36 research outputs found
Assessment of Virgin Olive Oil Adulteration by a Rapid Luminescent Method
The adulteration of virgin olive oil with hazelnut oil is a common fraud in the food industry,
which makes mandatory the development of accurate methods to guarantee the authenticity and
traceability of virgin olive oil. In this work, we demonstrate the potential of a rapid luminescent
method to characterize edible oils and to detect adulterations among them. A regression model
based on five luminescent frequencies related to minor oil components was designed and validated,
providing excellent performance for the detection of virgin olive oil adulteration
Metabolomics in Alzheimer's disease: The need of complementary analytical platforms for the identification of biomarkers to unravel the underlying pathology
Alzheimer's disease is a complex neurodegenerative disorder characterized by a multi-factorial etiology, not completely understood to date. In this context, the application of metabolomics is emerging in the last years because of its potential to monitor molecular alterations associated with disease pathogenesis and progression, as well as to discover candidate diagnostic biomarkers. However, the huge heterogeneity and dynamism of the human metabolome makes impossible the simultaneous determination of the entire set of metabolites from complex biological samples. Thus, the most common strategy to get a comprehensive overview of the organism's phenotypic expression is the combined use of complementary metabolomic platforms. In this review, we summarize the advantages and limitations of the most important analytical techniques usually employed in metabolomics, including nuclear magnetic resonance, direct infusion mass spectrometry and hyphenated approaches based on the coupling of orthogonal separation mechanisms (i.e. liquid chromatography, gas chromatography, capillary electrophoresis) with mass spectrometry. Moreover, the suitability of metabolomics to unravel the complex pathology underlying to Alzheimer's disease is also presented. (C) 2017 Elsevier B.V. All rights reserved
Potential of Ultraviolet-Visible Spectroscopy for the Differentiation of Spanish Vinegars According to the Geographical Origin and the Prediction of Their Functional Properties
High-quality wine vinegars with unique organoleptic characteristics are produced in
southern Spain under three Protected Designations of Origin (PDO), namely “Jerez”, “Condado
de Huelva” and “Montilla-Moriles”. To guarantee their authenticity and avoid frauds, robust and
low-cost analytical methodologies are needed for the quality control and traceability of vinegars.
In this study, we propose the use of ultraviolet-visible spectroscopy in combination with multivariate
statistical tools to discriminate Spanish wine vinegars according to their geographical origin, as well
as to predict their physicochemical and functional properties. Linear discriminant analysis provided
a clear clustering of vinegar samples according to the PDO with excellent classification performance
(98.6%). Furthermore, partial least squares regression analysis demonstrated that spectral data
can serve as accurate predictors of the total phenolic content and antioxidant activity of vinegars.
Accordingly, UV-Vis spectroscopy stands out as a suitable analytical tool for simple and rapid
authentication and traceability of vinegars
An Overview on the Application of Chemometrics Tools in Food Authenticity and Traceability
The use of advanced chemometrics tools in food authenticity research is crucial for managing the huge amount of data that is generated by applying state-of-the-art analytical methods such as chromatographic, spectroscopic, and non-targeted fingerprinting approaches. Thus, this review article provides description, classification, and comparison of the most important statistical techniques that are commonly employed in food authentication and traceability, including methods for exploratory data analysis, discrimination, and classification, as well as for regression and prediction. This literature revision is not intended to be exhaustive, but rather to provide a general overview to non-expert readers in the use of chemometrics in food science. Overall, the available literature suggests that the selection of the most appropriate statistical technique is dependent on the characteristics of the data matrix, but combining complementary tools is usually needed for properly handling data complexity. In that way, chemometrics has become a powerful ally in facilitating the detection of frauds and ensuring the authenticity and traceability of foods.This research has received funding from the Junta de Andalucía within the framework of the Programa Operativo FEDER 2014-2020 (UHU-202063). R.G.-D. is recipient of a Miguel Servet fellowship (CP21/00120) funded by the Instituto de Salud Carlos III
Hollow-Fiber Liquid-Phase Micro-Extraction Method for the Simultaneous Derivatization, Extraction, and Pre-concentration of Organotin Compounds from Packed Fruit Juices
Organotin compounds are widely employed as pesticides and fungicides in agriculture and as stabilizers for the industrial manufacture of polyvinyl chloride and other polymers. Accordingly, these endocrine disruptors can be found in a variety of foods and beverages. In the present study, we describe the optimization of a hollow-fiber liquid-phase micro-extraction approach for the simultaneous derivatization, extraction, and pre-concentration of butyltin species from commercial fruit juices with the aim of investigating their migration from the packaging. The best extraction efficiencies were achieved by using hexane as the acceptor solvent and a polypropylene fiber length of 2 cm, whereas the agitation speed, extraction temperature, and total extraction time were set at 1100 rpm, 25 ºC, and 10 min, respectively. Using these optimal conditions, the method was satisfactorily validated in terms of linearity (5–1000 µg L−1), limits of detection (0.8–1.8 µg L−1), recovery (80.5–92.1%), intraday precision (10.2–13.1%), inter-day precision (11.0–15.5%), matrix effect (83.2–91.8%), accuracy (85.2–95.2%), specificity, and carryover. The application of this technique to commercial samples obtained from a local market demonstrated that levels of organotin species in packed fruit juices are negligible, in agreement with the limits established by the European Food Safety Authority (0.14 mg of total organotin compounds per kg of food).Open Access funding provided by Universidad de Huelva/ CBUA thanks to the CRUE-CSIC agreement with Springer Natur
Evolution of physicochemical parameters during the thermal-based production of água-mel, a traditional Portuguese honey-related food product
The purpose of this work was to investigate the physicochemical changes occurring during the thermal-based production of água-mel, a traditional Portuguese honey-related food product. The refractive index, color parameters (hue angle, H°; chroma, C*), and the content of total reducing sugars, glucose, fructose, total brown pigments, and 5-hydroxymethylfurfural were monitored along the entire production process, and their evolution was kinetically modelled. Thermal processing caused a gradual decrease in sugars, which was accompanied by the formation of brown pigments and 5-hydroxymethylfurfural, increased concentration of soluble solids as evaluated through refractive index measurements, as well as the appearance of darker colors. In particular, a zero-order kinetic model could explain the changes in H° and reducing sugars, while the evolution of refractive index, brown pigments, 5-hydroxymethylfurfural, C*, fructose, and glucose were best fitted using a first-order kinetics model.This research was funded by FCT—Foundation for Science and Technology (UIDB/04020/2020)
and Proyectos de Cooperación Transfronteriza en la Eurorregión Alentejo-Algarve-Andalucia (“Caracterización
de mieles y productos derivados (água-mel) en el suroeste de la península ibérica. Estudio de su potencial biológico”)info:eu-repo/semantics/publishedVersio
Utilización de heces de nutria como bioindicadores de contaminación por metales pesados en ecosistemas acuáticos continentales
Mechanistic Insights into Alzheimer’s Disease Unveiled through the Investigation of Disturbances in Central Metabolites and Metabolic Pathways
Hydrophilic metabolites are closely involved in multiple primary metabolic pathways and, consequently, play an essential role in the onset and progression of multifactorial human disorders, such as Alzheimer's disease. This review article provides a comprehensive revision of the literature published on the use of mass spectrometry-based metabolomics platforms for approaching the central metabolome in Alzheimer's disease research, including direct mass spectrometry, gas chromatography-mass spectrometry, hydrophilic interaction liquid chromatography-mass spectrometry, and capillary electrophoresis-mass spectrometry. Overall, mounting evidence points to profound disturbances that affect a multitude of central metabolic pathways, such as the energy-related metabolism, the urea cycle, the homeostasis of amino acids, fatty acids and nucleotides, neurotransmission, and others
Effect of time and storage conditions on major volatile compounds of zalema white wine
Changes in quality attributes during bottled storage of white wine were studied. Different storage conditions, temperature, bottle position and exposure to light were studied over 1 year and their effects on major volatile compounds were evaluated. Ethyl lactate and diethyl succinate contents increased after 12 months of storage, whereas isoamyl acetate decreased over this period. The analysis of variance revealed that the temperature had a statistically significant effect on most volatile compounds studied. Multivariate statistical techniques (specifically principal component analysis and linear discriminant analysis) confirmed that temperature is the most important factor, so the samples were distributed into two groups according to storage temperature. A rough differentiation among wines according to the length of storage was also obtained using linear discriminant analysis
Ultrasound-assisted extraction of phenolic compounds from blueberry leaves using natural deep eutectic solvents (NADES) for the valorization of agrifood wastes
The food industry demands novel green solvents for the extraction of bioactive compounds, particularly from residues of the agrifood industry. Herein, an ultrasound-assisted method has been developed for the environmentally friendly extraction of phenolic compounds from blueberry leaves using natural deep eutectic solvents (NADES). After the screening of multiple NADES, the best extraction efficiencies in terms of total phenol content and antioxidant activity were provided by NADES composed of lactate, sodium acetate, and water (3:1:2), and of choline chloride and oxalic acid (1:1). Using a Box–Behnken experimental design, the optimal extraction conditions were achieved by sonicating for 45 min at 65 °C and using solvent:sample ratios of 15 and 75 (v/w) for the NADES based on lactic acid and choline, respectively. Compared with conventional organic solvents, the use of these NADES composed of lactic acid and choline provided superior performance for the recovery of phenolic compounds (1.6-fold and 2.2-fold greater efficacy, respectively) and antioxidant compounds (1.6-fold and 2.8-fold greater efficacy, respectively). The chromatographic characterization of the extracts obtained under these optimized conditions evidenced that the lactic-based NADES enabled the extraction of a wide range of hydroxycinnamic acids and flavonol derivatives, whereas the choline-based NADES was selective towards the extraction of anthocyanins. These results indicate that the proposed method could represent an excellent green alternative for the recovery of phenolic compounds from plant materials and agrifood wastes, with improved extraction efficacy and/or selectivity compared to that provided by traditional organic solvents.9 página