Efecto de la variación de pH, contenido metálico y uso de resinas de intercambio catiónico en el color de un vino tinto durante su oxidación

56 p.En esta memoria de título se realizó un estudio para determinar el contenido e influencia de metales (Hierro; Fe y Cobre; Cu), oxígeno y fenoles en la variación del color de un vino tinto. El trabajo se realizó bajo condiciones variables de pH, contenido metálico y uso de resinas de intercambio catiónico (RIC). Los tratamientos consistieron en la modificación de los niveles de pH, contenido metálico y porcentaje de vino tratado por RIC, con dos tiempos de medición: a los 3 y 34 días de montado el estudio. Para determinar la concentración de metales (mg/L) se utilizó la técnica de Espectroscopía de Absorción Atómica (AAS) que mediante la absorción de luz de cada metal (previa curva de calibración) permitió cuantificar el contenido de los metales Fe y Cu. Para esta determinación sólo se consideró la medición a los 34 días de montado el estudio (tiempo final). La determinación de oxígeno disuelto se realizó a través de un analizador de oxígeno “Nomasense” el cual bajo la técnica de oxiluminiscencia cuantificó de manera directa y no invasiva el contenido de oxígeno disuelto en el vino. La cuantificación de fenoles se hizo a través del método de Folin-Ciocalteau. Finalmente, las variaciones de color se determinaron a través de la absorbancia del vino en diferentes longitudes de onda características del vino tinto: 520, 420 y 620 nm. En cuanto a los resultados, es posible afirmar que el uso de RIC disminuye el contenido metálico en vinos, principalmente hierro, ya que el cobre no se ve afectado por esta técnica. Al existir un menor contenido metálico en los vinos tratados por RIC, el contenido de oxígeno disuelto vario entre los tratamientos. Adicionalmente a esto, la variación de oxígeno inicial versus final aumentó a medida que aumentaba el pH y contenido fenólico. En cuanto al contenido fenólico, este disminuyó a medida que aumentó el contenido de metales, oxígeno y pH del medio. No fue posible determinar la influencia del pH con exactitud ya que el tratamiento con mayor oxígeno y contenido metálico pero menor pH fue el que presentó mayor pérdida de contenido fenólico entre el tiempo inicial y final. Por otra parte, el color del vino se vio fuertemente afectado por reacciones de oxidación y/o combinación de fenoles u otros compuestos del vino. Con el paso del tiempo, el vino sufrió la pérdida de su color rojo intenso, pasando a tonalidades rojo teja o con tendencias al anaranjado. En conclusión, el vino se vio afectado por la variación de pH, presencia de metales y uso de RIC./ABSTRACT:In this work, a study was carried out to determine the content and influence of metals (iron, Fe and Copper, Cu), oxygen and phenols in the color variation of a red wine. The study was conducted under variable conditions of pH, metal content, and the use of cation exchange resins (CER). The treatments consisted in the modification of the pH levels, metallic content and percentage of wine treated by CER, measured at two different time points: 3 and 34 days after starting the experiment. In order to determine the concentration of metals (mg/L) the Atomic Absorption Spectroscopy (AAS) technique was used to quantify the content of Fe and Cu metals by means of the absorption of light from each metal (previous calibration curve). For this determination, only the measurement was considered at 34 days of the study (final time). The determination of dissolved oxygen was done through a "Nomasense" oxygen analyzer which under the oxiluminescence technique directly and non-invasively quantified the oxygen content dissolved in the wine. The quantification of phenols was done through the method of Folin-Ciocalteau who postulated an absorbance at 765 nm according to a preparation of the samples based on gallic acid. Finally, the color variations were determined through the absorbance of the wine at different wavelengths characteristic of the red wine: 520, 420 and 620 nm. Regarding the results, it is possible to affirm that the use of CER decreases the metallic content in wines, mainly iron, since the copper is not affected by this technique. When there was a lower metallic content in the wines treated by CER, the dissolved oxygen content behaved differently to the wines with the highest percentage of control wine, increasing its content in the first and decreasing in the second, in addition to this, the variation of initial versus final oxygen increased as pH and phenolic content increased. As for the phenolic content, this decreased as the metal content, oxygen and pH of the medium increased. The influence of the pH was not possible to determine with accuracy since the treatment with greater oxygen and metallic content but lower pH was the one that presented greater loss of phenolic content between the initial and final time. On the other hand, the color of the wine was strongly affected by oxidation reactions and /or combination of phenols or other wine compounds. With the passage of time the wine suffered the loss of its intense red color and passing to shades red tile or tendencies to orange. In conclusion, the wine is affected by the variation of pH, presence of metals and the use of CER, as well as the implementation of this last technique affects the content of metals and decreases the pH of the wine

Determinación y cuantificación de cationes (Ca, Mg, K, Na, Mn, Cu, Fe y Zn) en jugos y néctares envasados de producción chilena mediante espectrometría de absorción atómica

53 p.Ciento dieciséis muestras de jugos y néctares de producción chilena, provenientes de 6 regiones del país (IV, V, RM, VI, VII y XIV), además de 10 muestras de producción extranjera (Argentina, México y Estados Unidos) fueron analizadas mediante espectrometría de absorción atómica de llama (FAAS) para determinar su contenido de elementos metálicos (Ca, MG, K, Na, Mn, Cu, Fe y Zn). Los resultados obtenidos fueron analizados mediante un análisis de varianza, ANDEVA, para comparar las muestras de acuerdo a su origen (nacionalidad), región de producción, tipo de fruta declarada en la etiqueta y clasificación general como jugo o néctar. De esta misma forma se realizó un análisis de componentes principales (PCA) con la finalidad de discriminar los jugos y néctares bajo los mismos parámetros recién mencionados. Las concentraciones de los cationes en estudio resultaron dentro de los rangos óptimos para la ingesta humana declarados por la “Food and Drug Administration” FDA (EE.UU). El elemento metálicos potasio (K) fue el que presentó una mayor concentración media para jugos y néctares (1352,08 mg/L y 407,07 mg/L respectivamente). Por el contrario, el catión zinc (Zn) presentó la menor concentración media 0,50 mg/L para jugos, mientras que para néctares, este correspondió al catión cobre (Cu) 0,54 mg/L. Por otra parte, el análisis de componentes principales logró discriminar los jugos y néctares de acuerdo al país de origen y la región de producción, pero en el caso de la clasificación por tipo de producto (jugo o néctar), y el tipo de fruta declarado en la etiqueta, el contenido de metales no fue discriminante./ABSTRACT:One hundred and sixteen samples of Chilean juices and nectars, originating from 6 different regions (IV, V, RM, VI, VII and XIV), plus 10 foreign samples (Argentina, Mexico and United States) were analyzed by flame atomic absorption spectrometry (FAAS), to determine the content of metallic elements (Ca, Mg, K, Na, Mn, Cu, Fe and Zn). The results were analyzed by analysis of variance, ANOVA, to compare samples according their origin (nationality), region of production, type of fruit declared on the label and general classification as juice or nectar. Similarly, the samples were analyzed by principal components (PCA) with the purpose of discriminating juices and nectars under the same variables already mentioned. The concentrations of the cations in the study were within the ideal ranges for human intake as declared by the FOOD and Drug Administration, FDA (U.S.A). The metallic element potassium (K) was the one showing the highest average concentration for juices and nectars (1352,03 mg/L and 407,07 mg/L respectively). On the contrary, the cation zinc (Zn) showed the lowest average concentration for juices 0,50 mg/L, whereas in nectars the cation copper (Cu) had an average of 0,54 mg/L. Moreover, the results of the principal component analysis of juices and nectars allowed the separation of samples according to country and region of production. However, the classification based on type of product (juice or nectar) and fruit declared on the label, was not decisive

An Approach to Early Detection of Metabolic Syndrome through Non-Invasive Methods in Obese Children

Background: Metabolic Syndrome (MetS) has a high prevalence in children, and its presence increases in those with a high BMI. This fact confirms the need for early detection to avoid the development of other comorbidities. Non-invasive variables are presented as a cost-effective and easy to apply alternative in any clinical setting. Aim: To propose a non-invasive method for the early diagnosis of MetS in overweight and obese Chilean children. Methods: We conducted a cross-sectional study on 221 children aged 6 to 11 years. We carried out multivariate logistic regressions, receiver operating characteristic curves, and discriminant analysis to determine the predictive capacity of non-invasive variables. The proposed new method for early detection of MetS is based on clinical decision trees. Results: The prevalence of MetS was 26.7%. The area under the curve for the BMI and waist circumference was 0.827 and 0.808, respectively. Two decision trees were calculated: the first included blood pressure (≥104.5/69 mmHg), BMI (≥23.5 Kg/m2) and WHtR (≥0.55); the second used BMI (≥23.5 Kg/m2) and WHtR (≥0.55), with validity index of 74.7% and 80.5%, respectively. Conclusions: Early detection of MetS is possible through non-invasive methods in overweight and obese children. Two models (Clinical decision trees) based on anthropometric (non-invasive) variables with acceptable validity indexes have been presented. Clinical decision trees can be applied in different clinical and non-clinical settings, adapting to the tools available, being an economical and easy to measurement option. These methods reduce the use of blood tests to those patients who require confirmation

Evaluación del efecto de dos niveles de pH con dos condiciones iniciales de oxígeno en el contenido de compuestos fenólicos y sulfitos en vino cabernet sauvignon

52 p.Los compuestos fenólicos le otorgan variadas características organolépticas al vino tinto y son los principales reactantes que se oxidan en presencia de oxígeno generando una serie de reacciones químicas que pueden deteriorar su calidad. En este estudio se evaluaron los efectos de dos niveles de pH (3,5 y 4,0) y condición inicial de oxígeno (con aireación inicial y desplazamiento de oxígeno con gas nitrógeno) en el contenido de compuestos fenólicos y sulfitos en un vino tinto Cabernet Sauvignon. Los efectos de dichos tratamientos se evaluaron a partir de las determinaciones de consumo de anhídrido sulfuroso libre y total mediante el método de Ripper, y variaciones en la concentración de compuestos fenólicos mediante los métodos de Folin Ciocalteu y precipitación de proteínas. En cuanto al contenido de sulfitos, los tratamientos con pH alto presentaron una disminución más acelerada de su concentración. Por su parte, los resultados de compuestos fenólicos no presentaron diferencias significativas probablemente debido al corto tiempo en que se realizaron las mediciones.Bajo las condiciones de este estudio, no se puede concluir que los ajustes de pH y condición inicial de oxígeno fueron determinantes en la evolución del contenido de anhídrido sulfuroso libre y total, ni en el contenido y composición de los compuestos fenólicos medidos./ABSTRACT :Phenolic compounds provide several organoleptic characteristics to red wines and are the main reactants that protect the quality of wines against oxygen and oxidations.This study evaluated the effects of two pH levels (3.5 to 4.0) and initial oxygen condition (initial aeration and oxygen displacement with nitrogen gas) on the content of phenolic compounds and sulfites in red wine Cabernet Sauvignon. The effects of these treatments were evaluated following the content of free and total sulfites by means of the Ripper method, and phenolic compounds by the Folin Ciocalteu and protein precipitation assays. As for the content of sulfites, the high pH treatments showed a faster decrease of its concentration. On the other hand, the results of phenolic compounds were not significantly different, probably due to the short time in which measurements were made.Under the conditions used in this study, it can not be concluded that the pH adjustments and the initial condition of oxygen exposure used were crucial in the evolution of the content of free and total sulfur dioxide, and the content and composition of phenolic compounds analyzed

Consumo de oxígeno en soluciones hidro-alcoholicas bajo diferentes concentraciones fenólicas y niveles de PH

34 p.Para esta memoria de título, se realizó un estudio para determinar el tiempo que demora en consumirse el oxígeno disuelto (ppm) en soluciones modelo de vino bajo condiciones variables de pH y concentración fenólica (g/L ácido gálico). Los tratamientos consistieron en la modificación de los niveles de pH (3 y 4) y concentración fenólica 0,5; 1,0 y 2,0 g/L de ácido gálico en las soluciones modelo. Para determinar la concentración de oxígeno disuelto (ppm) se ocupó el medidor de oxígeno Noma-Sense, el que mediante una sonda de oxluminiscencia y un sensor de oxígeno disuelto ubicado dentro de la botella, permite determinar la cantidad de oxígeno disuelto presente en las soluciones modelo de vino de forma no invasiva. Las mediciones se realizaron cada 4 a 5 horas a pH 3 y cada 1-2 horas a pH 4.En cuanto a la variable concentración fenólica, las soluciones modelo a pH 3 que contienen 1,0 g/L- 2,0 g/L demoran entre un 25% a un 29% menos de tiempo (horas) en consumir el oxígeno disuelto cuando se comparan con las soluciones con 0,5 g/L. Las soluciones modelo a pH 4 que contienen de 1,0 g/L- 2,0 g/L demoran un 65% a un 78% menos de tiempo (horas) en consumir el oxígeno disuelto cuando se comparan con las soluciones que contienen 0,5 g/L. En cuanto a la variable pH, las soluciones a pH 4 demoran un 41% menos de tiempo (horas) que las soluciones a pH 3 en consumir el oxígeno disuelto cuando contienen 0,5 g/L de ácido gálico. Las soluciones modelo a pH 4 con 1,0 g/L de ácido gálico demoran un 65% menos de tiempo que las soluciones con a pH 3 con la misma concentración fenólica. Finalmente, las soluciones a pH 4 con 2,0 g/L demoran un 78% menos de tiempo que las soluciones a pH 3 con igual concentración fenólica./ABSTRACT; The goal of this study was made to determine the time that it takes to consume a given amount of dissolved oxygen (ppm) in model wine solutions under differents pH levels and phenolic concentrations (g / L gallic acid). The treatments consisted in two pH levels (3 and 4) and three phenolic concentration 0.5, 1.0 and 2.0 g / L of gallic acid in wine model solutions. A Noma Sense oxygen meter was used to determine the concentration of the dissolved oxygen (ppm). This meter works with the oxyluminiscense technique in a non invasive way, preventing oxygen contamination of the sample. Measurements were made every 4 to 5 hours at pH 3 and every 1-2 hours at pH 4. The results of the phenolic concentration variable showed that the pH 3 wine model solutions that contains 1.0 g/L- 2.0 g / L took between 25% to 29% less time (hours) than the solutions that contain 0.5 g/L in the oxygen consumption. At pH 4, the solutions that contain 1.0 g/L- 2.0 g / L took a 65% to 78% less time (hours) to consume the dissolved oxygen when compared to the solutions with 0.5 g / L. The results of the pH variable indicated that the solutions at pH 4 took 41% less time (hours) than the solutions at pH 3 in consume the dissolved oxygen when they contain 0.5 g / L of gallic acid. Model solutions at pH 4 with 1.0 g / L of gallic acid took 65% less time than the solutions to pH 3 with the same phenolic concentration in the oxygen consumption. Finally, the pH 4 solutions with 2.0 g / L of phenol took 78% less time than the pH 3 solutions with equal phenolic concentration in consume the dissolved oxygen

Association between the FTO SNP rs9939609 and Metabolic Syndrome in Chilean Children

The increasing prevalence of obesity in children has raised the incidence of Metabolic Syndrome (MetS) in this age group. Given the short- and long-term health impact of MetS, it is essential to prevent its onset by detecting its main triggers. Besides, genetic factors play an essential role in influencing which individuals within a population are most likely to develop obesity in response to a particular environment. In this regard, a common variation in the FTO gene is reproducibly associated with BMI and obesity from childhood and the genetic load has been linked to several cardiovascular risk factors, highlighting the FTO single nucleotide polymorphism (SNP) rs9939609. Therefore, this study aimed to establish the relationship between the FTO SNP rs9939609 and MetS. Methods: A cross-sectional study was carried out on 220 children from the Biobío region (Chile). MetS diagnosis was established through the modified Cook criteria, using prevalence ratios, COR curves, and linear regressions to determine its association with MetS and its components. Results: The prevalence of MetS was significantly increased among carriers of the risk allele (A): TT, 20.2%; TA, 25.4%; AA, 44.7% (p = 0.006). Also, the presence of A was associated with altered MetS-related variables. Conclusions: The FTO SNP rs9939609 was associated with a raised prevalence of MetS among A allele carriers, and was higher in the homozygous genotype (AA)

Evaluación del contenido de dióxido de azufre y compuestos fenólicos en vino Sauvignon Blanc a dos niveles de Ph y dos condiciones iniciales de oxígeno

44 P.El vino blanco posee una baja concentración de compuestos fenólicos, en comparación a los vinos tintos, por lo que su capacidad de soportar exposiciones frecuentes, o rolongadas al aire, sin mostrar signos de oxidación, es limitada. En el siguiente estudio, se evaluó el efecto de dos niveles de pH (3,0 y 3,5) y la condición inicial de oxígeno (con y sin oxígeno inicial) en el contenido de dióxido de azufre y compuestos fenólicos seleccionados. Los datos obtenidos de las mediciones de consumo de dióxido de azufre libre y total por el método Ripper y compuestos fenólicos por los métodos Folin-Ciocalteu y precipitación de proteínas, fueron evaluados mediante un análisis de varianza (ANDEVA) y luego se sometieron a un test de separación de medias (test Tukey HSD).Se observó un mayor consumo de dióxido de azufre libre y total en los tratamientos con pH más alto que en los tratamientos con pH bajo. En cuanto a las evaluaciones de compuestos fenólicos, no se encontraron diferencias significativas, probablemente debido al corto tiempo en que fueron evaluadas las muestras.Se concluye, por lo tanto, que la regulación del pH en niveles bajos, permitiría controlar de mejor forma las reacciones de oxidación y la pérdida de dióxido de azufre en el vino./ABSTRACT: White wines have lower concentrations of phenolic compounds, as compared to red wines. Therefore, they exhibit a limited ability to withstand frequent or prolonged exposure to air, without showing signs of oxidation. In the following study, we evaluated the effect of two pH levels (3,0 and 3,5) and two initial conditions of oxygen exposure (with and without initial exposure to oxygen), on the content of sulfur dioxide and selected phenolic compounds.The data obtained from the measurements of free and total sulfur dioxide by the Ripper method, and phenolic compounds by Folin-Ciocalteu and protein precipitation methods was assessed by analysis of variance (ANOVA) and then subjected to a mean separation test of Tukey HSD. A higher consumption of free and total sulfur dioxide was seen for the treatment with higher pH. As far as the phenolic compounds assessment, no significant differences were found, probably due to the short time that the samples were evaluated.Therefore, we conclude that the regulation of pH to low levels enhances their resistance to oxidation and moderate the losses of sulfur dioxide in wine

Tobacco, alcohol, and illicit drug use in adolescents with diabetes mellitus

Background: Substance abuse in adolescents with diabetes mellitus (DM) is associated with the development of acute and chronic complications. Objective: To determine the prevalence of alcohol, tobacco, and illicit drug consumption in adolescents with DM and compare it with the prevalence in a large contemporary control (C) group. Methods: Adolescents with and without DM, who were attending 8th-12th grades, answered a structured written questionnaire, which evaluates the voluntary declaration of tobacco, alcohol, and illicit drug consumption. Subjects with DM were recruited from free diabetes camps or public hospitals (n = 93). The C group was obtained from a nationwide study of prevalence of substance abuse (n =58 489). For illicit drugs (marijuana, cocaine, or cocaine sulfate), results are shown as life prevalence (ever used the substance). For alcohol and tobacco, results are shown as last month prevalence (the substance was used during the last month). Results: Adolescents with DM