Espectroscopia de infravermelho com transformada de Fourier na monitorização da produção de vinho

ReviewThe complexity of the wine matrix makes monitoring of the winemaking process from the grapes to the final product crucial for the wine industry. In this context, analytical methodologies that can combine good accuracy, robustness, high sample throughput, “green character”, and by preference real-time analysis, are on-demand to create high-quality vitivinicultural products. In the last years, Fourier-transform Infrared Spectroscopy (FTIR) combined with chemometric analysis has been evaluated in several studies as an effective analytical tool for the wine sector. Some applications of FTIR spectroscopy have been already accepted by the wine industry, mainly for the prediction of basic oenological parameters, using portable and non-portable instruments, but still many others are waiting to be thoroughly developed. This literature review aims to provide a critical synopsis of the most important studies assessing grape and wine quality and authenticity, and to identify possible gaps for further research, meeting the needs of the modern wine industry and the expectations of most demanding consumers. The FTIR studies were grouped according to the main sampling material used - 1) leaves, stems, and berries; 2) grape must and wine applications - along with a summary of the basic limitations and future perspectives of this analytical techniqueA complexidade da matriz do vinho torna a monitorização da sua produção, desde a maturação da uva até o produto final, fundamental para a indústria do vinho. Neste contexto, metodologias analíticas com boa exactidão, robustez, elevado rendimento de amostras, menos penalizadoras para o meio ambiente, e se possível capazes de fornecer resultados em tempo real, são muito importantes para a obtenção de produtos vitivinícolas de alta qualidade. Nos últimos anos, a Espectroscopia de Infravermelho com Transformada de Fourier (FTIR) combinada com a análise quimiométrica tem sido avaliada em diversos estudos por ser uma ferramenta analítica apropriada para o setor vitivinícola. Algumas aplicações de FTIR já foram adoptadas pela indústria do vinho, principalmente para a predição de parâmetros enológicos básicos, através de instrumentos portáteis e não portáteis, mas há ainda um enorme potencial de desenvolvimento a explorar. A presente revisão da literatura tem como objetivo fornecer uma sinopse crítica dos estudos mais importantes realizados para avaliação da qualidade e autenticidade do vinho e identificar possíveis lacunas para investigação futura, indo ao encontro das necessidades da indústria vinícola moderna e das expectativas dos consumidores mais exigentes. Os estudos sobre FTIR foram agrupados de acordo com o principal material de amostragem - 1) folhas, engaços e bagos; 2) mostos e vinhos - juntamente com informação sobre as limitações básicas e perspectivas futuras desta técnica analíticainfo:eu-repo/semantics/publishedVersio

Sensory quality control of alcoholic beverages using fast chemical sensors

Control de calidad sensorial de bebidas alcohólicas utilizando rápidos sensores químicosEn la presente tesis Doctoral, han sido aplicados dos sensores artificiales para el análisis debebidas alcohólicas: la nariz electrónica basada en la espectrometría de masas (MS) y la lenguaelectrónica basada en la espectroscopía infrarroja con transformada de Fourier (FTIR). Elpropósito fue desarrollar nuevas estrategias para analizar la autenticidad de estos productos,desde un punto de vista sensorial, por medio de técnicas las espectrales antes mencionadas.Adicionalmente, ha sido utilizado un espectrofotómetro UV-visible como ojo electrónico. Eltrabajo presentado pretende ser un avance significativo hacia el desarrollo de un catadorelectrónico mediante la fusión de los tres sensores químicos: nariz electrónica, lenguaelectrónica y ojo electrónico.Sensory quality control of alcoholic beverages using fast chemical sensorsIn the present Doctoral Thesis, two chemical artificial sensors are applied to the analysis ofalcoholic beverages: the Mass Spectrometry (MS)-based electronic-noses and Fouriertransform infrared (FTIR)-based electronic-tongue. The aim was developing new strategies totest the authenticity of these products, from a sensory point of view, by means of the spectraltechniques above mentioned. Additionally, has been used an UV-visible spectrophotometer aselectronic eye. The work presented wants to be a significant advance towards the developmentof an electronic taster through the fusion of three chemical sensors: electronic nose, electronictongue and electronic eye

Chemistry and Technology of Wine Aging with Oak Chips

The use of wood chips is a common winemaking practice that has been permitted in Europe since the early 2000s. The use of oak chips, or other wood alternative products, has not always been favorably viewed by both producers and wine consumers. Beyond possible misuse, however, wood chips are a useful tool for the optimal achievement of numerous oenological objectives, including the extraction of certain volatile odor compounds from oak wood chips as well as compounds that will improve wine quality. This chapter deals with the main oenological uses of oak wood chips, the chemical transformations that underlie this practice and the effect of their utilization on wine quality. A final aspect concerns the main compositional and sensory differences between wines aged in barrel and those aged with alternative products, as well as the discriminative analytical methods used for this purpose

Instrumental and chemometric methodologies to assess sensory quality of Mediterranean food

L'oli d'oliva, el vi o els fruits secs són productes típics de la regió Mediterrània que ofereixen un valor afegit gràcies als seus beneficis per a la salut i excel·lents característiques sensorials. Per aquest motiu és necessari un control de la qualitat i autenticitat d'aquests productes, que són altament susceptibles a fraus i adulteracions. Un aspecte important és l'avaluació de la qualitat sensorial, que descriu paràmetres percebuts pels sentits (gust, visió, olor i tacte) mitjançant panells validats i entrenats d'experts. Aquests panells tendeixen a ser subjectius i requereixen llargs temps d'anàlisi i alts costos. Com a conseqüència hi ha hagut un increment en el desenvolupament de tècniques d'anàlisi capaces de simular les respostes obtingudes amb el panell de tast humà. L'anomenat 'panell electrònic' ofereix respostes objectives mitjançant l'ús de tècniques multivariants que permeten establir correlacions entre els descriptors definits pels humans i els senyals obtingudes instrumentalment. Aquesta tesi pretén oferir tècniques instrumentals alternatives, ràpides i senzilles per determinar la qualitat sensorial d'aliments com l'oli d'oliva, el vi o les ametlles. Els estudis duts a terme inclouen el tractament de les respostes sensorials obtingudes mitjançant metodologies de referència (principalment panells de tast humans), l'optimització dels procediments analítics per treballar amb tècniques instrumentals i el desenvolupament d'eines quimiomètriques adequades per construir els models multivariants. També s'han desenvolupat estratègies de fusió de dades per combinar les diferents dades instrumentals que simulen els sentits humans (olor, gust i visió).El aceite de oliva, el vino o los frutos secos son productos típicos de la región Mediterránea que ofrecen un valor añadido gracias a sus beneficios para la salud y excelentes características sensoriales. Por este motivo es necesario un control de la calidad y autenticidad de estos productos, que son altamente susceptibles a fraudes y adulteraciones. Un aspecto importante es la evaluación de la calidad sensorial, que describe parámetros percibidos por los sentidos (gusto, visión, olor y tacto) mediante paneles validados y entrenados de expertos. Estos paneles tienden a ser subjetivos, requieren largos tiempos de análisis y altos costes. Como consecuencia ha habido un incremento en el desarrollo de técnicas de análisis capaces de simular las respuestas obtenidas con el panel de cata humano. El llamado 'panel electrónico' ofrece respuestas objetivas mediante el uso de técnicas multivariantes que permiten establecer correlaciones entre los descriptores definidos por los humanos y las señales obtenidas instrumentalmente. Esta tesis pretende ofrecer técnicas instrumentales alternativas, rápidas y sencillas para determinar la calidad sensorial de alimentos como el aceite de oliva, el vino o las almendras. Los estudios llevados a cabo incluyen el tratamiento de las respuestas sensoriales obtenidas mediante metodologías de referencia (principalmente paneles de cata humanos), la optimización de los procedimientos analíticos para trabajar con técnicas instrumentales y el desarrollo de herramientas quimiométricas adecuadas para construir los modelos multivariantes. También se han desarrollado estrategias de fusión de datos para combinar los diferentes datos instrumentales que simulan los sentidos humanos (olor, gusto y visión).Olive oil, wine or nuts are typical products of the Mediterranean region that offer added value thanks to its health benefits and excellent sensory characteristics. Therefore, the control the quality and authenticity of these products is necessary, mainly because they are highly susceptible to fraud and adulterations. An important aspect is the evaluation of sensory quality that describe parameters perceived by the senses (taste, sight, smell and touch) using validated and trained panels of experts. These panels tend to be subjective, requiring long-time analysis and high costs. As a result there has been an increase in the development of analytical techniques capable to simulate the responses obtained with the human taste panel. The so-called 'electronic panel' provides objective responses using multivariate techniques, which establish correlations between descriptors defined by humans and signals obtained instrumentally. This thesis aims to offer fast and simple alternative instrumental techniques to determine the sensory quality of foods such as olive oil, wine and almonds. Studies carried out include the treatment of sensory responses obtained by reference methodologies (mainly human taste panels), optimization of analytical procedures to work with instrumental techniques and the development of appropriate chemometric tools to build multivariate models. Data fusion strategies have also been studied by combining different instrumental data that simulate the human senses (smell, taste and sight)

Monitoring wine fermentation using ATR-MIR spectroscopy and chemometric techniques.

El vi és un dels productes amb valor afegit més apreciats al món i és per això que el control de la producció vinícola ha sigut sempre un tema prioritari per a la majoria dels cellers. La implementació d’anàlisis at-line com són les Tècniques Analítiques de Processos (PAT), no només permet un control del vi acabat si no que també dóna la possibilitat de prendre mesures correctives al llarg del procés evitant així obtenir un producte final defectuós. En aquesta tesi doctoral, es va investigar la possibilitat d’implementar diferents estratègies per controlar i detectar desviacions durant la fermentació alcohòlica utilitzant un equip portable i de resposta ràpida: un equip d’ espectroscòpia en l’infraroig mitjà, en el mode de reflectància total atenuada (ATR-MIR) el qual permet obtenir, en pocs segons, una gran quantitat d’informació sobre el procés de fermentació que es va tractar amb diferents tècniques quimiomètriques. Primer, utilitzant les dades espectrals i la regressió de mínims quadrats parcials, es van predir diferents paràmetres químics durant la fermentació alcohòlica. En segon lloc, es van comparar els espectres de fermentacions control amb fermentacions desviades utilitzant l’anàlisi discriminant per mínims quadrats parcialsEl vino es uno de los productos con valor añadido más apreciados del mundo y por ello, el control de la producción vinícola ha sido siempre un tema prioritario para la mayoría de bodegas. La implementación de análisis at-line como son las Técnicas Analíticas de Procesos (PAT), no sólo permite un control del vino acabado si no que también brinda la posibilidad de tomar medidas correctivas a lo largo del proceso evitando así obtener un producto final defectuoso. En esta tesis doctoral, se investigó la posibilidad de implementar diferentes estrategias para controlar y detectar desviaciones durante la fermentación alcohólica utilizando un equipo portátil y de respuesta rápida: un equipo de espectroscopia en el infrarrojo medio, en el modo de reflectancia total atenuada (ATR-MIR) el cual permite obtener, en pocos segundos, una gran cantidad de información sobre el proceso de fermentación que se trató con diferentes técnicas quimiométricas. Primero, usando los datos espectrales y la regresión de mínimos cuadrados parciales, se predijeron distintos parámetros químicos durante la fermentación alcohólica. En segundo lugar, se compararon los espectros de fermentaciones control con fermentaciones desviadas utilizando el análisis discriminante por mínimos cuadrados parcialesWine is one of the most appreciated high added-value products in the world and therefore, controlling wine production has always been a priority for most wineries. Implementing at-line analyses such as Process Analytical Technologies (PAT) guidelines, not only enables a control of the final wine but also gives the possibility to apply correcting measures throughout the process, thus avoiding a defective final product. In this doctoral thesis, we investigated the possibility of implementing different strategies to control and detect deviations during wine alcoholic fermentation using a fast and portable equipment: an Attenuated Total Reflectance Mid-Infrared (ATR-MIR) spectrometer which allows obtaining, in a few seconds, a large amount of information about the fermentation process, which was processed with different chemometric techniques. First, using the spectral data and Partial Least Square Regression, different chemical parameters were predicted during alcoholic fermentation. Secondly, we compared the spectra from both Normal Operation Conditions and deviated fermentations using Partial Least Squares Discriminant Analysis. ANOVA–simultaneous component analysis was applied to study the influence of several factors into the variance of the spectra. Multivariate Curve Resolution Alternating Least Squares was used to model both alcoholic and malolactic fermentations. Finally, a PAT methodolog

Characterisation of grapevine berry samples with infrared spectroscopy methods and multivariate data analyses tools

Thesis (MSc)--Stellenbosch University, 2015.ENGLISH ABSTRACT: Grape quality is linked to the organoleptic properties of grapes, raisins and wine. Many advances have been made in understanding the grape components that are important in the quality of wines and other grape products. A better understanding of the compositional content of grapes entails knowing when and how the various components accumulate in the berry. Therefore, an appreciation of grape berry development is vitally important towards the understanding of how vineyard practices can be used to improve the quality of grapes and eventually, wines. The more established methods for grape berry quality assessment are based on gravimetric methods such as colorimetry, fluorescence and chromatography. These conventional methods are accurate at targeting particular components, but are typically multi-step, destructive, expensive, polluting procedures that might be technically challenging. Very often grape berries are evaluated for quality (only) at harvest. This remains a necessary exercise as it helps viticulturists and oenologists to estimate some targeted metabolite profiles that are known to greatly influence chemical and sensory profiles of wines. However, a more objective measurement of predicting grape berry quality would involve evaluation of the grapes throughout the entire development and maturation cycle right from the early fruit to the ripe fruit. To achieve this objective, the modern grape and wine industry needs rapid, reliable, simpler and cost effective methods to profile berry development. By the turn of the last millennium, developments in infrared instrumentation such as Fourier-transform infrared (FT NIR) and attenuated total reflectance Fourier-transform infrared spectroscopy (ATR FT-IR) in combination with chemometrics resulted in the development of rapid methods for evaluating the internal and external characteristics of fresh fruit, including grapes. The advancement and application of these rapid techniques to fingerprint grape compositional traits would be useful in monitoring grape berry quality. In this project an evaluation of grape berry development was investigated in a South African vineyard setting. To achieve this goal, Sauvignon blanc grape berry samples were collected and characterised at five defined stages of development: green, pre-véraison, véraison, post-véraison and ripe. Metabolically inactivated (frozen in liquid nitrogen and stored at -80oC) and fresh berries were analysed with FT-IR spectroscopy in the near infrared (NIR) and mid-infrared (MIR) ranges to provide spectral data. The spectral data were used to provide qualitative (developmental stage) and quantitative (metabolite concentration of key primary metabolites) information of the berries. High performance liquid chromatography (HPLC) was used to separate and quantify glucose, fructose, tartaric acid, malic acid and succinic acid which provided the reference data needed for quantitative analysis of the spectra. Unsupervised and supervised multivariate analyses were sequentially performed on various data blocks obtained by spectroscopy to construct qualitative and quantitative models that were used to characterise the berries. Successful treatment of data by principal component analysis (PCA) and orthogonal partial least squares discriminant analysis (OPLS-DA) gave statistically significant chemometric models that discriminated the berries according to their stages of development. The loadings from MIR models highlighted the important discriminant variables responsible for the observed developmental stage classification. The best calibration models to predict metabolite concentrations were obtained from MIR spectra for glucose, fructose, tartaric acid and malic acid. The results showed that both NIR and MIR spectra in combination with multivariate analysis could be reliably used to evaluate Sauvignon blanc grape berry quality throughout the fruit’s development cycle. Moreover, the methods used were fast and required minimal sample processing and no metabolite extractions with organic solvent. In addition, the individual major sugar and organic acids were accurately predicted at the five stages under investigation. This study provides further proof that IR technologies are robust and suitable to explore high-throughput and in-field application of grape compound profiling.AFRIKAANSE OPSOMMING: Druifkwaliteit word gekoppel aan die organoleptiese eienskappe van druiwe, rosyntjies en wyn. Baie vooruitgang is reeds gemaak in die begrip van druifkomponente wat belangrik is vir die kwaliteit van wyn en ander druifprodukte. ’n Beter begrip van die samestellende inhoud van druiwe behels om te weet wanneer en hoe die verskeie komponente in die korrel opgaar. ’n Evaluasie van druiwekorrel-ontwikkeling is dus uiters belangrik vir ’n begrip van hoe wingerdpraktyke gebruik kan word om die kwaliteit van druiwe, en uiteindelik van wyne, te verbeter. Die meer gevestigde maniere vir die assessering van druiwekorrelkwaliteit is gebaseer op gravimetriese metodes soos kolorimetrie, fluoressensie en chromatografie. Hierdie konvensionele metodes is akkuraat om spesifieke komponente te teiken, maar behels tipies veelvuldige stappe en is prosesse wat destruktief en duur is, besoedeling veroorsaak, asook moontlik tegnies uitdagend is. In baie gevalle word druiwekorrels (eers) tydens oes vir kwaliteit geëvalueer. Hierdie is steeds ’n noodsaaklike oefening omdat dit wingerdkundiges en wynkundiges help om die metabolietprofiele wat daarvoor bekend is om ’n groot invloed op die chemiese en sensoriese profiele van wyn te hê en dus geteiken word, te skat. ’n Meer objektiewe meting om druiwekorrelkwaliteit te voorspel, sou die evaluering van die druiwe dwarsdeur hulle ontwikkeling- en rypwordingsiklus behels, vanaf die vroeë vrugte tot die ryp vrugte. Om hierdie doelwit te behaal, benodig die moderne druiwe- en wynbedryf vinnige, betroubare, eenvoudiger en kostedoeltreffende metodes om ’n profiel saam te stel van korrelontwikkeling. Aan die einde van die vorige millennium het ontwikkelings in infrarooi instrumentering soos Fourier-transform infrarooi (FT NIR) en attenuated total reflectance Fourier-transform infrarooi spektroskopie (ATR FT-IR) in kombinasie met chemometrika gelei tot die ontwikkeling van vinnige metodes om die interne en eksterne kenmerke van vars vrugte, insluitend druiwe, te meet. Die vooruitgang en toepassing van hierdie vinnige tegnieke om ‘vingerafdrukke’ te bekom van die samestellende kenmerke sal nuttig wees vir die verbetering van druiwekorrelkwaliteit. In hierdie projek is ’n evaluering van druiwekorrelontwikkeling in ’n Suid-Afrikaanse wingerdligging ondersoek. Ten einde hierdie doel te bereik, is Sauvignon blanc druiwekorrelmonsters op vyf gedefinieerde stadiums van ontwikkeling versamel en gekarakteriseer: groen, voor deurslaan, deurslaan, ná deurslaan en ryp. Metabolies geïnaktiveerde (bevrore in vloeibare stikstof en gestoor teen -80oC) en vars korrels is met FT-IR spektroskopie in die naby infrarooi (NIR) and mid-infrarooi (MIR) grense geanaliseer om spektrale data te verskaf. Die spektrale data is gebruik om kwalitatiewe (ontwikkelingstadium) en kwantitatiewe (metabolietkonsentrasie van belangrikste primêre metaboliete) inligting van die korrels te verskaf. High performance liquid chromatography (HPLC) is gebruik om glukose, fruktose, wynsteensuur, appelsuur en suksiensuur te skei en te kwantifiseer, wat die verwysingsdata verskaf het wat vir die kwantitatiewe analise van die spektra benodig word. Ongekontroleerde en gekontroleerde meervariantanalises is opeenvolgend op verskeie datablokke uitgevoer wat met spektroskopie verkry is om kwalitatiewe en kwantitatiewe modelle te verkry wat gebruik is om die korrels te karakteriseer. Suksesvolle behandeling van die data deur hoofkomponent analise (principal component analysis (PCA)) en ortogonale parsiële kleinstekwadraat diskriminant analise (partial least squares discriminant analysis (OPLS-DA)) het statisties betekenisvolle chemometriese modelle verskaf wat die korrels op grond van hulle ontwikkelingstadia onderskei het. Die ladings vanaf die MIR-modelle het die belangrike diskriminantveranderlikes beklemtoon wat vir die klassifikasie van die waargenome ontwikkelingstadium verantwoordelik is. Die beste kalibrasiemodelle om metabolietkonsentrasies te verkry, is vanuit die MIR-spektra vir glukose, fruktose, wynsteensuur en appelsuur bekom. Die resultate toon dat beide die NIR- en MIR-spektra, in kombinasie met meervariantanalise, betroubaar gebruik kan word om Sauvignon blanc druiwekorrelkwaliteit dwarsdeur die vrug se ontwikkelingsiklus te evalueer. Verder is die metodes wat gebruik word, vinnig en het hulle minimale monsterprosessering en geen metabolietekstraksies met organiese oplosmiddel benodig nie. Daarbenewens is die vernaamste suiker en organiese sure individueel akkuraat voorspel op die vyf stadia wat ondersoek is. Hierdie studie verskaf verdere bewys dat IR-tegnologieë robuus en geskik is om hoë-deurset en in-veld toepassings van profielsamestelling van druiweverbindings te ondersoek

Exploring 1H NMR relaxometry for wine traceability and authenticity assessment

Mestrado em Engenharia de Viticultura e Enologia (Double degree) / Instituto Superior de Agronomia. Universidade de Lisboa / Faculdade de Ciências. Universidade do PortoThe development of analytical methodologies for wine authenticity assessment is one of the most challenging issues for the scientific community. In this study, the potential analytical applications of 1H NMR relaxometry, in view to wine authenticity investigation, were explored. For that, proton longitudinal relaxation rate dispersions in the range 0.04-300 MHz were investigated in three white and three red varietal wines from Tapada da Ajuda (Lisbon), obtained from Vitis vinifera L. grape varieties, namely Alvarinho, Arinto, Cabernet Sauvignon, Moscatel Graúdo, Touriga Nacional and Trincadeira, from vintages 2008 and 2017 for a total of twelve bottles. To evaluate rain as an environmental source of variability pluviometric data were considered. Dispersions associable to the presence of paramagnetic ions were observed at low frequencies but the results for wine iron content cannot explain the effect. Correlations between the wine characters and the areas drawn by the most representative relaxometry models show an effect of alcoholic strength by volume, glycerol and total dry matter suggesting wine viscosity to modulate relaxivity. To the best of our knowledge, for the first time wine physical-chemical characteristics and glycerol content have been compared to NMR relaxation rate profiles. To investigate the paramagnetic relaxation and evaluate the relaxation associated to wine hydro-alcoholic matrix, water-ethanol mixtures were tested, and linear regressions were obtained. Comparing the results with bibliographic sources, the paramagnetic enhancement on relaxation profiles was associated to the presence of manganese(II), but no parameters have been fitted from the models. The dispersions highlighted possible cross relaxations in the 1.5-6 MHz frequency range. The presence of nitrogen diluted into the wine could explain this behaviour. To inspect how each physical-chemical parameter impacts on wine relaxation profiles the knowledge of manganese content is crucialN/

Rastreabilidade e autenticidade do vinho: abordagens para a avaliação da origem geográfica, casta e ano de vindima

The aim of this work is to identify and discuss physicochemical wine characteristics, to provide to some extent a link to the vintage, variety, and/or geographical origin. Bibliographic datasets were attempted to provide the main information for topic comprehension, identifying the sources of wine compositional variability and how these can be expressed in terms of the belonging categories. Since all the environmental and technological conditions which vineyard and wine are subjected are rarely known, different sources were inspected. Great importance was given to the study of isotopic composition because of its importance in food frauds detection history. The interaction of the plant genotype with the environmental conditions of the vintage is the main responsible for the wines organic and inorganic fraction variability in terms of both total and relative content. This phenotypical expression, together with human and abiotic variability sources, has been examined since it contains to some extent the information for the discrimination of wines according to their category. Recently, new proton nuclear magnetic resonance (1H NMR) spectroscopy techniques have been under study and, used concurrently to chemometric data management procedures, showed to be an interesting and promising tool for wine characterization according to both vintage and varietyinfo:eu-repo/semantics/publishedVersio