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4 Figuras.-- 3 Tablas, Mesh cell is a rapid tool designed to monitor chemical changes that occurs as a consequence of oxidation at moderate conditions. In this study this accessory has been proposed for assessing virgin olive oil (VOO) stability by Fourier transform infrared (FTIR) spectroscopy. Monocultivar VOOs have been stored in mesh cells under different temperatures (at 23, 35, 65 °C) simulating the real conditions during storage and transport ( < 60 °C). In addition to temperature, the samples have been also stored in mesh cells at different light intensities (400, 1000, 7000 lx) to evaluate the resistance of the samples to photooxidation. The oil stability of the samples determined by using this accessory has been compared with the oil stability determined with the common methods used for this purpose (e.g. Rancimat). Despite the moderate conditions applied, mesh cell-FTIR spectra have revealed the formation of hydroperoxides and the subsequent formation of alcohols and aldehydes. Unlike other methods that require high temperature to accelerate the oxidation rate, mesh cell-FTIR has allowed differentiate the oil stability of the samples from a multi-factor perspective that includes several properties (temperature and light) and chemical species (primary and secondary oxidation products). The information obtained with this method can be relevant for optimizing handling (e.g. packaging and storage temperature) of VOO samples during their shelf life., Financial support by Fundación General CSIC (Programa ComFuturo) is acknowledged. This research has been also funded by AGL2015‐69320‐R project (Spanish State Secretariat of Research, Development and Innovation).

10 Páginas.-- 5 Figuras.-- 1 Tabla, Vegetable oils are usually rich in unsaturated fatty acids which are susceptible to oxidation. The oxidation of vegetable oils has been one of the most widely studied fields within lipid chemistry, because it alters their properties and nutritive value, inducing the formation of harmful compounds and off-flavors. Moreover, oxidized vegetable oils display altered physical and chemical properties which are conferred by the newer oxygenated compounds they contain. This is the case of ozonized oils. Ozone is a powerful oxidizing agent that mainly acts on olefinic compounds which generate ozonides and other peroxidic species that can decompose into carbonilic fragments. The action of the oxidant and the later reactions depend on the chemical environment of the reaction as well as the carbonyl termination products resulting from peroxide cleavage. In recent years, sunflower oils with different fatty acid compositions have been developed by breeding and mutagenesis. They displayed higher contents of oleic, stearic or palmitic acids, which mainly alters their triacylglycerol composition. Therefore, four different sunflower oils, common, high oleic, high stearic-high oleic and high palmitic-high oleic, were oxidized with ozone and the progress of the reaction was monitored by measuring the level of oil peroxygenation and the changes in the oils’ fatty acid compositions. The peroxidated species formed during ozonation were studied by FT-IR spectroscopy. The main conclusions of this work were that ozonation caused linear oxidation rates that were similar in all the oils assayed. The addition of water accelerated oxidation, which tended to occur in linoleic polyunsaturated fatty acid The FT-IR pointed to the presence of ozonide-derived peroxides as the major oxygenated species., Caracterización de diferentes aceites de girasol ozonizados I. Cambios químicos durante la ozonización. Los aceites vegetales son generalmente ricos en ácidos grasos insaturados susceptibles de oxidación. La oxidación de aceites vegetales ha sido un campo de estudio intensivo dentro de la química de lípidos ya que este proceso altera sus propiedades y valor nutritivo, induciendo la formación de compuestos perjudiciales y olores y sabores indeseados. Además, los aceites vegetales oxidados muestran propiedades físicas alteradas conferidas por los nuevos compuestos oxigenados que contienen. Este es el caso de los aceites ozonizados. El ozono es un agente oxidante enérgico que actúa sobre los compuestos olefínicos generando ozónidos y otras especies peroxídicas que se descomponen en fragmentos carbonílicos. La acción del oxidante y las reacciones posteriores dependen del entorno químico de la reacción además de los productos carbonílicos de terminación resultante de la rotura de los peróxidos. El aceite de girasol común es rico en oleico y linoleico, susceptibles de ataque oxidativo por parte del ozono. En los últimos años, aceites de girasol con composiciones diferentes de ácidos grasos se han desarrollado por selección y mutagénesis. Estos aceites muestran altos contenidos en oleico, esteárico o palmítico, los cuales alteran de manera importante su composición de triglicéridos. Este trabajo es el primero de una serie de dos en los cuales se estudian los cambios físico-químicos que dichos aceites de girasol experimentan durante la ozonización. Así, se oxidaron con ozono cuatro aceites de girasol diferentes, girasol común, alto oleico, alto esteárico-alto oleico y alto palmítico-alto oleico. Se monitorizaron las cantidades absorbidas de ozono, los niveles de peroxidación y los ácidos grasos que experimentaron oxidación. Las especies formadas en el proceso se estudiaron mediante espectroscopía FT-IR. El modo en que la composición de ácidos grasos del aceite afectó a las cinéticas de oxidación y los productos resultantes se comentaron a la vista de los resultados., This work was funded by the project ICOOP-COOPB20153 from the Consejo Superior de Investigaciones Científicas (CSIC).

7 Figuras.-- 5 Tablas, In order to guarantee food integrity, testing methods should also include the tools needed to verify the geographical origin described on the label. In the particular case of virgin olive oil (VOO), regulatory bodies have yet to establish a standard for geographical identification. This manuscript describes a procedure based on Raman spectroscopy to identify the provenance of these oils based on a classification criterion (European vs non‐European VOOs). The sample collection is considered a relevant step in which multiple factors are taken into account (cultivar distribution, complexity of production in each location, new agricultural practices, and new/old cultivars). A total of 78 virgin olive oils collected around the world allow checking the classification accuracy of the model for identifying sample origin. The PLS‐model built around the Raman spectroscopic data is validated with a blind set of samples, and the results are evaluated in terms of false negative and false positive quality parameters. This study provides an analytical application to detect mislabeling and fraudulent practices related to the geographical provenance of virgin olive oils declared on the labels. Practical Applications: The results of this study provide a robust mathematical model to assess the origin of virgin olive oils (EU vs non‐EU) based on spectroscopic data. Nowadays, the extensive knowledge of olive oil chemical composition has proven that this composition varies according to pedoclimatic conditions, while non‐targeted methods can be proposed in geographical traceability for their ability to analyze the chemical profile of samples. However, it was deemed necessary to conduct a study through a collaborative work initiative. Thus, this study provides a strict evaluation of Raman spectroscopy through a defined strategy for evaluating non‐targeted methods for geographical identification., The authors would like to thank Mr. Quentin Arnould from CRA‐W for the assistance in FT‐Raman analysis. The project has received funding from the European Union's Seventh Framework Programme for research, technological development and demonstration under grant agreement No. 613688 (FoodIntegrity).

The antioxidant activity of anthocyanins in food is well known. Numerous antioxidant assays have been proposed to measure the capacity of anthocyanins to prevent the oxidation process that naturally occurs. Different solvents, temperatures, and pH levels are applied in each assay, and these factors should be taken into account in order to obtain useful and reproducible results. The concentration and the structure of these compounds are directly related to their antioxidant capacity and their environment. However, the effectiveness of the anthocyanin ingestion against diseases is also influenced by its bioavailability. Novel methodologies that simulate the digestion process have been developed in order to facilitate the current knowledge of anthocyanins bioavailability. Studies highlight the potential synergy effect between parent compounds and their derivatives (metabolites, conjugated products, and microbe-generated metabolites). The aim of this review is to provide an overview of advantages and disadvantages of the most common methods to determine the antioxidant activity of anthocyanins, chemical structure, and concentration of these compounds in different edible fruits, vegetables, and plants; their bioavailability after intake; as well as the main therapeutic effect described in the scientific literature.

The present work aimed at examining the combined effect of chlorophyll content and light filtering packaging material on the photo-stability of virgin olive oil (VOO) via mesh cell-FTIR spectroscopy monitoring. Four different VOOs of Koroneiki cultivar differing in total chlorophyll content (∼12–46 mg/kg) were exposed in parallel to direct visible light (6000 lx, 24 °C, 344 h) and FTIR spectra were recorded periodically with or without applying light protection by an industrial filter used for packaging. Findings suggested that the protective role of light filtering material was more evident in the VOO with the lowest total chlorophyll content. Real time monitoring of VOO by mesh cell-FTIR was found to be a useful tool to follow the combined effect of pro-oxidant chlorophylls and the protective light filtering materials on the photo-oxidation process of VOO employing a minute sample amount., Financial support by Fundación General CSIC (Programa ComFuturo) is acknowledged. This work was also supported by Spanish State Secretariat of Research, Development and Innovation (AGL2015‐69320-R project). DT received funding for an Erasmus + Internship.

Developing new approaches to evaluate the stability of edible oils under moderate conditions is highly demanded today to avoid accelerated experiments that are not well correlated with actual shelf life. In particular, low intensity of visible light (photooxidation) needs to be integrated in stability studies, together with mild temperature. Thus, in this work, a strategy based on a >mesh cell>-FTIR to monitor chemical changes in lipid matrices using a combination of light and mild heating was applied. The results were compared with those obtained for the stability of triolein used as a molecular model. The study showed that the moderate light intensity (400 lx) at a low temperature (23 °C) has an early effect on the degradation of lipid matrices that is not observed when they are stored at 35 °C in the absence of light. Thus, the results proved that the exposure to light (400 lx) was more relevant than mild heating (35 °C) in monounsaturated lipid matrices, while polyunsaturated lipid matrices were more sensitive to mild heating.

9 Páginas; 6 Figuras; 1 Tabla, Virgin olive oil quality relates to flavor and unique health benefits. Some of these properties are at the most desirable level when the oil is just extracted, since it is not a product that improves with age. On the contrary, the concentrations of many compounds change during its shelf-life. These changes reveal the aging of the oil but do not necessarily mean decay in sensory properties, so in some cases an aged oil from healthy olives may be better qualified than a fresh one from olives affected by fermentation. The aim of this work is to analyze different methodologies proposed for assessing the quality of virgin olive oil with implications in freshness and aging of the oil, and to highlight the possibilities of rapid spectrofluorimetric techniques for assessing oil freshness by checking the evolution of pigments during storage. The observed change in the selected spectral features and mathematical modelling over time was compared with the accepted model for predicting the amount of pyropheophytin a, which is based on isokinetic studies. The best regression was obtained for 655 nm (adjusted-R2 = 0.91) wavelength, which matches the distinctive band of pigments. The two mathematical models described in this study highlight the usefulness of pigments in the prediction of the shelf-life of extra virgin olive oil., Predicción de la frescura del aceite de oliva virgen extra durante el almacenamiento mediante espectroscopía de fluorescencia. La calidad del aceite de oliva virgen está relacionada con su flavor y sus beneficios únicos para la salud. Algunas de estas propiedades se encuentran en el nivel más deseable cuando el aceite está recién extraído, ya que no es un producto que mejore con el tiempo. Por el contrario, las concentraciones de muchos compuestos cambian a lo largo de la vida útil. Estos cambios revelan el envejecimiento del aceite, pero no implican necesariamente la alteración de las propiedades sensoriales, por lo que en algunos casos un aceite envejecido procedente de aceitunas sanas puede presentar mejor calidad que uno fresco procedente de aceitunas afectadas por procesos de fermentación. El objetivo de este trabajo es estudiar diferentes metodologías propuestas para evaluar la calidad del aceite de oliva virgen con implicaciones en la frescura y el envejecimiento del aceite, destacando las posibilidades de las rápidas técnicas espectrofluorométricas para evaluar la frescura del aceite verificando la evolución de los pigmentos durante el almacenamiento. El cambio observado en las características espectrales seleccionadas y su modelado matemático a lo largo del tiempo se comparó con el modelo aceptado para predecir la cantidad de pirofeofitina a, que se basa en estudios isocinéticos. Los dos modelos matemáticos descritos en este estudio pusieron de manifiesto la utilidad de los pigmentos en la predicción de la vida útil del aceite de oliva virgen extra. La mejor regresión se obtuvo para 655 nm (R2-ajustado = 0,91), longitud de onda que coincide con la banda distintiva de pigmentos., This work was supported by the Spanish State Secretary for Research, Development and Innovation (AGL2015-69320-R).

Food traceability is a growing consumer concern worldwide. Traceability is undertaken primarily at the administrative level, where the use of advanced analytical tools is not available. Nevertheless, the determination of geographical origin is a requirement of the traceability system for the import and export of foodstuffs (EU regulation 178/2002). The topics covered in this book include the history of traceability; legislations and rules; the actual traceability techniques and the potential analytical techniques for food traceability such as molecular methods (e.g. DGGE, SSCP), next generation sequencers (NGS), bio-captors, chromatographic techniques, isotopic analysis that are used for discrimination of organic food, fish, oils. The chromatographic techniques help in the use of volatile compounds analysis. The isotope analysis helps in distinguishing between chicken meat and vegetable oils. Ambient mass spectrometry is used for studying mycotoxines and alkaloids in foodstuffs and their management, food and feed authentication in olive and other plant oils, and wine. Vibrational methods (e.g. NMR and NIRS) are used to trace food by global spectrum. The book reviews the current and future techniques including metabolomic techniques. (Resume d'auteur)

3 Figuras.-- 3 Tablas, The new health claim on >olive oil polyphenols> recently approved by the European Commission has produced a dramatic increase in the interest in these antioxidant compounds. Although this interest has been focused mostly on extra virgin olive oils (EVOOs), virgin olive oils (VOOs) qualified as having non-oxidative sensory defects, mostly caused by fermentation and the action of fungi on olives, may still have a considerable amount of phenols, even though their sensory quality is not flawless. This study is focused on the phenol composition of all the VOO categories: EVOOs with their ample variability in phenolic composition, VOOs with slight defects, lampante virgin olive oils (LVOO), and reference materials of defective VOOs. The average content of phenols in the analyzed EVOOs (410±16mg/kg) is higher than the recommended consumption by the health claim (250mg/kg). VOOs qualified with non-oxidative defects contain high concentrations of phenols (234±27mg/kg), but only samples characterized by the wet-wood sensory defect show concentrations of phenols close to 250mg/kg. Practical application: This study has demonstrated that VOOs with slight sensory defects still have a high concentration of phenols, providing antioxidant properties regarding health benefits and stability. The health claim should be not only applied to the extra virgin olive oil category, but also to some virgin olive oils with sensory defects., This work was supported by the Comisión Interministerial de Ciencia y Tecnología (CICYT‐EU, Spanish and European Government), Spanish State Secretary for Research (Ramón y Cajal Program) and FEDER (CE) in the projects AGL 2011‐30371‐C01‐01 and ‐02. Extra virgin olive oils were supplied by Spanish producers: Vaga de la Estrella SA, Oleoestepa SCA, Aceites 1881 y Aceites del Sur. Commercial virgin olive oils were supplied by FAECA. Standards of defects were supplied by the International Olive Council.

8 Páginas.-- 6 Figuras.-- 1 Tabla, Nowadays there is a strong need for methods capable of differentiating distillers dried grains with solubles (DDGS) according to their geographical and/or botanical origin. In this study, near infrared microscopy (NIRM) has been applied to differentiate corn and wheat DDGS samples and to differentiate corn DDGS from USA, Europe and China. Two multivariate prediction models have been developed for the discriminations. The models have been validated by cross validation and with an external set of samples and have been used to predict the botanical and geographical origin. Furthermore the probability of wrong prediction of the models has been calculated, to assess their performance profile. The prediction showed very good capability of the model to classify samples according to their botanical origin, whereas satisfying results were exclusively obtained when separating samples from China against the pooled set of samples from USA and Europe., The research presented in this paper has received funding from the European Commission's Seventh Framework Programme (FP7/2007-2013) under grant agreement n° 265702 (QSAFFE-project). The authors wish to acknowledge the help of Nanta S.A. Madrid, and Servizo de Seguridade Alimentaria nas Productions Ganadiras (Xunta de Galicia) for providing samples with different botanical origins.