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1.
Sensors (Basel) ; 21(2)2021 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-33445501

RESUMO

This research paper is concentrated on the design of biologically compatible lead-free piezoelectric composites which may eventually replace traditional lead zirconium titanate (PZT) in micromechanical fluidics, the predominantly used ferroelectric material today. Thus, a lead-free barium-calcium zirconate titanate (BCZT) composite was synthesized, its crystalline structure and size, surface morphology, chemical, and piezoelectric properties were analyzed, together with the investigations done in variation of composite thin film thickness and its effect on the element properties. Four elements with different thicknesses of BCZT layers were fabricated and investigated in order to design a functional acoustophoresis micromechanical fluidic element, based on bulk acoustic generation for particle control technologies. Main methods used in this research were as follows: FTIR and XRD for evaluation of chemical and phase composition; SEM-for surface morphology; wettability measurements were used for surface free energy evaluation; a laser triangular sensing system-for evaluation of piezoelectric properties. XRD results allowed calculating the average crystallite size, which was 65.68 Å3 confirming the formation of BCZT nanoparticles. SEM micrographs results showed that BCZT thin films have some porosities on the surface with grain size ranging from 0.2 to 7.2 µm. Measurements of wettability showed that thin film surfaces are partially wetting and hydrophilic, with high degree of wettability and strong solid/liquid interactions for liquids. The critical surface tension was calculated in the range from 20.05 to 27.20 mN/m. Finally, investigations of piezoelectric properties showed significant results of lead-free piezoelectric composite, i.e., under 5 N force impulse thin films generated from 76 mV up to 782 mV voltages. Moreover, an experimental analysis showed that a designed lead-free BCZT element creates bulk acoustic waves and allows manipulating bio particles in this fluidic system.


Assuntos
Acústica/instrumentação , Materiais Biocompatíveis/química , Cerâmica/química , Zircônio/química , Bário/química , Eletroforese/métodos , Desenho de Equipamento , Glicerol/química , Chumbo , Microscopia Eletrônica de Varredura , Azeite de Oliva/química , Espectrometria por Raios X , Espectroscopia de Infravermelho com Transformada de Fourier , Difração de Raios X
2.
Food Chem ; 342: 128357, 2021 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-33508902

RESUMO

Phenolic compounds in virgin olive oil (VOO) contribute to its health properties, organoleptic features and oxidative stability. In this study, a total of 44 olive tree cultivars categorized by the International Olive Council to be among the most internationally widespread varieties were exhaustively and homogenously evaluated by analysis of the VOO phenolic profile during three consecutive crop seasons. Differences among cultivars resulted in up to 15-fold variations in the total phenol concentration. The 'cultivar' factor contributed the most to the variance (66.8% for total phenolic concentration) for almost all the phenols. However, the 'interannual variability' factor and the interaction 'cultivar x interannual variability' exhibited significant influences on specific phenols. According to the phenolic profile of the VOOs, we determined the presence of three groups of cultivars marked by the predominance of secoiridoid derivatives, which supports the phenolic profile as a criterion to be considered in olive breeding programs.


Assuntos
Azeite de Oliva/análise , Fenóis/análise , Cromatografia Líquida de Alta Pressão , Extração Líquido-Líquido , Olea/genética , Olea/crescimento & desenvolvimento , Olea/metabolismo , Fenóis/isolamento & purificação , Melhoramento Vegetal , Análise de Componente Principal , Estações do Ano , Espectrometria de Massas em Tandem
3.
J Environ Manage ; 279: 111810, 2021 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-33341726

RESUMO

Olive Mill Wastewater (OMW) is a polluting residue from the olive oil industry. It is usually stored in open-air unprotected evaporation ponds where their sediments accumulate. This study compares the characteristics of OMW sludges stored for long-time in evaporation ponds and assesses their impact on the underlying soil layer. Physicochemical parameters, toxicity bioassays, and full characterization of the microbial community were analyzed. The extension of the polluting effects was assessed by analysis of toxicity, microbial biomass carbon, and respiration. Geostatistics was used to predict their spatial distribution. Organic matter and polyphenol content besides toxicity levels determine variations between OMW sludges and have a high impact on the microbiota they contain. The microbial community was abundant, diverse, and functionally active. However, the biodegradability of the sludges was hindered by the toxicity levels. Toxicity and biomass carbon were higher on the surface of the ponds than in the soil layer revealing a reduced leach flow and depletion of contaminants. The natural microbiota might be biostimulated by means of applying sustainable and feasible biological treatments in order to favor the OMW sludges bioremediation. These results open up the possibility of solving the environmental concern caused by its storage in similar scenarios, which are common in olive oil-producing countries.


Assuntos
Microbiota , Olea , Biodegradação Ambiental , Resíduos Industriais/análise , Azeite de Oliva , Tanques , Esgotos , Eliminação de Resíduos Líquidos , Águas Residuárias
4.
Food Chem ; 334: 127601, 2021 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-32712491

RESUMO

Quantitative labeling of oil compositions has become a trend to ensure the quality and safety of blended oils in the market. However, methods for rapid and reliable quantitation of blended oils are still not available. In this study, matrix-assisted laser desorption/ionization mass spectrometry (MALDI-MS) was used to profile triacylglycerols in blended oils, and partial least squares regression (PLS-R) was applied to establish quantitative models based on the acquired MALDI-MS spectra. We demonstrated that this new method allowed simultaneous quantitation of multiple compositions, and provided good quantitative results of binary, ternary and quaternary blended oils, enabling good limits of detection (e.g., detectability of 1.5% olive oil in sunflower seed oil). Compared with the conventional GC-FID method, this new method could allow direct analysis of blended oils, analysis of one blended oil sample within minutes, and accurate quantitation of low-abundance oil compositions and blended oils with similar fatty acid contents.


Assuntos
Análise de Alimentos/métodos , Óleos Vegetais/análise , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos , Cromatografia Gasosa/métodos , Ácidos Graxos/análise , Análise de Alimentos/estatística & dados numéricos , Contaminação de Alimentos/análise , Análise dos Mínimos Quadrados , Azeite de Oliva/análise , Óleos Vegetais/química , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/estatística & dados numéricos , Óleo de Girassol/análise , Triglicerídeos/análise
5.
Food Chem ; 336: 127730, 2021 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-32768900

RESUMO

Phenols are responsible for the only health claim of virgin olive oil (VOO) recognized by the European Commission EU 432/2012 and the European Food Safety Authority. In this research, we studied the decrease in the phenolic content of 160 extra VOOs (EVOOs) after 12 months storage in darkness at 20 °C. Phenolic concentration was decreased 42.0 ± 24.3% after this period and this reduction strongly depended on the initial phenolic profile. Hence, EVOOs with predominance in oleacein and oleocanthal experienced a larger decrease in phenolic content than oils enriched in other phenols. Complementarily, hydroxytyrosol and oleocanthalic acid increased significantly in aged EVOOs, which allowed their discrimination from recently produced EVOOs. These changes are explained by degradation of main secoiridoids during storage due to their antioxidant properties. Hydroxytyrosol and oleocanthalic acid can be considered markers of olive oil ageing, although they can also provide information about quality or stability.


Assuntos
Armazenamento de Alimentos/métodos , Azeite de Oliva/química , Fenóis/química , Antioxidantes/química , Área Sob a Curva , Cromatografia Líquida de Alta Pressão , Iridoides/análise , Fenóis/análise , Álcool Feniletílico/análogos & derivados , Álcool Feniletílico/análise , Curva ROC , Espectrometria de Massas em Tandem , Fatores de Tempo
6.
Food Chem ; 337: 127726, 2021 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-32795854

RESUMO

Phenolic compounds contribute to the bioactive properties of olive oil. However, olive oils can only support a health claim concerning the protection against oxidative stress depending on the polyphenolic concentration, requiring effective measures during extraction to preserve/enhance their concentrations. The effect of the malaxation temperature (22, 28 and 34 °C) on the phenolic profile was studied for industrially extracted cv. Cobrançosa oils. Higher malaxation temperatures decreased the contents of the majority of the chromatographically detected compounds (P < 0.05, one-way ANOVA), enabling oils' differentiation. This decreasing trend was observed for hydroxytyrosol and tyrosol bound forms, determinant for the health claim, which were also negatively affected by temperature, despite revealing that all the industrially extracted oils tested supported the health claim. The observed constant free to bound forms ratio showed that the temperature range tested had a minor effect on bound-forms hydrolysis, being both free and bound forms equally affected by temperature.


Assuntos
Saúde , Azeite de Oliva/química , Fenóis/análise , Temperatura , Fenômenos Mecânicos , Fenóis/química
7.
Sci Total Environ ; 752: 141838, 2021 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-32889274

RESUMO

The removal of emerging contaminants (ECs) for water source reclamation, minimizing energy and chemical use, is an environmental concern worldwide. In this study, we used the technologically cleaner pyrolysis and hydrothermal carbonization (HTC) processes to convert olive oil production wastes into chars in order to simultaneously remove triclosan (TCS), ibuprofen (IBP) and diclofenac (DCF) from water. The chars prepared from olive stone (S), olive tree pruning (P) and pitted and reprocessed wet olive mill waste (H), as well as commercial biochars and a commercial active carbon (CAC), were characterized using different techniques and assayed as adsorbents. Pyrolysis temperatures had only a slight effect on the adsorption capacity of chars. The pseudo second-order reaction kinetic and the Freundlich equation provided the best fit for experimental data. The pH values of char suspensions were negatively correlated with their maximum adsorption capacities. The hydrochars synthetized at the lowest temperatures (≤ 240 °C), which had an acidic pH and were rich in oxygenated functional groups, recorded the highest adsorption rates (64% for DCF, 43% for IBP) and especially for TCS, with a rate of 98%, despite of a low surface area of 7.5 m2/ g. This study demonstrates for the first time that unmodified hydrochars from pitted and reprocessed wet olive mill waste are inexpensive, sustainable and environmentally friendly adsorbents which can be used to remove ECs and other similar compounds in water treatments.


Assuntos
Poluentes Químicos da Água , Purificação da Água , Adsorção , Carvão Vegetal , Azeite de Oliva , Poluentes Químicos da Água/análise
8.
Sci Total Environ ; 752: 141713, 2021 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-32892041

RESUMO

Olive mill wastewater (OMW) is nowadays considered as a serious source pollution. At the same time, it contains high amounts of nutrients, especially potassium and phosphorus that could be recovered for agricultural purposes. The aim of the current experimental research work is to investigate the agronomic potential use of OMW based biochar produced from the slow pyrolysis at 500 °C of raw cypress sawdust (CS) impregnated with OMW (ICS-OMW-B). In order to understand the contribution of OMW, two additional biochars were produced from raw cypress sawdust (RCS-B) and cypress sawdust pretreated with potassium chloride (ICS-K-B). Results indicated that RCS impregnation by OMW significantly improved the produced biochar's chemical properties, especially its nutrients contents. Furthermore, in comparison with the other biochars, ICS-OMW-B application as an organic fertilizer showed promising results in terms of produced fresh and dry masses, as well as potassium bioavailability as assessed in test experiments with ryegrass. For instance, the dry matter masses of the rye-grass treated with ICS-OMW-B were about 23, 34 and 50 wt% higher than the ones measured for the tests using RCS-B, ICS-K-B and synthetic K-fertilizer as amendments, respectively. Besides, this biochar has a potential effect on the suppression of various pathogens existing in the tested agricultural soil. All these results demonstrated that the biochar generated from the slow pyrolysis of impregnated sawdust with OMW could be considered as attractive and promising organic fertilizer for acidic agricultural soils.


Assuntos
Cupressus , Olea , Carvão Vegetal , Resíduos Industriais/análise , Azeite de Oliva , Solo , Águas Residuárias
9.
Food Chem ; 340: 128095, 2021 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-33007696

RESUMO

This article evaluates the use of emulsion gels (EGs) containing two different solid polyphenol extracts [from grape seed (R-EPG) or grape seed and olive (R-EPGO)] as animal fat replacers in the development of frankfurters. The incorporation of EGs improved their lipid content, particularly R-EPG and R-EPGO also contained high levels of phenolic compounds (hydroxytyrosol and flavanols). These frankfurters were judged acceptable by the panellists and showed good thermal and storage stability. Colour parameters, pH and textural properties were affected (p < 0.05) by the formulation, being significant the influence of polyphenols extracts. Spectroscopic results showed greater (p < 0.05) inter- and intramolecular lipid disorder in the frankfurters with EGs, irrespective of the presence of polyphenol extracts. Comparing the reduced-fat samples, R-EPG and R-EPGO showed the lowest (p < 0.05) total viable counts. Significant changes in pH and texture parameters were observed during chilled storage while lipid structure was not affected.


Assuntos
Gorduras na Dieta , Emulsões/química , Produtos da Carne , Polifenóis/química , Animais , Cor , Géis/química , Extrato de Sementes de Uva , Humanos , Concentração de Íons de Hidrogênio , Lipídeos/análise , Produtos da Carne/análise , Produtos da Carne/microbiologia , Olea/química , Azeite de Oliva/química , Espectroscopia de Infravermelho com Transformada de Fourier , Paladar
10.
J Oleo Sci ; 69(11): 1373-1380, 2020 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-33055436

RESUMO

According to CODEX, moisture and volatile matter are olive oil quality parameters and the development of a rapid screening method for the determination of moisture is of interest. We recently demonstrated for the first time that the weak near-infrared (NIR) band near 5260 cm-1 is primarily attributed to a water O-H combination band. To determine the intensity of this band, we measured the peak-to-peak (p-p) height of its first derivative and generated exponential calibration curves for p-p height versus gravimetrically determined concentrations of spiked water in olive oils that had been purged of their initial moisture contents. To further optimize this univariate calibration method, calibration curves were generated in the present study based on plotting the moisture band first derivative p-p heights for neat olive oils (that were neither purged nor spiked) versus the moisture concentrations obtained by the Karl-Fischer (KF) primary reference method. To enhance the speed of FT-NIR data collection, measurements were carried in the transmission mode using disposable glass tubes. We also developed and compared a multivariate partial least squares approach to the univariate one. All the spectra were collected in two separate laboratories using two FT-NIR spectrometers of the same brand and model and no significant difference (p > 0.05) was found between the two laboratory determinations and the KF reference values at a 95% confidence interval. High accuracies were found with the two FT-NIR instruments used, as indicated by the low root mean squared error (RMSE, %) for predicted values obtained with the univariate procedure (RMSE = 0.008% and 0.010%) and the multivariate one, which yielded an even lower value (RMSE= 0.007% for both instruments). These results suggest that, once validated, the FT-NIR approach could potentially be a rapid substitute for the KF method.


Assuntos
Análise de Alimentos/métodos , Qualidade dos Alimentos , Azeite de Oliva/química , Espectroscopia de Infravermelho com Transformada de Fourier/métodos , Espectroscopia de Luz Próxima ao Infravermelho/métodos , Água/análise , Calibragem , Sensibilidade e Especificidade
11.
Pediatrics ; 146(4)2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32978295

RESUMO

Although infants with meconium ileus usually present with apparent symptoms shortly after birth, the diagnosis of meconium ileus and cystic fibrosis (CF) may be delayed, awaiting newborn screening (NBS) results. We present the case of an 11-day-old term girl with delayed passage of meconium at 48 hours who had 2 subsequent small meconium stools over the following week. There was a normal feeding history and no signs of abdominal distension or distress. She then presented with an acute abdomen, decompensated shock, bowel perforation, and peritonitis, requiring multiple intestinal surgeries. Her NBS for CF was positive, and CF was ultimately confirmed with mutation analysis. Her course was complicated by prolonged parenteral feedings and mechanical ventilation via tracheostomy. The infant was managed with soy oil, medium chain triglycerides, olive oil, fish oil lipids and experienced only transaminitis without cholestasis and no chronic liver sequelae, with subsequent normalization of her transaminases without treatment. Because her only symptom was decreased stool output and NBS results were unavailable, the CF diagnosis was delayed until she presented in extremis. Delayed meconium passage and decreased stool output during the first week of life should lead to suspicion and additional evaluation for CF while awaiting NBS results. Careful monitoring is indicated to prevent serious, life-threatening complications. The use of soy oil, medium chain triglycerides, olive oil, fish oil lipids for infants requiring prolonged parenteral nutrition may also be considered proactively to prevent cholestasis, particularly for high risk groups.


Assuntos
Fibrose Cística/diagnóstico , Íleo Meconial/diagnóstico , Colestase/prevenção & controle , Diagnóstico Tardio , Feminino , Óleos de Peixe/uso terapêutico , Humanos , Recém-Nascido , Lipídeos/administração & dosagem , Íleo Meconial/terapia , Azeite de Oliva/uso terapêutico , Nutrição Parenteral , Óleo de Soja/uso terapêutico , Triglicerídeos/administração & dosagem
12.
PLoS One ; 15(9): e0237946, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32881925

RESUMO

Dietary fat is discussed to be critical in the development of non-alcoholic fatty liver disease. Here, we assess the effect of exchanging dietary fat source from butterfat to extra virgin olive oil on the progression of an already existing diet-induced non-alcoholic fatty liver disease in mice. Female C57BL/6J mice were fed a liquid butterfat-, fructose- and cholesterol-rich diet (BFC, 25E% from butterfat) or control diet (C, 12%E from soybean oil) for 13 weeks. In week 9, fat sources of some BFC- and C-fed mice were switched either to 25E% or 12E% olive oil (OFC and CO). Glucose and insulin tolerance tests were performed, and markers of liver damage and glucose metabolism were assessed. After 6 weeks of feeding, BFC-fed mice had developed marked signs of insulin resistance, which progressed to week 12 being not affected by the exchange of fat sources. Liver damage was similar between BFC- and OFC-fed mice. Markers of lipid metabolism and lipid peroxidation in liver and of insulin signaling in liver and muscle were also similarly altered in BFC- and OFC-fed mice. Taken together, our data suggest that exchanging butterfat with extra virgin olive oil has no effect on the progression of non-alcoholic fatty liver disease and glucose tolerance in mice.


Assuntos
Resistência à Insulina , Fígado/efeitos dos fármacos , Hepatopatia Gordurosa não Alcoólica/patologia , Azeite de Oliva/farmacologia , Animais , Peso Corporal/efeitos dos fármacos , Dieta Hiperlipídica , Progressão da Doença , Feminino , Glucose/metabolismo , Teste de Tolerância a Glucose , Insulina/metabolismo , Metabolismo dos Lipídeos/efeitos dos fármacos , Peroxidação de Lipídeos/efeitos dos fármacos , Fígado/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Hepatopatia Gordurosa não Alcoólica/veterinária , Receptor de Insulina/genética , Receptor de Insulina/metabolismo , Transdução de Sinais/efeitos dos fármacos
13.
PLoS Med ; 17(9): e1003282, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32903262

RESUMO

BACKGROUND: Endothelial dysfunction is a crucial step in atherosclerosis development, and its severity is determinant for the risk of cardiovascular recurrence. Diet may be an effective strategy to protect the endothelium, although there is no consensus about the best dietary model. The CORonary Diet Intervention with Olive oil and cardiovascular PREVention (CORDIOPREV) study is an ongoing prospective, randomized, single-blind, controlled trial in 1,002 coronary heart disease (CHD) patients, whose primary objective is to compare the effect of 2 healthy dietary patterns (low-fat versus Mediterranean diet) on the incidence of cardiovascular events. Here, we report the results of one secondary outcome of the CORDIOPREV study: to evaluate the effect of these diets on endothelial function, assessed by flow-mediated dilation (FMD) of the brachial artery. METHODS AND FINDINGS: From the total participants taking part in the CORDIOPREV study, 805 completed endothelial function study at baseline and were randomized to follow a Mediterranean diet (35% fat, 22% monounsaturated fatty acids [MUFAs], and <50% carbohydrates) or a low-fat diet (28% fat, 12% MUFAs, and >55% carbohydrates), with endothelial function measurement repeated after 1 year. As secondary objectives and to explore different underlying mechanisms in the modulation of endothelial function, we quantified endothelial microparticles (EMPs) and endothelial progenitor cells (EPCs) and evaluated, in 24 preselected patients, in vitro cellular processes related to endothelial damage (reactive oxygen species, apoptosis, and senescence) and endothelial repair (cell proliferation and angiogenesis), as well as other modulators (micro-RNAs [miRNAs] and proteins). Patients who followed the Mediterranean diet had higher FMD (3.83%; 95% confidence interval [CI]: 2.91-4.23) compared with those in the low-fat diet (1.16%; 95% CI: 0.80 to 1.98) with a difference between diets of 2.63% (95% CI: 1.89-3.40, p = 0.011), even in those patients with severe endothelial dysfunction. We observed higher EPC levels (group difference: 1.64%; 95% CI: 0.79-2.13, p = 0.028) and lower EMPs (group difference: -755 EMPs/µl; 95% CI: -1,010 to -567, p = 0.015) after the Mediterranean diet compared with the low-fat diet in all patients. We also observed lower intracellular reactive oxygen species (ROS) production (group difference: 11.1; 95% CI: 2.5 to 19.6, p = 0.010), cellular apoptosis (group difference: -20.2; 95% CI: -26.7 to -5.11, p = 0.013) and senescence (18.0; 95% CI: 3.57 to 25.1, p = 0.031), and higher cellular proliferation (group difference: 11.3; 95% CI: 4.51 to 13.5, p = 0.011) and angiogenesis (total master segments length, group difference: 549; 95% CI: 110 to 670, p = 0.022) after the Mediterranean diet than the low-fat diet. Each dietary intervention was associated with distinct changes in the epigenetic and proteomic factors that modulate biological process associated with endothelial dysfunction. The evaluation of endothelial function is a substudy of the CORDIOPREV study. As in any substudy, these results should be treated with caution, such as the potential for false positives because of the exploratory nature of the analyses. CONCLUSIONS: Our results suggest that the Mediterranean diet better modulates endothelial function compared with a low-fat diet and is associated with a better balance of vascular homeostasis in CHD patients, even in those with severe endothelial dysfunction. CLINICAL TRIAL REGISTRATION: URL, http://www.cordioprev.es/index.php/en. clinicaltrials.gov number NCT00924937.


Assuntos
Doença das Coronárias/dietoterapia , Endotélio/metabolismo , Idoso , Doenças Cardiovasculares/prevenção & controle , Dieta com Restrição de Gorduras , Dieta Mediterrânea , Gorduras na Dieta , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Azeite de Oliva , Estudos Prospectivos , Proteômica , Método Simples-Cego
14.
J Oleo Sci ; 69(9): 973-984, 2020 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-32788511

RESUMO

China has taken olive cultivation as a significant part of its agricultural development. Longnan city of Gansu province was marked into the world olive distribution map by International Olive Oil Council in 1998. However, so far, little research has been done on the growth and development stages of Chinese olives. The objective of this study was to investigate the dynamics changes of several quality characteristics of olive oil at different sampling times. Olive fruit of 'Chenggu-32' grown in Longnan were harvested at twenty-four time periods and used for determination of phenotypic traits and oil quality characteristics: total polyphenols and flavonoids contents, as well as fatty acid composition by using Gas Chromatography-Mass Spectrometer (GC-MS) and analysed by using Principal Components Analysis (PCA). Towards maturation, fruit moisture content decreased while oil content increased. Levels of both total flavonoids and total polyphenols contents slightly decreased first then increased. The ratio of unsaturated to saturated fatty acids was close to three. The ratio of monounsaturated fatty acids (MUFA)/ polyunsaturated fatty acids (PUFA) was from 2.28 to 4.05. The oleic acid (C18:1)/linoleic acid (C18:2) ratio was varied between 5.23 and 10.67 according to different sampling dates. The olive oil had lower oleic acid (C18:1) levels, higher linoleic acid (C18:2), linolenic acid (C18:3), and palmitic acid (C16:0) levels compared to Codex values (2017) in some periods, which is the characteristics fatty acid composition of 'Chenggu-32' variety in Longnan, China.


Assuntos
Olea/química , Olea/genética , Azeite de Oliva/análise , Fenótipo , China , Ácidos Graxos Monoinsaturados/análise , Ácidos Graxos Insaturados/análise , Flavonoides/análise , Análise de Alimentos , Qualidade dos Alimentos , Cromatografia Gasosa-Espectrometria de Massas , Ácido Linoleico/análise , Olea/classificação , Ácido Oleico/análise , Ácido Palmítico/análise , Polifenóis/análise
15.
J Chromatogr A ; 1629: 461474, 2020 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-32823012

RESUMO

A 'heart-cut' multidimensional gas chromatography‒mass spectrometry (H/C MDGC‒MS) method for separation and identification of triacylglycerols (TAGs) in extra virgin olive oil was developed. A GC configuration, comprising a non-polar first dimension (1D) column (15 m length) and a mid-polarity second dimension (2D) column (9 m length), was employed. Standard TAGs were used to test and demonstrate the H/C MDGC method, for identification of TAG components and to validate the method. Various chromatographic conditions such as column flow and temperature program were evaluated. The 1D separation resulted in overlap of some standard TAG peaks. These overlapped 1D regions of the standard TAGs were H/C to 2D for further separation and resulted in clearly distinguished individual TAG component peaks. The 1D separation of olive oil TAGs displayed three major peaks and four minor peaks. The application of the H/C MDGC method to olive oil TAGs resulted in the separation of each sampled 1D region into two or more TAG peaks. TAG components in olive oil resolved on the 2D column were identified based on characteristic mass fragment ions such as [M-RCO2]+, [RCO+128]+, [RCO+74]+ and RCO+ and comparison of their mass spectra with that of the standard TAGs. Sixteen olive oil TAGs were identified by MS after 2D separation. The repeatability of the H/C method was evaluated in terms of retention time shift and area response in the 2D and found to be <0.02% and <8% RSD respectively.


Assuntos
Cromatografia Gasosa-Espectrometria de Massas/métodos , Azeite de Oliva/química , Triglicerídeos/isolamento & purificação , Limite de Detecção , Padrões de Referência , Reprodutibilidade dos Testes , Processamento de Sinais Assistido por Computador , Temperatura , Triglicerídeos/química
16.
J Chromatogr A ; 1627: 461397, 2020 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-32823102

RESUMO

A new and sensitive analytical method for the simultaneous determination of secondary lipid peroxidation aldehydes has been successfully developed and validated. Malondialdehyde, acrolein, formaldehyde, acetaldehyde, propanal, and pentanal were extracted and derivatized using 2,4-dinitrophenylhydrazine (DNPH) by gas-diffusion microextraction (GDME) combined with dispersive liquid-liquid microextraction (DLLME) for gas chromatography-mass spectrometry (GC-MS) analysis. The experimental conditions have been optimized by experimental designs. The analytical method validation, in accordance to the Food and Drug Administration (FDA) guidance, provided good results in terms of linearity with r2≥0.9974, in the range from 0.15 or 0.3 µg·g-1 to 3 µg·g-1. Limits of detection and limits of quantification were 0.05 or 0.10 and 0.15 or 0.3 µg·g-1, respectively. Precision was tested as a relative standard deviation (RSD≤ 9.5%) and recoveries were between 95% and 110%. The method was applied in the characterization of aldehydes in forty-eight edible oil samples; with the highest concentration found in pomace olive oil for malondialdehyde at 6.64 µg·g-1.


Assuntos
Acetaldeído/análise , Acroleína/análise , Cromatografia Gasosa-Espectrometria de Massas/métodos , Microextração em Fase Líquida/métodos , Malondialdeído/análise , Óleos Vegetais/análise , Acetaldeído/isolamento & purificação , Acroleína/isolamento & purificação , Aldeídos/análise , Aldeídos/isolamento & purificação , Limite de Detecção , Peroxidação de Lipídeos , Malondialdeído/isolamento & purificação , Azeite de Oliva/análise , Reprodutibilidade dos Testes
17.
J Oleo Sci ; 69(8): 809-814, 2020 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-32641604

RESUMO

In this work, the evolution of virgin olive oil from 4 olive varieties when stored at 5°C, 10°C and 20°C for a period of up to 3 years was studied. Free acidity increased progressively for the 4 varieties, staying below the limit for extra virgin olive oil, even at the highest temperature. The peroxide value also increased, reaching its maximum after about 28 months of storage, when some samples stored at 20°C exceeded the limit for extra virgin olive oil. The maximum values for K270 and K232 were reached at the end of the storage period, also exceeding the limit for extra virgin olive oil in the case of some varieties stored at 20°C. Oxidative stability decreased by 38%-50% depending on the storage temperature and the variety. Most of the color indexes increased in value because of the degradation of the oil pigments.


Assuntos
Armazenamento de Alimentos/métodos , Azeite de Oliva/química , Temperatura , Cor , Azeite de Oliva/análise , Oxirredução , Peróxidos/análise , Pigmentos Biológicos/química , Fatores de Tempo
18.
Food Chem ; 332: 127405, 2020 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-32603919

RESUMO

The two-phase technology for olive oil extraction generates large amounts of patè olive cake (POC), a by-product that is rich in bioactive health-promoting compounds. Here, response surface methodology (RSM) was used to maximize supercritical-CO2 oil extraction from POC, while minimizing operative temperature, pressure and time. Under the optimal parameters (40.2 °C, 43.8 MPa and time 30 min), the oil yield was 14.5 g·100 g-1 dw (~65% of the total oil content of the freeze-dried POC matrix), as predicted by RSM. Compared with freeze-dried POC, the oil contained more phytosterols (13-fold), tocopherols (6-fold) and squalene (8-fold) and was a good source of pentacyclic triterpenes. When the biological effects of POC oil intake (20-40 µL·die-1) were evaluated in the livers of BALB/c mice, no significant influence on redox homeostasis was observed. Notably, a decline in liver triglycerides alongside increased activities of NAD(P)H:Quinone Oxidoreductase 1, Carnitine Palmitoyl-CoA Transferase and mitochondrial respiratory complexes suggested a potential beneficial effect on liver fatty acid oxidation.


Assuntos
Cromatografia com Fluido Supercrítico/métodos , Azeite de Oliva/química , Animais , Dióxido de Carbono/química , Peroxidação de Lipídeos , Fígado/efeitos dos fármacos , Fígado/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Olea/metabolismo , Azeite de Oliva/isolamento & purificação , Azeite de Oliva/farmacologia , Fitosteróis/química , Fitosteróis/isolamento & purificação , Propriedades de Superfície , Temperatura , Tocoferóis/química , Tocoferóis/isolamento & purificação , Triglicerídeos/metabolismo
19.
Food Chem ; 333: 127454, 2020 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-32679414

RESUMO

This study presents a method to determine adulteration of olive oil (obtained from Olea europea, i.e. olives) with rapeseed oil (obtained from Brassica napus) or with corn oil (also named maize oil, obtained from Zea mays, i.e. maize) using Raman spectroscopy and a mathematical method based on exponential equation fit. The samples were prepared by mixing olive oil with volume fractions (0-100%) of rapeseed or corn oil. The oils were differentiated spectroscopically using intensity ratio for specific Raman peaks; Raman spectroscopy is able to detect changes within a liquid molecular environment without the need for sample treatment. It was possible to determine rapeseed or corn oil volume fractions added into the olive oil using the method proposed. Thus, the potential of Raman spectroscopy as a technique for determining adulteration of olive oil was corroborated clearly, opening the potential to investigate adulteration of other liquid foods, without any need for sample preparation.


Assuntos
Óleo de Milho/química , Contaminação de Alimentos/análise , Azeite de Oliva/análise , Óleo de Brassica napus/química , Análise Espectral Raman/métodos , Análise de Alimentos/métodos , Azeite de Oliva/química
20.
J Oleo Sci ; 69(7): 677-684, 2020 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-32522947

RESUMO

A simple screening method for discrimination between commercial extra virgin olive oils and their blends with other vegetable oils was developed. Squalene, which was contained relatively high amounts in virgin olive oil, was determined by HPLC after a simple pretreatment that was carried out by dilution of oil samples with 2-propanol. Tyrosol, which was contained at relatively high concentration in virgin olive oil among phenolic compounds, was determined by HPLC after a simple liquid-liquid extraction. When using squalene and tyrosol contents as axes, extra virgin olive oils could be discriminated from pure olive oils, blended oils (extra virgin olive oils with sunflower oil or grapeseed oil) and other vegetable oils. These results suggest that determining squalene and tyrosol in seed oil samples could be useful in distinguishing between extra virgin olive oil and blended oils as a screening method.


Assuntos
Análise de Alimentos/métodos , Contaminação de Alimentos/análise , Contaminação de Alimentos/prevenção & controle , Qualidade dos Alimentos , Azeite de Oliva/análise , Azeite de Oliva/química , Álcool Feniletílico/análogos & derivados , Esqualeno/análise , Cromatografia Líquida de Alta Pressão , Extração Líquido-Líquido/métodos , Álcool Feniletílico/análise , Óleos Vegetais/análise
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