Comportamiento fisiológico y agronómico y calidad de la uva de la variedad Tempranillo, en función de la distancia entre cepas, en el valle del río Duero

EL objetivo general es determinar la respuesta productiva y cualitativa de la especie Vitis vinifera L. a la variación de la distancia entre cepas, manteniendo constante la separación entre filas, en cuatro zonas vitivinícolas de Castilla y León. La variación de la distancia entre cepas pretende la aproximación a su equilibrio vegetativo-productivo para un establecimiento adecuado del viñedo, estudiando los principales parámetros agronómicos y fisiológicos a lo largo del ciclo de la vid. Las cepas fueron conducidas en espaldera en cordón Royat bilateral, con orientación Norte-Sur, y podadas en pulgares a dos yemas. Se ha mantenido la misma carga por metro de espaldera de forma que haya un pámpano por cada 10 cm en los tres tratamientos experimentales estudiados. Dichos tratamientos se han establecido manteniendo un espaciamiento entre filas de 3 m y han consistido en una distancia entre cepas de 1,2 m; de 1,5 m y de 1,8 m.Departamento de Producción Vegetal y Recursos Forestale

Monitoring the phenolic ripening of red grapes using a multisensor system based on metal-oxide nanoparticles

Producción CientíficaThe maturity of grapes is usually monitored by means of the sugar concentration. However, the assessment of other parameters such as the phenolic content is also important because the phenolic maturity has an important impact on the organoleptic characteristics of wines. In this work, voltammetric sensors able to detect phenols in red grapes have been developed. They are based on metal oxide nanoparticles (CeO2, NiO, and TiO2,) whose excellent electrocatalytic properties toward phenols allows obtaining sensors with detection limits in the range of 10−8 M and coefficients of variation lower than 7%. An electronic tongue constructed using a combination of the nanoparticle-based sensors is capable to monitor the phenolic maturity of red grapes from véraison to maturity. Principal Component Analysis (PCA) can be successfully used to discriminate samples according to the ripeness. Regression models performed using Partial Least Squares (PLS-1) have established good correlations between voltammetric data obtained with the electrochemical sensors and the Total Polyphenolic Index, the Brix degree and the Total Acidity, with correlation coefficients close to 1 and low number of latent variables. An advantage of this system is that the electronic tongue can be used for the simultaneous assessment of these three parameters which are the main factors used to monitor the maturity of grapes. Thus the electronic tongue based on metal oxide nanoparticles can be a valuable tool to monitor ripeness. These results demonstrate the exciting possible applications of metal oxide nanoparticles in the field of electronic tongues.Ministerio de Economía, Industria y Competitividad - Fondo Europeo de Desarrollo Regional (project AGL2015-67482- R)Junta de Castilla y Leon - Fondo Europeo de Desarrollo Regional (project VA011U16)Junta de Castilla y León (grant BOCYL-D-24112015-9

The advantages of disposable screen-printed biosensors in a bioelectronic tongue for the analysis of grapes

Producción CientíficaDisposable screen-printed sensors have been modified with enzymes and used to form a bioelectronic tongue dedicated to the discrimination between different grape varieties. The multisensory system combined serigraphied electrodes modified with carbon, platinum, gold, graphene, Prussian blue and nickel oxide nanoparticles (M-SPE) covered with glucose oxidase (M-GOX-SPE) or tyrosinase (M-Tyr-SPE). The M-GOX-SPE and M-Tyr-SPE sensors produced a variety of responses due to the different behavior of the electron mediators of the six screen-printed materials used for the electro-catalysis of the glucose and phenols by means of glucose oxidase and tyrosinase. This variety of responses, together with the capability of the sensors to detect glucose or phenols, allowed the bioelectronic tongue developed here to discriminate between the juices obtained from different varieties of grape. Partial least-squares (PLS-1) multivariate calibration of electrochemical data has been successfully applied to the simultaneous determination of glucose and polyphenols in musts. The discrimination capability shown by this array of cheap and single-use sensors was similar to that found in other complex bioelectronic tongues. The lower price, ease of use and portability of the modified screen-printed electrode system makes the bioelectronic tongue developed here an alternative tool that can be used in situ in the vineyard block.Ministerio de Economía, Industria y Competitividad – FEDER (Grant CICYT AGL2012-33535)Junta de Castilla y León (programa de apoyo a proyectos de investigación - Ref. VA-032U13)University of Valladolid (PIF-UVa

Array of biosensors for discrimination of grapes according to grape variety, vintage and ripeness.

A bioelectronic tongue based on nanostructured biosensors specific for the simultaneous detection of sugars and phenols has been developed. The array combined oxidases and dehydrogenases immobilized on a lipidic layer prepared using the Langmuir-Blodgett technique where Glucose oxidase, d-Fructose dehydrogenase, Tyrosinase or Laccase were imbibed. A phthalocyanine was co-immobilized in the sensing layer and used as electron mediator. The array thus formed has been used to analyze grapes and provides global information about the samples while providing specific information about their phenolic and their sugar content. Using Principal Component Analysis (PCA) the array of voltammetric biosensors has been successfully used to discriminate musts prepared from different varieties of grapes (Tempranillo, Garnacha, Cabernet-Sauvignon, Prieto Picudo and Mencía). Differences could be also detected between grapes of the same variety and cultivar harvested in two successive vintages (2012 and 2013).2020-07-092020-07-0

A different approach for the analysis of grapes: Using the skin as sensing element

In this work, an alternative method to monitor the phenolic maturity of grapes was developed. In this approach, the skins of grapes were used to cover the surface of carbon paste electrodes and the voltammetric signals obtained with the skin-modified sensors were used to obtain information about the phenolic content of the skins. These sensors could easily detect differences in the phenolic composition of different Spanish varieties of grapes (Mencía, Prieto Picudo and Juan García). Moreover, sensors were able to monitor changes in the phenolic content throughout the ripening process from véraison until harvest.2020-07-092020-07-0

Analysis of grapes and wines using a voltammetric bioelectronic tongue. Correlation with the phenolic and sugar content

Producción CientíficaArrays of voltammetric sensors and biosensors based on phthalocyanines have been developed and used to analyze wines and grapes. Nanostructured sensors prepared by the Langmuir-Blodgett (LB), Layer by Layer (LbL) or electro-deposition are superior because the high number of active sites. The LB and the LbL techniques can be used to co-deposit electrocatalytic materials to obtain a synergistic electrocatalytic effect. Moreover, LB and LbL can be used to immobilize enzymes in a biomimetic structure formed by amphiphilic lipids. Such sensors show an enhanced selectivity. The presence of phthalocyanines as electron mediators improves the performance of the sensors. Combining sensors and biosensors in the same array provides the advantages of classical phthalocyanine based-sensors, with the specificity of the enzyme-substrate reaction typical of biosensors. The selectivity of the electronic tongue and its capability of discrimination are clearly improved when biosensors containing glucose oxidase or tyrosinase are included in the array.2022-07-72022-07-0

Electronic tongue formed by sensors and biosensors containing phthalocyanines as electron mediators. Application to the analysis of red grapes

Producción CientíficaAn electronic tongue formed by voltammetric sensors and biosensors containing phthalocyanines has been developed and used to analyze grapes of different varieties. The sensors are prepared using the carbon paste technique and have been chemically modified with different metallophthalocyanines. In turn, biosensors consist of carbon paste electrodes modified with phthalocyanines combined with tyrosinase or glucose oxidase. The response of the individual sensors towards model solutions of glucose and catechol have demonstrated that the voltammetric responses depend on the nature of the phthalocyanine, evidencing the important role of the electron mediator in the performance of the sensors. The capability of the system to discriminate grapes according to their sugar and their polyphenolic content has been evidenced using Principal Component Analysis. It has been demonstrated that the proposed array of sensors combines the advantages of classical phthalocyanine based sensors — that provide global information about the sample —, with the specificity of the enzyme substrate reaction typical of biosensors. For this reason, the selectivity of the multisensor system and its capability of discrimination is clearly improved when biosensors containing glucose oxidase or tyrosinase are included in the array.2022-07-62022-07-0

Monitoring the Phenolic Ripening of Red Grapes Using a Multisensor System Based on Metal-Oxide Nanoparticles

The maturity of grapes is usually monitored by means of the sugar concentration. However, the assessment of other parameters such as the phenolic content is also important because the phenolic maturity has an important impact on the organoleptic characteristics of wines. In this work, voltammetric sensors able to detect phenols in red grapes have been developed. They are based on metal oxide nanoparticles (CeO2, NiO, and TiO2,) whose excellent electrocatalytic properties toward phenols allows obtaining sensors with detection limits in the range of 10−8 M and coefficients of variation lower than 7%. An electronic tongue constructed using a combination of the nanoparticle-based sensors is capable to monitor the phenolic maturity of red grapes from véraison to maturity. Principal Component Analysis (PCA) can be successfully used to discriminate samples according to the ripeness. Regression models performed using Partial Least Squares (PLS-1) have established good correlations between voltammetric data obtained with the electrochemical sensors and the Total Polyphenolic Index, the Brix degree and the Total Acidity, with correlation coefficients close to 1 and low number of latent variables. An advantage of this system is that the electronic tongue can be used for the simultaneous assessment of these three parameters which are the main factors used to monitor the maturity of grapes. Thus the electronic tongue based on metal oxide nanoparticles can be a valuable tool to monitor ripeness. These results demonstrate the exciting possible applications of metal oxide nanoparticles in the field of electronic tongues

Table_1_Monitoring the Phenolic Ripening of Red Grapes Using a Multisensor System Based on Metal-Oxide Nanoparticles.docx

<p>The maturity of grapes is usually monitored by means of the sugar concentration. However, the assessment of other parameters such as the phenolic content is also important because the phenolic maturity has an important impact on the organoleptic characteristics of wines. In this work, voltammetric sensors able to detect phenols in red grapes have been developed. They are based on metal oxide nanoparticles (CeO₂, NiO, and TiO₂,) whose excellent electrocatalytic properties toward phenols allows obtaining sensors with detection limits in the range of 10⁻⁸ M and coefficients of variation lower than 7%. An electronic tongue constructed using a combination of the nanoparticle-based sensors is capable to monitor the phenolic maturity of red grapes from véraison to maturity. Principal Component Analysis (PCA) can be successfully used to discriminate samples according to the ripeness. Regression models performed using Partial Least Squares (PLS-1) have established good correlations between voltammetric data obtained with the electrochemical sensors and the Total Polyphenolic Index, the Brix degree and the Total Acidity, with correlation coefficients close to 1 and low number of latent variables. An advantage of this system is that the electronic tongue can be used for the simultaneous assessment of these three parameters which are the main factors used to monitor the maturity of grapes. Thus the electronic tongue based on metal oxide nanoparticles can be a valuable tool to monitor ripeness. These results demonstrate the exciting possible applications of metal oxide nanoparticles in the field of electronic tongues.</p