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1.
Appl Microbiol Biotechnol ; 107(20): 6363-6376, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37615721

RESUMO

Sexually transmitted infections (STIs) are a public health problem worldwide, and current diagnostic methods have certain limitations. In recent years, volatile organic compounds (VOCs) have been studied as an alternative diagnostic method. Due to this, this study aimed to detect, in vaginal swabs and urine samples, VOCs emitted by highly prevalent STIs-causing bacteria (Chlamydia trachomatis, Mycoplasma genitalium, and Neisseria gonorrhoeae) to identify potential biomarkers that allow the detection of these STIs. VOCs detected in urine samples showed a better differentiation of patients with STIs due to C. trachomatis from those not infected, with 2,6-dimethyl-4-heptanone as the volatile compound most related to the presence of this bacterium. Among the VOCs most related to M. genitalium in urine, 4-methyltetradecane and 2-methylpentadecane stood out, while 3,4,4-trimethyl-2-cyclohexen-1-one was the VOC most closely related to N. gonorrhoeae infection. Moreover, C12 alcohols were the main VOC family associated with positive samples in all three bacteria, which could indicate the presence of aldehyde reductases in their metabolism. In contrast, alcohols such as 3-methyl-1-heptanol and 1-octanol, as well as dimethyl esters, were more associated with negative samples and may be useful in ruling out an STI caused by one of these three bacteria. In short, the VOCs identified as potential biomarkers in patients with infection by C. trachomatis, M. genitalium, or N. gonorrhoeae could be used in the early diagnosis of these STIs, quickly interrupting the chain of transmission, especially interesting in asymptomatic patients. KEY POINTS: • Sexually transmitted infections are a serious public health problem worldwide. • The study of VOCs in multiple infections is increasing in recent years. • The identification of volatile biomarkers could allow new diagnostic methods.

2.
Appl Microbiol Biotechnol ; 107(9): 3057-3069, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-37000228

RESUMO

Trichomoniasis, a disease caused by Trichomonas vaginalis, is the most common non-viral sexually transmitted infection worldwide. The importance of its diagnosis lies in its ease of transmission and the absence of symptoms in most cases, as occurs in men, which have a significant role as asymptomatic carriers. The most widely used diagnostic methods are the fresh examination of vaginal or urethral secretions and molecular techniques. However, as they have some disadvantages and, sometimes, low sensitivity, new trichomoniasis diagnostic methods are necessary. Volatile organic compounds in clinical samples are effective in the diagnosis of different diseases. This work aimed to study, for the first time, those present in vaginal discharge and urine of patients with Trichomonas vaginalis infection to look for volatile biomarkers. The results showed that volatile compounds such as 2-methyl-1-propanol and cyclohexanone could serve as biomarkers in vaginal discharge samples, as well as 2-octen-1-ol and 3-nonanone in urine. Moreover, 3-hydroxy-2,4,4-trimethylpentyl 2-methylpropanoate found in vaginal discharge, highly correlated to positive patients, is also highly related to urines of patients with trichomoniasis. The biomarkers described in this study might be a promising diagnostic tool. KEY POINTS: • The incidence of Trichomonas vaginalis infection is increasing • Trichomonas vaginalis VOC study in vaginal discharge and urine was performed • The identification of volatile biomarkers could allow a new diagnostic method.


Assuntos
Tricomoníase , Vaginite por Trichomonas , Trichomonas vaginalis , Descarga Vaginal , Masculino , Feminino , Humanos , Vaginite por Trichomonas/diagnóstico , Vaginite por Trichomonas/epidemiologia , Tricomoníase/diagnóstico , Tricomoníase/epidemiologia , Descarga Vaginal/diagnóstico , Descarga Vaginal/epidemiologia , Vagina
3.
Int J Mol Sci ; 24(1)2022 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-36614151

RESUMO

Metabolites produced by an altered gut microbiota might mediate the effects in the brain. Among metabolites, the fecal volatile organic compounds (VOCs) are considered to be potential biomarkers. In this study, we examined both the VOCs and bacterial taxa in the feces from healthy subjects and Alzheimer's disease (AD) patients at early and middle stages. Remarkably, 29 fecal VOCs and 13 bacterial genera were differentiated from the healthy subjects and the AD patients. In general, higher amounts of acids and esters were found in in the feces of the AD patients and terpenes, sulfur compounds and aldehydes in the healthy subjects. At the early stage of AD, the most relevant VOCs with a higher abundance were short-chain fatty acids and their producing bacteria, Faecalibacterium and Lachnoclostridium. Coinciding with the development of dementia in the AD patients, parallel rises of heptanoic acid and Peptococcus were observed. At a more advanced stage of AD, the microbiota and volatiles shifted towards a profile in the feces with increases in hexanoic acid, Ruminococcus and Blautia. The most remarkable VOCs that were associated with the healthy subjects were 4-ethyl-phenol and dodecanol, together with their possible producers Clostridium and Coprococcus. Our results revealed a VOCs and microbiota crosstalk in AD development and their profiles in the feces were specific depending on the stage of AD. Additionally, some of the most significant fecal VOCs identified in our study could be used as potential biomarkers for the initiation and progression of AD.


Assuntos
Doença de Alzheimer , Disfunção Cognitiva , Microbiota , Compostos Orgânicos Voláteis , Humanos , Compostos Orgânicos Voláteis/metabolismo , Doença de Alzheimer/metabolismo , Disfunção Cognitiva/microbiologia , Fezes/microbiologia , Ácidos Graxos Voláteis/metabolismo , Bactérias/metabolismo , Biomarcadores/metabolismo
4.
Thorac Cancer ; 14(36): 3522-3529, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37945317

RESUMO

BACKGROUND: Volatile organic compounds (VOCs) have been studied as possible biomarkers in several diseases, including lung cancer. Early detection of cancer can improve long-term survival rates and the quality of life, so the study of VOCs in exhaled breath and urine has been increasing in recent years. This study aimed to assess the urinary VOCs that are modified after chemotherapy to identify those with the potential to be lung cancer biomarkers that can be monitored during treatment. METHODS: Three urine samples from 10 men with stage IV lung adenocarcinoma were collected, as well as urine samples from 14 men with other types of cancer (control group). All samples were analyzed by headspace-solid phase microextraction gas chromatography coupled with mass spectrometry. RESULTS: A total of 21 urinary VOCs were found with different levels after the administration of chemotherapy, with 2-pentanone being one of those that significantly decreased. Furthermore, 2-pentanone and 3-hydroxy-2,4,4-trimethylpentyl-2-methylpropanoate showed statistically significant differences with the control group. CONCLUSIONS: Chemotherapy administered to patients with advanced lung adenocarcinoma modified the volatile profile of urine. 2-Pentanone, a final product of the increased rate of fatty acid oxidation and protein hypermetabolism, significantly decreased after chemotherapy. Therefore, monitoring its urinary excretion could be very useful since its decrease over time could indicate an adequate response to chemotherapy and arrest of cancer development. Another VOC that could be a potential lung cancer biomarker is 3 hydroxy-2,4,4-trimethylpentyl-2-methylpropanoate, whose origin may be due to inhibition of the propanoic acid metabolic pathway or increased aldehyde dehydrogenase activity.


Assuntos
Adenocarcinoma de Pulmão , Neoplasias Pulmonares , Masculino , Humanos , Cromatografia Gasosa-Espectrometria de Massas/métodos , Neoplasias Pulmonares/diagnóstico , Neoplasias Pulmonares/tratamento farmacológico , Microextração em Fase Sólida/métodos , Quimiometria , Qualidade de Vida , Biomarcadores Tumorais/análise , Adenocarcinoma de Pulmão/tratamento farmacológico
5.
Food Chem ; 399: 133942, 2023 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-36037685

RESUMO

An objective sensory evaluation of extra virgin olive oil (EVOO), involving the chemical characterization of positive attributes, is of interest. These attributes are objectively divided, according to fruitiness, into "green" and "ripe" fruity. This work studied the differentiation in the volatile profile of EVOOs into these two classes, obtained by three analytical methods, including different extraction techniques and detectors and two data processing strategies, and their relation with sensory results. According to the results, each method allowed the characterization of the two classes, providing information on different volatile compounds, which increased in number through PARADISe software (14 more than the conventional processing). Moreover, some volatile compounds showed significant differences between the two classes, 16 highlighted by the variables with importance in projection (VIP) for green fruity (e.g. (Z)-3-hexen-1-ol, methyl ether) and 23 for ripe fruity EVOOs (e.g. (Z)-2-hexen-1-ol), which could be considered as useful markers to complement quality assessment.


Assuntos
Frutas , Compostos Orgânicos Voláteis , Biomarcadores/análise , Frutas/química , Azeite de Oliva/química , Compostos Orgânicos Voláteis/análise
6.
Animals (Basel) ; 13(2)2023 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-36670765

RESUMO

The acorn-fed Iberian pig is known worldwide due to the quality of the resulting products commercialized after a natural and free grazing period of fattening in the dehesa agroforestry ecosystem. The quality regulation of the pig breed reserves "acorn" denomination for only those products obtained from animals exclusively fed grazing acorns and other natural resources; however, sometimes, feed supplementation of the pig's diet is fraudulently employed to reach an earlier slaughtering weight and to increase pig stocking rate, a strategy called postre (meaning "feed supplement"). In this sense, although many studies focused on Iberian pig diet have been published, the field detection of feed use for acorn-fed pig during the last finishing stage foraging in the dehesa, a practice which clashes with the official regulation, has not been explored yet. The present study employs a volatilome analysis (gas chromatography coupled to ion mobility spectrometry) of a non-invasive biological sample (faeces) to discriminate the grazing diet of only natural resources, that acorn-fed Iberian pigs are supposed to have, from those pigs that are also supplemented with feed. The results obtained show the suitability of the methodology used and the usefulness of the information obtained from faeces samples to discriminate and detect the fraudulent use of feed for acorn-fed Iberian pig fattening: a classification success ranging between 86.4% and 100% was obtained for the two chemometric approaches evaluated. These, together with the results of discriminant models, are discussed, in addition to the importance that the methodology optimized implies for the Iberian pig sector and market, which is also introduced. This methodology could be adapted to control organic farming animals or other upstanding livestock production systems which are supposed to be fully dependent on a natural grazing diet.

7.
Food Res Int ; 173(Pt 1): 113320, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37803631

RESUMO

The aim of this work was to study the differentiating volatile profiles of the Spanish protected designation of origin (PDO) fortified wines obtained by headspace solid phase microextraction in conjunction with gas chromatography-mass spectrometry and powerful chemometric tools, to finally identify the marker volatile compounds most related to fortified wine types. Results revealed a satisfactory discrimination, for the first time, of the different types of PDO fortified wines, involving only a reduced number of volatile compounds selected by chemometrics. Thus, 28 volatile compounds were responsible for the differentiation according to ageing type (biological, oxidative, or mixed) resulting useful markers for the identification of each specific type of fortified wine. Among them, some esters were strongly related to biological ageing, aldehydes and acids to oxidative ageing, and lactones to mixed ageing. These volatile molecules involved in their differentiation could explain the unique organoleptic characteristics or attributes of these PDO fortified wines.


Assuntos
Vinho , Vinho/análise , Cromatografia Gasosa-Espectrometria de Massas/métodos , Microextração em Fase Sólida/métodos , Aldeídos/análise , Sensação
8.
Food Chem X ; 19: 100738, 2023 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-37389321

RESUMO

Virgin olive oil (OO) can be classified into three different categories: extra virgin, virgin and lampante. The official method for this classification, based on physicochemical analysis and sensory tasting, is considered useful and effective, although it is a costly and time-consuming process. The aim of this study was to assess the potential of some analytical techniques for classifying and predicting different OO categories to support official methods and to provide olive oil companies with a rapid tool to assess product quality. Thus, mid and near infrared spectroscopies (MIR and NIR) have been compared by using different instruments and with head-space gas chromatography coupled to an ion mobility spectrometer (HS-GC-IMS). High classification success rates in validation models were obtained using IR spectrometers (>70% and > 80% in average for ternary and binary classifications, respectively), although HS-GC-IMS showed greater classification potential (>85% and > 90%).

9.
Microbiol Spectr ; : e0174323, 2023 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-37702485

RESUMO

Bovine tuberculosis is considered a re-emerging disease caused by different species from the Mycobacterium tuberculosis complex (MTC), important not only for the livestock sector but also for public health due to its zoonotic character. Despite the numerous efforts that have been carried out to improve the performance of the current antemortem diagnostic procedures, nowadays, they still pose several drawbacks, such as moderate to low sensitivity, highlighting the necessity to develop alternative and innovative tools to complement control and surveillance frameworks. Volatilome analysis is considered an innovative approach which has been widely employed in animal science, including animal health field and diagnosis, due to the useful and interesting information provided by volatile metabolites. Therefore, this study assesses the potential of gas chromatography coupled to ion mobility spectrometry (GC-IMS) to discriminate cattle naturally infected (field infections) by MTC from non-infected animals. Volatile organic compounds (VOCs) produced from feces were analyzed, employing the subsequent information through chemometrics. After the evaluation of variable importance for the projection of compounds, the final discriminant models achieved a robust performance in cross-validation, as well as high percentages of correct classification (>90%) and optimal data of sensitivity (91.66%) and specificity (99.99%) in external validation. The tentative identification of some VOCs revealed some coincidences with previous studies, although potential new compounds associated with the discrimination of infected and non-infected subjects were also addressed. These results provide strong evidence that a volatilome analysis of feces through GC-IMS coupled to chemometrics could become a valuable methodology to discriminate the infection by MTC in cattle. IMPORTANCE Bovine tuberculosis is endemic in many countries worldwide and poses important concerns for public health because of their zoonotic condition. However, current diagnostic techniques present several hurdles, such as low sensitivity and complexity, among others. In this regard, the development of new approaches to improve the diagnosis and control of this disease is considered crucial. Volatile organic compounds are small molecular mass metabolites which compose volatilome, whose analysis has been widely employed with success in different areas of animal science including animal health. The present study seeks to evaluate the combination of fecal volatilome analysis with chemometrics to detect field infections by bovine tuberculosis (Mycobacterium tuberculosis complex) in cattle. The good robust performance of discriminant models as well as the optimal data of sensitivity and specificity achieved highlight volatilome analysis as an innovative approach with huge potential.

10.
Foods ; 11(19)2022 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-36230084

RESUMO

In recent years, there has been a growing demand for organic extra virgin olive oils (OEVOOs) as quality products with greater added value. The aim of the present work was to determine whether the washing process and time of harvesting (morning or afternoon) plays an important role in the quality of Picual OEVOOs by studying quality parameters (degree of acidity, peroxide value, K232, K270, oxidative stability), and volatile and sensory profiles. Olive fruits were harvested at three maturity stages and within each phase at two times of the day (morning and afternoon). Then, samples were divided into two blocks (washed and unwashed). Volatile profile was obtained by headspace solid-phase microextraction (HS-SPME) coupled to gas chromatography-mass spectrometry (GC-MS). Regarding the physicochemical quality parameters, sensory and volatile profiles, there were no differences between the oils produced under the two treatments applied (washed/non-washed). However, the time of harvesting (morning or afternoon) did influence the volatile and sensory profile, with higher values in the oils obtained from fruits harvested in the morning, being statistically significant for the families of aldehydes, hydrocarbures and lactones. Besides, the olives harvested during the mornings gave rise to oils with higher values in the green and apple fruit attributes.

11.
Animals (Basel) ; 11(9)2021 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-34573637

RESUMO

The potential of two complementary analytical techniques (near infrared spectroscopy, NIRS and gas chromatography-ion mobility spectrometry, GC-IMS) was used to establish the time that Iberian pigs have been fed on acorns and pasture and to verify their genetic purity. For both techniques it was neither necessary to carry out any chemical treatment in advance nor to identify individual compounds. The results showed that both the NIR spectrum and the spectral fingerprint obtained by GC-IMS were affected by the time that the Iberian pig feeds on natural resources. High percentages of correct classification were achieved in the calibration for both techniques: >98% for the days of montanera and >96% for the breed by NIRS and >99% for the days of montanera and >98% for the breed by GC-IMS. The results obtained showed that NIR spectra taken from intact samples is a quick classification method according to the time of montanera and breed.

12.
Anal Chim Acta ; 1126: 52-62, 2020 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-32736724

RESUMO

Capillary electrophoresis with diode array detection (CE-DAD) and multidimensional fluorescence spectroscopy (EEM) second-order data were fused and chemometrically processed for geographical and grape variety classification of wines. Multi-levels data fusion strategies on three-way data were evaluated and compared revealing their advantages/disadvantages in the classification context. Straightforward approaches based on a series of data preprocessing and feature extraction steps were developed for each studied level. Partial least square discriminant analysis (PLS-DA) and its multi-way extension (NPLS-DA) were applied to CE-DAD, EEM and fused data matrices structured as two-way and three-way arrays, respectively. Classification results achieved on each model were evaluated through global indices such as average sensitivity non-error rate and average precision. Different degrees of improvement were observed comparing the fused matrix results with those obtained using a single one, clear benefits have been demonstrated when level of data fusion increases, achieving with the high-level strategy the best classification results.


Assuntos
Vitis , Vinho , Análise Discriminante , Análise dos Mínimos Quadrados , Espectrometria de Fluorescência , Vinho/análise
13.
Food Chem ; 311: 126012, 2020 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-31855771

RESUMO

The aroma profiles of Spanish wine vinegars with Protected Designation of Origin (PDO) were described and compared for the first time by gas chromatography-mass spectrometry-olfactometry (GC-MS-O), odor-active values (OAVs) and quantitative descriptive analysis (QDA). Vinagre de Jerez Reserva (JRE) showed higher percentage of 'grassy-vegetal' impact odorants, while 'spicy' compounds highlighted the Pedro Ximénez category (JPX). Vinagre de Montilla-Moriles Reserva (MRE) had 'buttery-lactic' impact odorants, while 'empyreumatic' and 'sweet' aromas stood out for Pedro Ximénez category (MPX). Vinagre de Condado de Huelva Reserva (CRE) showed a stronger percentage of 'chemical' impact odorants. The key odorants were ethyl propionate, ethyl octanoate, propanoic acid and 4-ethylphenol for JRE, diacetyl and methional/furfural for JPX, acetoin for MRE, ethyl phenylacetate and vanillin for MPX and acetaldehyde diethyl acetal, isobutyl acetate, ethyl isovalerate and guaiacol for CRE. A good relation among the impact odorants and the sensory descriptors was observed.


Assuntos
Cromatografia Gasosa-Espectrometria de Massas/métodos , Odorantes/análise , Compostos Orgânicos Voláteis/análise , Vinho/análise , Ácido Acético/análise , Feminino , Humanos , Masculino , Olfatometria , Análise de Componente Principal , Paladar
14.
Foods ; 9(6)2020 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-32517060

RESUMO

For first time, the new device named thin film solid phase microextraction (TF-SPME) has been used to determine the volatile profile of the Picual and Hojiblanca varieties of extra virgin olive oils. To this end, different traditional sampling methods such as headspace sorptive extraction (HSSE) with polydimethylsiloxane (PDMS) and polyethyleneglycol-modified silicone (EG/Silicone) Twisters® have been compared with the TF-SPME devices coated with different extraction polymeric phases. PARADISe software was used as a non-targeting method to process all data. The best results were obtained by HSSE-PDMS and 2TF-SPME. Moreover, the 2TF-SPME extraction method achieved the most adequate results of linearity for most compounds, according to F-values, while the intermediate precision results were similar for both 2TF-SPME and HSSE-PDMS sampling methods. Different sensitivity was observed between both sampling methods depending on the volatile compound, without being clearly influenced by the polarity of them. Although both sampling methods enabled the main active aroma of olive oil to be determined and for them to be differentiated according to olive variety, the 2TF-SPME method appears to be the most suitable for this goal.

15.
Talanta ; 198: 560-572, 2019 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-30876600

RESUMO

Spain is one of the major producers of high-quality wine vinegars having three protected designations of origin (a.k.a. PDOs): "Vinagre de Jerez", "Vinagre de Condado de Huelva" and "Vinagre de Montilla-Moriles". Their high prices due to their high quality and their high production costs explain the need for developing an adequate quality control technique and the interest in extensive characterization in order to capture the identity of each denomination. In this framework, methodologies based on non-targeted techniques, such as spectroscopies, are becoming popular in food authentication. Thus, for improving vinegar quality assessment, fusion of data blocks obtained from the same samples but different analytical techniques could be a good strategy, since the quantity and quality of sample knowledge could be enhanced providing new insights into the differentiation of vinegars. Therefore, the aim of this manuscript is the development of a multi-platform methodology and a model able to classify the Spanish wine vinegar PDOs. Sixty-five PDO wine vinegars were analyzed by four spectroscopic techniques: Fourier-transform mid-infrared spectroscopy (MIR), near infrared spectroscopy (NIR), multidimensional fluorescence spectroscopy (EEM) and proton nuclear magnetic resonance (1H-NMR). Two different data fusion strategies were evaluated: Mid-level data fusion with different preprocessing, and Common Component and Specific Weights analysis multiblock method. Exploratory and classification analysis on the data from individual techniques were also performed and compared with data fusion models. The data fusion models improved the classification, providing a more efficient differentiation, than the models based on single methods, and supporting the approach to combine these methods to achieve synergies for an optimized PDO differentiation.

16.
Food Res Int ; 123: 298-310, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31284980

RESUMO

The characteristic volatile profile of the Spanish Vinagre de Jerez (VJ), Vinagre de Condado de Huelva (VC) and Vinagre de Montilla-Moriles (VMM) protected designation of origin (PDO) wine vinegars has been studied and compared for the first time by headspace stir bar sorptive extraction-gas chromatography-mass spectrometry (HSSE-GC-MS). The possible markers of each category and PDO were assessed. Acetates were the majority group in all vinegars, while ketones, C13-norisoprenoids and volatile phenols showed significant differences between the three PDOs. Analysis of variance (ANOVA), heatmap and partial least squares-discriminant analysis (PLS-DA) were performed. According to these results, 1-heptanol, methyl nonanoate, 2-methylbutanoic acid, 2,2,6-trimethyl-cyclohexanone, trans-2-decenal, eucalyptol and α-terpineol, were the most significant compounds for differentiating of VC, diacetyl and acetoin, ethyl 3-ethoxypropanoate, 2- and 3-heptanone, 2-methyl-1-hexadecanol, 1-octen-3-ol, p-Cresol and camphene for VMM; and ß-damascenone, 5-hydroxymethylfurfural, 3-heptanol, trans-2-hexen-1-ol and trans-2-hexen-1-yl acetate for VJ. Classification results showed that 100% of PDO samples were correctly classified, reaffirming the utility of the volatile profiles for classifying and authenticating wine vinegar PDOs.


Assuntos
Ácido Acético/análise , Compostos Orgânicos Voláteis/análise , Vinho/análise , Monoterpenos Bicíclicos/análise , Butiratos/análise , Cresóis/análise , Monoterpenos Cicloexânicos/análise , Análise Discriminante , Eucaliptol/análise , Manipulação de Alimentos , Furaldeído/análogos & derivados , Cromatografia Gasosa-Espectrometria de Massas , Heptanol/análise , Cetonas/análise , Norisoprenoides , Sensibilidade e Especificidade
17.
Food Chem ; 287: 115-125, 2019 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-30857680

RESUMO

A practice in wine vinegar production is the addition of grape-must caramel to correct and unify the final colour of different batches. Although current legislation allows it, the effect in vinegars' quality has not been studied yet and it can become a fraud when it is used to simulate the effect of a longer ageing. Therefore, the aim of this work was to assess multidimensional fluorescence as a cost-effective and fast technique for detecting and quantifying grape-must caramel in vinegars. Different amounts of grape-must caramel and multivariate data analysis, as Parallel Factor Analysis (PARAFAC), N-way partial least squares and partial least squares discrimination and regression (NPLS-DA, PLS-DA and NPLS) were studied. Triangle sensory test was also performed. Results demonstrated the ability of this methodology in the detection and quantification of grape-must caramel (low prediction errors, RMSEP ≈ 0.24) and the effects that grape-must caramel has upon a PDO vinegar's final quality.


Assuntos
Ácido Acético/análise , Extratos Vegetais/química , Espectrometria de Fluorescência/métodos , Vitis/química , Vinho/análise
18.
Food Res Int ; 105: 880-896, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29433285

RESUMO

High-quality wine vinegars have been registered in Spain under protected designation of origin (PDO): "Vinagre de Jerez", "Vinagre de Condado de Huelva" and "Vinagre de Montilla-Moriles". The raw material, production and aging processes determine their quality and their aromatic composition. Vinegar volatile profile is usually analyzed by gas chromatography-mass spectrometry (GC-MS), being necessary a previous extraction step. Thus, three different sampling methods (Headspace solid phase microextraction "HS-SPME", Headspace stir bar sorptive extraction "HSSE" and Dynamic headspace extraction "DHS") were studied for the analysis of the volatile composition of Spanish PDO wine vinegars. Multivariate curve resolution (MCR) was used to solve chromatographic problems, improving the results obtained. Principal component analysis (PCA) showed that not all the sampling methods were equally suitable for the characterization and differentiation between PDOs and categories, being HSSE the technique that made able the best vinegar characterization.


Assuntos
Ácido Acético/análise , Análise de Alimentos/métodos , Cromatografia Gasosa-Espectrometria de Massas , Odorantes/análise , Olfato , Microextração em Fase Sólida , Compostos Orgânicos Voláteis/análise , Vinho/análise , Análise Multivariada , Análise de Componente Principal
19.
Food Chem ; 230: 108-116, 2017 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-28407890

RESUMO

This work assesses the potential of multidimensional fluorescence spectroscopy combined with chemometrics for characterization and authentication of Spanish Protected Designation of Origin (PDO) wine vinegars. Seventy-nine vinegars of different categories (aged and sweet) belonging to the Spanish PDOs "Vinagre de Jerez", "Vinagre de Montilla-Moriles" and "Vinagre de Condado de Huelva", were analyzed by excitation-emission fluorescence spectroscopy. A visual assessment of fluorescence landscapes pointed out different trends with vinegar categories. PARAllel FACtor analysis (PARAFAC) extracted the potential fluorophores and their values in the PDO vinegars. This information, coupled with different classification methods (Partial Least Square Discrimination Analysis "PLS-DA" and Support Vectors Machines "SVM"), was able to discriminate the wine vinegar category within each PDO, for which SVM models obtained better results (>92% of classification). In each category, SVM also allows the differentiation between PDOs. The proposed methodology could be used as an analysis method for the authentication of Spanish PDO wine vinegars.


Assuntos
Ácido Acético/análise , Corantes Fluorescentes/análise , Contaminação de Alimentos/análise , Espectrometria de Fluorescência/métodos , Espanha , Vinho
20.
Nutr Hosp ; 33(3): 277, 2016 Jun 30.
Artigo em Espanhol | MEDLINE | ID: mdl-27513504

RESUMO

Introducción: en la actualidad existe un déficit en la evaluación de comedores dirigidos a niños menores de 3 años, a pesar de que se han realizado numerosas intervenciones en los comedores escolares con el fin de conseguir una alimentación segura y adecuada.Objetivo: realizar una evaluación nutricional de los menús ofertados en los centros de educación infantil de Sevilla.Material y métodos: se evaluó la frecuencia, variedad, rotación de alimentos, métodos culinarios e información de los menús de seis centros infantiles de Sevilla. Se valoró el aporte energético y nutricional mediante el programa Dietowin® y el método de pesada.Resultados: las frutas y verduras fueron deficitarias en la mayoría de los menús, y excesivas la carne, patatas, pasta y arroz. Se observó una escasa variedad de recetas por grupo de alimentos y no se daba una información completa del menú. Sin embargo, la variedad de procesos culinarios y la rotación de alimentos fueron adecuadas. Aunque la energía y el aporte de carbohidratos (~55%) se ajustaban a las necesidades, se observó un aporte excesivo de proteínas (~19%) y deficiente de lípidos (< 30%), sobre todo de grasas insaturadas. Respecto a los micronutrientes,solo vitamina C, E y calcio estaban por debajo de lo recomendado.Conclusiones: los centros de educación infantil están haciendo un gran esfuerzo por cumplir las recomendaciones nutricionales, pero todavía deben disminuir el aporte proteico y aumentar las grasas insaturadas de la dieta. Además, deben fomentar la oferta de frutas y verduras, ampliar la variedad de recetas, dar mayor información y disminuir el aporte de alimentos cárnicos.


Assuntos
Fidelidade a Diretrizes/estatística & dados numéricos , Estado Nutricional , Recomendações Nutricionais , Instituições Acadêmicas/estatística & dados numéricos , Pré-Escolar , Feminino , Humanos , Lactente , Masculino , Avaliação Nutricional , Espanha
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