Composição volátil das uvas ao espumante da cv. Chardonnay em diferentes condições de manejo no sul de Minas Gerais (Brasil) / Volatile composition from grapes to sparkling wine of Chardonnay vine in different management conditions in southern of Minas Gerais (Brazil)

O aroma é um dos fatores mais importantes na determinação da qualidade e do caráter do vinho. Isso se deve à presença de compostos voláteis que estão associados às suas características organolépticas ou diferentes proporções entre estes compostos que podem ser influenciadas por fatores vitícolas (clima, solo, cultivar, manejo) e enológicos (maturação da uva, fermentação, tratamentos pósfermentativos). A região do sul de Minas Gerais vem se destacando na produção de espumantes de qualidade, e, nesse contexto, o presente trabalho teve como objetivo conhecer a influência do manejo da videira no desenvolvimento do aroma, da baga até o espumante, a fim de estabelecer associações com a qualidade do produto final. Os experimentos foram realizados com a cultivar Chardonnay em diferentes condições de manejo, em que foram avaliados clones, porta-enxertos, sistemas de condução e densidades de plantio. Foram analisados os compostos voláteis livres por HS-SPME/GC-MS das bagas, mostos, vinhos base e espumantes nas safras 2016, 2017 e 2018. O trabalho foi dividido em quatro partes para a apresentação dos resultados. A primeira consistiu em verificar a influência do material genético na composição volátil da cv. Chardonnay com os experimentos de clones e portaenxertos; a segunda parte avaliou a composição volátil do clone 809 até o espumante; a terceira, em analisar as vinificações dos diferentes sistemas de condução; e a quarta, em avaliar a evolução dos compostos voláteis da baga ao espumante e analisar os aromas que as densidades de plantio podem conferir ao espumante. As principais classes de compostos aromáticos identificados nas matrizes foram: C6-C9 aldeídos, álcoois superiores, aldeídos ramificados, benzenoides, monoterpenoides, norisoprenoides, sesquiterpenoides, cetonas e ácidos graxos. Os resultados mostraram que os clones e os porta-enxertos apresentaram perfis voláteis diferentes, indicando que a variabilidade entre os clones e que a enxertia têm influência no metabolismo da baga; o clone 809 apresenta maior abundância de compostos monoterpenoides, confirmando o seu caráter moscato, das uvas aos espumantes; os diferentes sistemas de condução e densidades de plantio alteram o metabolismo da14 baga, refletindo no perfil volátil dos espumantes nas safras estudadas. Dessa forma, os dados indicam que a composição volátil sofre influência do manejo da videira ao espumante

Aroma is one of the most important factors in determining the quality and character of wine. This is due to the presence of volatile compounds that are associated with their organoleptic characteristics or different proportions among these compounds that can be influenced by viticultural (climate, soil, cultivar, management) and oenological factors (grape maturation, fermentation, post fermentation treatments). The southern region of Minas Gerais has been standing out in the production of quality sparkling wines, and in this context, the purpose of the present work was to learn about the influence of grapevine management on the development of aroma, from berry to sparkling wine, in order to establish associations with the quality of the final product. The experiments were carried out with the Chardonnay cultivar under different management conditions, in which clones, rootstocks, trellising systems and planting densities were evaluated. The free volatile compounds by HS-SPME/GC-MS of the berries, musts, base and sparkling wines in the 2016, 2017 and 2018 harvests were analyzed. The work was divided into four parts in order to present the results. The first part consisted of verifying the influence of genetic material on the volatile composition of the cv. Chardonnay with the experiments on clones and rootstocks; the second part evaluated the volatile composition of clone 809 up to the sparkling wine; the third one part analyzed the vinification of the different trainig systems; and the fourth part evaluated the evolution of the volatile compounds from the berry to the sparkling wine and analyzed the aromas that the planting densities can confer to the sparkling wine. The main classes of aromatic compounds identified in the matrices were: C6-C9 aldehydes, higher alcohols, branched aldehydes, benzenoids, monoterpenoids, norisoprenoids, sesquiterpenoids, ketones and fatty acids. The results showed that the clones and the rootstocks have different volatile profiles, indicating that variability among clones and that grafting have great relevance to the berry secondary metabolism; the 809 clone presents a greater abundance of monoterpenoid compounds, confirming its muscat character, from grapes to sparkling wines; the different training systems and planting densities alter the berry´s metabolism, reflecting16 in the volatile profile of sparkling wines in the studied harvests. The data indicate that the volatile composition is influenced by the management of the berry to the sparkling wine

Physicochemical and sensory characteristics of fine sparkling red wines produced at different maceration lengths in the south of Brazil / Características físico-químicas e sensoriais de vinhos espumantes finos tintos produzidos a partir de diferentes períodos de maceração no sul do Brasil

Maceration is the step of the vinification process in which phenolic and aromatic compounds are transferred to wine. This study aimed at producing fine sparkling red wines by testing different grape varieties and maceration lengths. Grapes underwent maceration for 24 hours (Very Short Maceration ­ VSM) and for 48 hours (Short Maceration ­ SM). Sparkling wines were produced by the traditional method and analyses were carried out in the must, base wines and sparkling wines. Analyzes of minerals, volatile compounds and physicochemicals related to total soluble solids (TSS), Volatile Acidity (VA); Free Sulfur Dioxide (Free SO2); Total Sulfur Dioxide (Total SO2); Total Titratable Acidity (TTA); Fixed Acidity (FA); Hydrogenionic Potential (pH); Alcoholic Content (AC); Reduced Dry Extract (RDE); Total Tannins (TT); Total Anthocyanins (TA); Total Polyphenol Content (TPC); Total Color Intensity (TCI). In addition, during the tasting, a quantitative and descriptive record was distributed to the researchers to characterize the wines in relation to color, perlage, aroma, flavor, main descriptor of the aroma and main general adjective. The sparkling wines which had the best evaluations at different maceration lengths were the following: sparkling wine 100% Teroldego (SM) and sparkling wine 62.5% Teroldego, 18.75% Merlot and 18.75% Pinot (SM). Both short maceration (48 hours) and the Teroldego variety were the vinification parameters which provided the best olfactory-gustatory and color characteristics to the sparkling wines under study. All sparkling wines had enological potential to be vinified in red. Maturation and maceration processes under evaluation produced the typical freshness of sparkling wines and the desired red color.

A maceração é a etapa da vinificação na qual os compostos fenólicos e aromáticos são transferidos ao vinho. O objetivo deste trabalho foi produzir espumantes finos tintos testando a variedade de uva e a duração da maceração. As uvas sofreram maceração por 24 horas (Maceração Muito Curta - MMC) e por 48 horas (Maceração Curta - MC). Os espumantes foram produzidos com o método tradicional e as análises realizadas nos mostos, vinhos base e espumantes. Foram realizadas análises de minerais, de compostos voláteis e físico-químicas relacionadas a sólidos solúveis totais (SST), acidez volátil (AV), acidez total (AcT), dióxido de enxofre livre (SO2L) e total (SO2T), acidez fixa (AF), potencial hidrogeniônico (pH), teor alcoólico (TA), extrato seco (ES), extrato seco reduzido (ESR), índice de polifenóis totais (IPT), antocianinas totais (AT), taninos totais (TT) e intensidade total da cor (ITC). Além disso, durante a degustação, uma ficha quantitativa e descritiva foi distribuída aos pesquisadores para caracterizar os vinhos em relação à cor, perlage, aroma, sabor, principal descritor do aroma e principal adjetivo geral. Nas diferentes macerações, os espumantes que obtiveram melhores avaliações foram: 100% Teroldego (MC) e 62,5% Teroldego, 18,75% Merlot e 18,75% Pinot Noir (MC). Indicando que a maceração curta e a variedade Teroldego foram os parâmetros de vinificação que proporcionaram melhores características olfato-gustativas e de coloração aos espumantes estudados. Excetuando-se o espumante 100% Merlot (MC), todos demonstraram possuir potencial enológico para serem vinificados em tinto e as maturações e macerações testadas produziram o frescor característico dos espumantes e a coloração tinta desejada.

La escleroterapia con espuma es un método eficaz para el tratamiento de la insuficiencia venosa / Foam sclerotherapy is an effective method for the treatment of venous insufficiency

«La escleroterapia puede mucho más de lo que en general imaginamos. Teóricamente lo puede todo (Mollard 1994)». En esta reflexión, este cirujano vascular, intuye la potencialidad de los esclerosantes en la nueva forma farmacéutica acabada de nacer. La escleroterapia, procedimiento técnicamente ciego, no evolucionaba, permanecía durante décadas como complemento a la cirugía. No podía progresar porque estaba presa de limitaciones inherentes a la forma líquida de los productos utilizados que impiden hacer suyos los requerimientos básicos de la escleroterapia: a) Conocimiento de la concentración intravascular del esclerosante. b) Homogénea, extensa y manejable distribución sobre las paredes venosas. c) Control del tiempo de contacto esclerosante-endotelio. La clave de la escleroterapia se encierra en el control de la acción de los fármacos esclerosantes y este control se consigue con la forma farmacéutica de espuma inyectable; con ella la escleroterapia rápidamente evoluciona hasta alcanzar una nueva era

'Sclerotherapy can be much more than we generally imagine. Theoretically, it can be everything. (Mollard 1994)'. In this reflection, a vascular surgeon sensed the potentiality of sclerosing agents in the recently created new pharmaceutical form. Sclerotherapy, technically a blind procedure, did not evolve; it remained as a complement to surgery for years. It was unable to progress because it was a prisoner of the imitations adherent to the liquid form of the products used, which that impeded compliance with the basic requirements of sclerotherapy: a) Knowledge of the intravascular concentration of the sclerosing agent. b) Homogeneous, extensive, and manageable distribution of the venous walls. c) Temperature control of the sclerosing agent-endothelium contact. The key to sclerotherapy involves controlling the action of the sclerosing drugs, and this control is achieved in the pharmaceutical form of an injectable foam, and with this, sclerotherapy rapidly advanced until reaching this new era. Nowadays, different therapies are used in the treatment of varicose veins, including radiofrequency and laser ablation, stripping, surgery, echanical-chemical systems, steam, and glue, with very different outcomes. Sclerotherapy is a minimally invasive technique used for more than a hundred years, and useful for treating tiny little veins, until recently, in 1993, a pharmaceutical grade foam was developed that succeeded in treating large varicose veins, and is imitated by many others. The physical-chemical features of these foams vary considerably among themselves, depending on the production technique, concentration of sclerosing agent, types of gases used, gas/liquid proportion, type of gas/ size of bubble ratio, as well as varying in their safety and therapeutic use. The optimal liquid/gas proportion is obtained when there is sufficient liquid for the bubbles to be spherical and with the smallest diameter possible, but without introducing excess sclerosing liquid, which is described as kugelschaum (wet foam) or alternatively, it forms polyederschaum (dry foam). A series of experimental and theoretical studies have been conducted with the purpose of investigating the mechanical and rheological properties of the foams. However, to study its dynamic behaviour is a challenging theoretical problem, due to the complex interaction between the physical phenomena that occur in different longitudinal scales (that is to say, from the molecular to the macroscopic). And, in this interesting time of the evolution of the injection of drugs deposited over bubbles, is where we currently are

Control de las tasas de aireación y agitación en la producción de surfactina en un cultivo alimentado (fed-batch) en espuma desbordante con fermentación industrial / Control of agitation and aeration rates in the production of surfactin in foam overflowing fed-batch culture with industrial fermentation

Bacillus amyloliquefaciens fmb50 produces a high yield of surfactin, a lipopeptide-type biosurfactant that has been widely studied and has potential applications in many fields. A foam overflowing culture has been successfully used in the combined production-enrichment fermentation of surfactin. In this study, the agitation and aeration rates were found to have relationships with foam formation and surfactin enrichment. A maximum surfactin concentration of 4.7 g/l of foam was obtained after 21 h of culture with an agitation rate of 150 rpm and an aeration rate of 1 vvm in fed-batch culture. By controlling the foam overflow rate (f out) of a fed-batch culture, surfactin concentration in the foam was continuously maintained above 4 g/l.

Bacillus amyloliquefaciens fmb50 produce gran cantidad de surfactina, un biosurfactante de tipo lipopeptídico que ha sido objeto de estudios pormenorizados y tiene aplicaciones en muchos campos. El cultivo en espuma desbordante se ha utilizado con éxito en la fermentación combinada de producción-enriquecimiento de surfactina. En este estudio, se halló que las tasas de aireación y agitación tienen relación con la formación de espuma y el enriquecimiento de la surfactina. Se obtuvo una concentración máxima de surfactina de 4,7 g/l de espuma después de 21 h de cultivo con una tasa de agitación de 150 rpm y una tasa de aireación de 1 vvm en un cultivo alimentado (fed-batch). Al controlar la tasa de espuma desbordante (f out) de un cultivo fed-batch, la concentración de surfactina en la espuma se mantuvo continua por encima de 4 g/l.

Physical characterization of freeze-dried foam prepared from Aloe Vera gel and guar gum / Caracterización de espumas liofilizadas preparadas a partir de gel de Aloe vera y goma guar

Background: Foams are colloidal dispersions of a gas suspended in a dispersing phase, which consisting of a semi-freeze-dried or viscous liquid phase. The physical properties of food foams are the result of the bubble characteristics and their spatial arrangement. Objectives: The aim of this work was to obtain foams of A. vera gel and guar gum and describe the changes in their physical properties and microstructure during freeze-drying using the fractal dimension concept and image analysis techniques. Methods: The porosity, density, and volume expansion factor of the fresh foams that were based on the A. vera foams were determined. The kinetics of foam texture, color, porosity and microstructure of the freeze-dried foams were obtained. The fractal texture dimension of surface (FDSDBC) and microstructure (FDESEM) of the foams were determined as indicators of structural changes after freeze-drying. The guar gum concentrations used to obtain the A. vera prefoam were expressed in w/w as F1 (control sample without gum), F2 (2%), F3 (4%) and F4 (6%). Results: We obtained stable freeze-dried foams of Aloe vera gel and guar gum. The porosity, density and volume expansion factor of the fresh and freeze-dried foams were affected by the addition of the guar gum. Changes in the topology of the freeze-dried foam surface during the drying process resulted in a high rugosity compared with the original smooth surface. The microstructure of the dried foam samples suggested a relationship between the gum concentration of the prefoam A. vera gel mixture and the physical properties before and after freeze-drying, such as an increase in the microstructural alterations and surface roughness during freeze-drying. The roughness of the freeze-dried foam surface, described by the FDSDBC represented the macroscopic physical changes of the samples and correlated with the changes in the foam microstructure, which were described by the fractal dimension of the Environmental Scanning Electron Microscopy ESEM microphotographs (FDESEM). Conclusions: The digital analysis of the structure and porosity of the freeze-dried foam can be used to quantify the effect of gum concentrations on the morphological features and physical properties of foams during freeze-drying.

Antecedentes: Las espumas son dispersiones coloidales de un gas en una fase líquida viscosa. Las propiedades físicas de las espumas alimentarias son el resultado de las características de sus burbujas y su disposición espacial. Objetivos: El objetivo de este trabajo fue obtener espumas de gel de A. vera y goma guar y describir los cambios en sus propiedades físicas y su microestructura durante el secado por liofilización utilizando el concepto de dimensión fractal y las técnicas de análisis de imagen. Métodos: Se determinó la porosidad, densidad, factor de expansión volumétrico de las espumas frescas de A. vera. Así como la cinética de liofilización, textura, isotermas de sorción, color, porosidad y la microestructura las espumas liofilizadas. La dimensión fractal de la textura (FDSDBC) y microestructural (FDESEM) de las espumas de gel de A. vera y goma guar liofilizadas se determinó como un indicador de los cambios estructurales después de la liofilización. Las concentraciones de goma de guar utilizados para obtener la solución de clara de huevo preespuma se expresaron en w/w como F1 (muestra de control sin goma), F2 (2%), F3 (4%) y F4 (6%). Resultados: Fue posible obtener espumas liofilizadas estables de gel de A. vera y goma guar. La porosidad, densidad, factor de expansión volumétrico de las espumas se vieron afectadas con la adición de goma guar. Los cambios en la topología de la superficie de la espuma liofilizada durante todo el proceso de secado dieron lugar a alta rugosidad en comparación con la superficie lisa original. La microestructura de las muestras de espuma secas sugirió una relación entre la concentración de goma de las espumas de A. vera y las propiedades físicas antes y después de la liofilización como un aumento en las alteraciones microestructurales y rugosidad de la superficie durante el secado por congelación. La rugosidad de la superficie de la espuma liofilizada, se describió por la relación FDSDBC que representa los cambios físicos macroscópicos de las muestras y se correlacionó con los cambios en la microestructura de espuma, que fueron descritos por la dimensión fractal de las micrografías ESEM (FDESEM). Conclusiones: El análisis digital de la estructura y la porosidad de la espuma liofilizada se puede utilizar para cuantificar el efecto de las concentraciones de goma guar en las características morfológicas de las espumas durante el secado por congelación.

Proteins influencing foam formation in wine and beer: the role of yeast

This review focuses on the role of proteins in the production and maintenance of foam in both sparkling wines and beer. The quality of the foam in beer but especially in sparkling wines depends, among other factors, on the presence of mannoproteins released from the yeast cell walls during autolysis. These proteins are hydrophobic, highly glycosylated, and their molecular masses range from 10 to 200 kDa-characteristics that allow mannoproteins to surround and thus stabilize the gas bubbles of the foam. Both the production and stabilization of foam also depend on other proteins. In wine, these include grape-derived proteins such as vacuolar invertase; in beer, barley-derived proteins, such as LTP1, protein Z, and hordein-derived polypeptides, are even more important in this respect than mannoproteins (AU)

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Evaluation of foam properties of saponin from Ilex paraguariensis A. St. Hil. (Aquifoliaceae) fruits

Saponins are natural compounds able to form abundant foam, a desirable quality required in some chemical, foods, cosmetic and pharmaceutical processes. Ilex paraguariensis A. St. Hil. (Aquifoliaceae) known as mate, is a South American widely cultivated specie due to the preparation of a tea-like beverage from its leaves. Moreover, its green fruits are a rich source of non-toxic and very low haemolytic saponins. In this study, mate saponin fraction (MSF) was evaluated as a foam former, focusing on its foamability, foam lifetime, and film drainage in the presence of different electrolytes (ionic strength I = 0.024 M). Sodium dodecyl sulphate (SDS) and polysorbate 80 (Poly-80) were used as reference surfactants. The critical micelle concentration (CMC), the minimum attainable surface tension (γCMC), surface excess concentration (Γ) and cross-section molecular surface (A) values of MSF were comparable to those of Poly-80. The foamability of MSF and both reference surfactants was equivalent. The addition of MgCl2 resulted in a negative effect on MSF foamability. The salts NaCl, KBr, and KNO3 exhibited a negative influence on MSF foam lifetime. Similar behavior was observed for MSF film drainage (order of activity: Na2HPO4 > MgCl2 ≈ NaCl ≈ KNO3 > KBr), where a primary fast film drainage rate was followed by film thinning stabilization after around 5 min. The behavior described above seems to be uncorrelated to the solutions' zeta potential.

As saponinas são compostos naturais capazes de formar espuma abundante, qualidade desejável exigida em alguns processos químicos, alimentícios, cosméticos e farmacêuticos. Ilex paraguariensis A. St. Hil. (Aquifoliaceae), mais conhecida como mate, é uma espécie largamente cultivada devido ao consumo do chimarrão. Além disso, seus frutos verdes representam uma fonte rica de saponinas pouco tóxicas e pouco hemolíticas. Nesse trabalho avaliou-se a fração de saponinas de mate (MSF) como formadora de espuma, com ênfase na espumabilidade, permanência da espuma e drenagem do filme na presença de diferentes eletrólitos (I = 0,024 M). Dodecil sulfato de sódio (SDS) e polissorbato 80 (Poly-80) foram utilizados como tensoativos-referência. Os valores de concentração micelar crítica (CMC), tensão superficial na CMC (γCMC), concentração de excesso de superfície (Γ) e área do grupamento polar na interface (A) referente à MSF foram comparáveis ao Poly-80. A espumabilidade da MSF e de ambos os tensoativos-referência foram equivalentes. A adição de MgCl2 resultou em um efeito negativo sobre a espumabilidade de MSF. Os sais NaCl, KBr e KNO3 tiveram influência negativa sobre a estabilidade da espuma. Em relação à drenagem do filme de MSF, após 60 min. seguiu-se a ordem Na2HPO4 > MgCl2 ≈ NaCl ≈ KNO3 > KBr, caracterizando uma drenagem inicial acelerada seguida pelo equilíbrio hidrodinâmico do filme após 5 min. O comportamento observado parece não estar relacionado com o potencial zeta das soluções.

Crosectomía y escleroterapia con espuna en el tratamiento del reflujo de la unión safenofemoral: una alternativa terapéutica mínimamente invasiva / Crosectomy and foam sclerotherapy in the treatment of the saphenophemoral junction reflux: a minimally invasive therapeutic alternative

Evaluar la eficacia y las ventajas de la crosectomía y escleroterapia con espuma en el tratamiento del reflujo de la unión safenofemoral y compararla con la safenectomia convencional. Se trata de un estudio descriptivo, prospectivo, de una muestra seleccionada de casos, conformado por treinta y seis pacientes con enfermedad varicosa producto de reflujo de la unión safenofemoral que acudieron a la consulta del Servicio de Cirugía III del Hospital Universitario de Caracas en el período comprendido entre octubre del 2005 y octubre del 2006. Se realizó crosectomía y escleroterapia con espuma de etoxiesclerol en dieciocho casos y safenectomía convencional en los dieciocho casos restantes. Para la técnica descrita, el tiempo quirúrgico promedio fue de 30 minutos; no se prsentaron complicaciones intraoperatorias. El tiempo promedio de hospitalización fue de un día, con un reintegro a las actividades cotidianas a la segunda semana en todos los casos y una elevada tasa de satisfacción (94,4 por ciento). En el seguimiento durante un período de tres a doce meses no se encontraron recurrencias. Se reportó un caso de hiperpigmentación como única complicación postoperatoria asociada al procedimiento. Se demostró beneficio con respecto a la safenectomía convencional en cuanto a tasa de complicaciones postoperatorias (5,5 por ciento vs 33,3 por ciento, p<0,05). La crosectomía y esclerosis con espuma es una técnica factible, con elevada tasa de éxito, que ofrece las ventajas del tratamiento mínimamente invasivo sin la necesidad de requerir en quirófano de equipos de alto costo, adecuándose de esta manera a centros hospitalarios de menos recursos.