and 60 minutes at 20 kHz; RG, three doses were analyzed (1, 3 and 6 kGy); for AP a constant pressure of 650 MPa was applied varying the application time (15, 30, 60 and 120 minutes). The wines were characterized by their basic physicochemical characteristics, their volatile profile (GC-MS) and color analysis (CIELAB). The same wine but without any treatment was used as a control. The results obtained showed that US treatment did not produce significant differences with respect to the control for all the conditions tested. For AP, significant differences were obtained with respect to the control in color (decrease in all the chromatic parameters) and content of volatile compounds (increase in the terpenes and esters contents). The GR treatment produced the greatest changes with respect to the control wine, with an increase in all the chromatic parameters with increasing radiation dose. The volatile profile showed an increase in 3-oxo-α-ionol, ho-diol and ethyl lactate content, all desirable changes during natural ageing.En este trabajo se evaluaron diferentes técnicas para lograr un envejecimiento acelerado del vino: ultrasonido (US), radiaciones gamma (RG) y altas presiones (AP). Las condiciones experimentales para cada tratamiento fueron: US, se aplicaron secuencias de 30 y 60 minutos a 20 kHz; RG, se analizaron tres dosis (1, 3 y 6 kGy); AP, se sometieron las muestras a una presión constante de 650 MPa variando el tiempo de aplicación (15, 30, 60 y 120 minutos). Los vinos fueron caracterizados por sus parámetros fisicoquímicos básicos, su perfil volátil (GC-MS) y el análisis de color (CIELAB). Se utilizó como testigo el mismo vino sin tratar. Los resultados mostraron que el tratamiento de US no produjo diferencias significativas respecto al control en ninguna de las condiciones ensayadas. Aplicando AP se obtuvieron diferencias significativas respecto al control en el color (disminución de todos los parámetros cromáticos) y en el contenido de compuestos volátiles (aumento del contenido de terpenos y esteres). El tratamiento GR produjo los mayores cambios respecto al vino control, con un incremento de todos los parámetros cromáticos al aumentar la dosis de radiación. Mientras que en el perfil volátil se observó un aumento del contenido de 3-oxo-α-ionol, ho-diol y lactato de etilo, todos cambios deseables durante el envejecimiento natural.Neste trabalho, foram avaliadas diferentes técnicas para conseguir um envelhecimento acelerado do vinho: ultra-som (US), radiação gama (GR) e alta pressão (HP). As condições experimentais para cada tratamento foram: US, sequências de 30 e 60 minutos a 20 kHz; RG, foram analisadas três doses (1, 3 e 6 kGy); para AP, foi aplicada uma pressão constante de 650 MPa variando o tempo de aplicação (15, 30, 60 e 120 minutos). Os vinhos caracterizavam-se por características fisicoquímicas básicas, perfil volátil (GC-MS) e análise de cor (CIELAB). O mesmo vinho não tratado foi utilizado como controlo. Os resultados mostraram que o tratamento dos EUA não produziu diferenças significativas no que diz respeito ao controlo em nenhuma das condições testadas. Quando o AP foi aplicado, foram obtidas diferenças significativas em relação ao controlo em cor (diminuição em todos os parâmetros de cor) e conteúdo de compostos voláteis (aumento em terpenos e ésteres). O tratamento GR produziu as maiores alterações em relação ao vinho de controlo, com um aumento de todos os parâmetros cromáticos, uma vez que a dose de radiação foi aumentada. Enquanto no perfil volátil, foi observado um aumento no teor de 3-oxo-α-ionol, ho-diol e lactato de etilo; todas alterações desejáveis durante o envelhecimento natural

Development of a Potential Functional Yogurt Using Bioactive Compounds Obtained from the By-Product of the Production of Tannat Red Wine

Tannat (Vitis vinifera cv. Tannat) grape pomace, which is mainly composed of peels and seeds, is an abundant by-product of the Uruguayan wine industry. Tannat skin from grape pomace is a sustainable source of bioactive compounds and dietary fiber. In previous studies, Tannat skin has shown antioxidant, antidiabetic, anti-obesity and anti-inflammatory activity, with the potential to prevent the development of chronic diseases. In this work, the encapsulation of bioactive compounds of an ethanolic extract derived from Tannat grape skin by microparticles of whey protein isolate (without and with enzymatic hydrolysis) and inulin (3:1) is studied for its application in yogurt as a potential functional food. Thus, it is proposed to evaluate the release of the bioactive compounds after digestion, for which an in vitro digestive simulation study was carried out simulating the conditions of the gastrointestinal tract. Among the most relevant results, the encapsulants showed increased total polyphenol content (TPC) and antioxidant capacity (p < 0.05) after in vitro digestive simulation. In addition, the different yogurt formulations showed increased (p < 0.05) TPC and antioxidant capacity after in vitro digestion, probably due to the release of bioactive peptides from milk proteins that are part of the yogurt. In conclusion, the antioxidant capacity shown after in vitro digestive simulation by the yogurts formulated with the spray drying encapsulated Tannat grape skin extract represent potential for its application in functional yogurts

Design of self-assembled TiO 2

Rational design and processing are critical to the fabrication of high performance architectures. Although the fabrication of titania nanotube (TN) array films has been studied extensively during the last decade, fabrication of ordered nanoporous titania structures at ambient conditions still remains a challenge. In this work, we report a method for the fabrication of hybrid TN/nanopore layers by altering the electrochemical conditions during titanium anodization. The electrochemical and photocatalytic properties of nanolayers at different stages of the transition from nanoporous TiO2 to nanotubular TiO2 structure were studied by different electrochemical characterization techniques