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1.
J Hosp Infect ; 141: 167-174, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37696472

RESUMO

BACKGROUND: Different isolation measures are required according to the routes of transmission of pathogens. Few studies have compared different forms of hygiene training in terms of efficiency and/or improvement of perception towards hygiene measures. This study aimed to evaluate the benefits of different forms of isolation training in the operating room, and their respective effects on the perception of hygiene measures by comparing simulation training with video-based training. METHODS: This multi-centre, prospective, randomized, controlled trial compared hygiene knowledge, psychological safety and perception of training among healthcare workers after in-centre simulation training and conventional video-based training. RESULTS: Neither type of training led to a significant improvement in knowledge or perceived psychological safety (F=0.235, P=0.629, η2=0.003). Participants in the simulation group reported higher levels of willingness to speak up in the depicted scenario compared with participants who received video-based training. Participants perceived the simulation-based training significantly more positively than the video-based training. CONCLUSION: Clear definition of the goals of training based on the pre-existing level of knowledge of the participants is crucial. For future studies, it would be interesting to investigate the long-term effect and continuing benefits concerning the implementation of hygiene regulations after different types of training.


Assuntos
Salas Cirúrgicas , Treinamento por Simulação , Humanos , Estudos Prospectivos , Pessoal de Saúde , Higiene
2.
J Hosp Infect ; 135: 163-170, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36907335

RESUMO

BACKGROUND: Anaesthesia induction is a fast-paced, complex activity that involves a high density of hand-to-surface exposures. Hand hygiene (HH) adherence has been reported to be low, which bears the potential for unnoticed pathogen transmission between consecutive patients. AIM: To study the fit of the World Health Organization's (WHO) five moments of HH concept to the anaesthesia induction workflow. METHODS: Video recordings of 59 anaesthesia inductions were analysed according to the WHO HH observation method considering each hand-to-surface exposure of every involved anaesthesia provider. Binary logistic regression was used to determine risk factors for non-adherence, i.e. professional category, gender, task role, gloves, holding of objects, team size and HH moment. Additionally, half of all videos were recoded for quantitative and qualitative analysis of provider self-touching. FINDINGS: Overall, 2240 HH opportunities were met by 105 HH actions (4.7%). The drug administrator role (odds ratio (OR): 2.2), the senior physician status (OR: 2.1), donning (OR: 2.6) and doffing (OR: 3.6) of gloves were associated with higher HH adherence. Notably, 47.2% of all HH opportunities were caused by self-touching behaviour. Provider clothes, face, and patient skin were the most frequently touched surfaces. CONCLUSION: The high density of hand-to-surface exposures, a high cognitive load, prolonged glove use, carried mobile objects, self-touching, and personal behaviour patterns were potential causes for non-adherence. A purpose-designed HH concept based on these results, involving the introduction of designated objects and provider clothes to the patient zone, could improve HH adherence and microbiological safety.


Assuntos
Anestesia , Infecção Hospitalar , Higiene das Mãos , Médicos , Humanos , Higiene das Mãos/métodos , Controle de Infecções/métodos , Organização Mundial da Saúde , Fidelidade a Diretrizes , Infecção Hospitalar/prevenção & controle , Pessoal de Saúde
3.
J Agric Food Chem ; 69(39): 11592-11605, 2021 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-34550684

RESUMO

The INFOGEST standardized method was applied to assess the potential bioaccessibility and bioaccessibility of the phenolic compounds from a Galician extra-virgin olive oil (EVOO). The in vitro digestion model involves three steps and generates two fractions after each one: an aqueous fraction (namely, water phase (Wp)) and an oily fraction (namely, oily phase (Op)). The results showed that secoiridoids were the most abundant family in the Galician EVOO polar fraction, representing 98% of the total phenolic compounds. After oral digestion, phenolic acids and simple phenols were mainly detected in Wp, while lignans and flavonoids were mostly found in Op. After gastric digestion, extensive hydrolysis of secoiridoids was observed to generate free tyrosol, hydroxytyrosol, and hydroxytyrosol acetate. The instability of secoiridoids after intestinal digestion was again responsible for the release of simple phenols, which were mainly recovered in Wp together with flavonoids. In contrast, lignans were stable to duodenal conditions and remained in Op.


Assuntos
Fenóis , Óleos de Plantas , Flavonoides , Iridoides , Azeite de Oliva , Fenóis/análise
4.
Food Res Int ; 137: 109427, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-33233109

RESUMO

The diet management is imperative to anticipate risk factors that favour the development of diseases; indeed, the intake of virgin olive oil could be an alternative natural source of α-glucosidase enzyme inhibitors, which delay the digestion rate of carbohydrates. Consequently, the impact of diabetes mellitus (DM) could be diminished. Extra Virgin Olive Oils (EVOO) were elaborated from Galician autochthonous variety 'Brava Gallega' with olives selected at three different degree of ripeness (ripening index, RI: 1.4, 3.0, 5.5) in order to assess the effect of maturation on overall chemical composition, sensory quality, and enzyme inhibition. The phenolic profile of the EVOOs determined by LC-ESI-IT-MS exhibited quantitative differences as ripening advanced; for example oleocanthal, tyrosol, luteolin and apigenin concentrations were higher in the overripe olive oil (RI 5.5). Anyway, the phenolic extracts (from every tested RI) were more active than acarbose. In particular, those obtained from the most mature olives displayed the most powerful inhibitory activity (IC50 value of 143 µg of dry extract/mL). In addition, the significant effect of these compounds (i.e. luteolin, apigenin, tyrosol and oleocanthal) on the inhibitory activity of the olive oil extracts was demonstrated. Our results suggest that, regardless of RI, the inhibitory activity of 'Brava Gallega' olive oils could represent a valuable strategy for reinforcing the health claim of olive oil for phenolic compounds.


Assuntos
Hipoglicemiantes , Olea , Hipoglicemiantes/farmacologia , Azeite de Oliva , Extratos Vegetais/farmacologia , Óleos de Plantas
5.
Food Res Int ; 130: 108930, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32156378

RESUMO

The influence of antifungal tetraconazole residues (either as an active substance or as a commercial formulation product) on the fermentative activity of Saccharomyces cerevisiae yeast was evaluated in pasteurized Garnacha red must by using laboratory-scale fermentation assays. The presence of this fungicide promoted a slight decrease in glucose consumption. Volatile fermentative-derived compounds were evaluated in deep. Statistically significant changes were found in methionol (with a mean decrease of around 24%), fatty acids (with increments ranged from 23% to 66%), and ethyl esters (with increases ranged from 23% to 145%) contents when grape musts were enriched with the commercial formulation at both contamination levels assayed. Based on protein mass fingerprinting analysis, it was possible to relate these variations on volatiles content with changes in the activity of several enzymes (Met3p, Met14p, Adh2p, Hmg1p, Erg5p, Erg6p, Erg11p, and Erg20p) involved in the secondary metabolism of yeasts.


Assuntos
Clorobenzenos/metabolismo , Ergosterol/metabolismo , Fungicidas Industriais/metabolismo , Metionina/metabolismo , Saccharomyces/metabolismo , Triazóis/metabolismo , Compostos Orgânicos Voláteis/metabolismo
6.
Food Res Int ; 126: 108566, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31732059

RESUMO

The impact of mepanipyrim (Mep) and its corresponding commercial formulation (Mep Form) on Saccharomyces cerevisiae metabolites was assessed, separately, by using laboratory-scale wine fermentation assays on pasteurized red must. The presence of Mep did not alter the fermentation course. With regard to volatiles formed at the intracellular level by fermenting yeast cells, Mep residues affected mainly the acetate and ethyl ester biochemical pathways. In particular, the target acetates showed a notorious increment, >90%, in presence of commercial Mep Form at the higher dose assayed. The addition of Mep and Mep Form, at both tested levels, highly increased ethyl caprylate (between 42 and 63%) and ethyl caprate (between 36 and 60%) contents as the same as their respective fatty acid precursors. No important effects were observed on colour and non-volatile pyranoanthocyanins, probably due to the low anthocyanin content characteristic of pasteurized musts.


Assuntos
Pirimidinas/análise , Saccharomyces cerevisiae/metabolismo , Vinho/análise , Acetatos/análise , Antocianinas/análise , Caprilatos/química , Cor , Fermentação , Análise de Alimentos , Pasteurização , Vitis/química , Compostos Orgânicos Voláteis/análise
7.
Food Res Int ; 116: 447-454, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30716967

RESUMO

'Brava' and 'Mansa de Figueiredo' extra-virgin olive oils (EVOOs) are two varieties identified from north-western Spain. A systematic phenolic characterization of the studied oils was undertaken by LC-ESI-IT-MS. In addition, the role of dietary polyphenols from these EVOOs has been evaluated against the inhibition of key enzymes (α-glucosidase and α-amylase) in the management of diabetes mellitus (DM). Oleuropein and ligstroside derivatives comprised 83% and 67% of the total phenolic compounds in 'Brava' and 'Mansa de Figueiredo' EVOOs, respectively. The main secoiridoids from oleuropein were DOA (3,4-DHPEA-EDA, 59 and 22 mg kg-1, respectively) and the main isomer of OlAgl (3,4-DHPEA-EA, 74 and 23 mg kg-1). The main secoiridoids from ligstroside were D-LigAgl (p-HPEA-EDA or oleocanthal, 23 and 167 mg kg-1) and the main isomer of LigAgl (p-HPEA-EA, 214 and 114 mg kg-1). For α-glucosidase, both EVOO extracts displayed stronger inhibitory activity (IC50 values of 60 ±â€¯8 and 118 ±â€¯9 µg mL-1, respectively) than the commercial inhibitor acarbose (IC50 = 356 ±â€¯21 µg mL-1). Nevertheless, for α-amylase, only 'Brava' extracts showed anti-α-amylase capacity. A daily VOO intake lower than the requirements of EFSA seem to be enough to reach both 50% for α-glucosidase and 25% for α-amylase inhibition. These findings support the potential health benefits derived from Galician EVOOs that might be probably linked to the outstanding high concentration levels of phenolic acids and flavonoids.


Assuntos
Azeite de Oliva/química , Extratos Vegetais/análise , Extratos Vegetais/farmacologia , alfa-Amilases/efeitos dos fármacos , alfa-Glucosidases/efeitos dos fármacos , Aldeídos/análise , Monoterpenos Ciclopentânicos/análise , Diabetes Mellitus Tipo 2 , Flavonoides , Glucosídeos/análise , Inibidores de Glicosídeo Hidrolases/farmacologia , Hipoglicemiantes/farmacologia , Glucosídeos Iridoides , Iridoides/análise , Fenóis/análise , Fenóis/farmacologia , Piranos/análise , Espanha
8.
Food Res Int ; 106: 558-567, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29579961

RESUMO

In this work, phenol-rich extracts from 'Cornicabra' and 'Picual' virgin-olive oils (EVOOs) were examined, for the first time, to establish their capacity to inhibit key enzymes involved in Alzheimer's disease (AD) (acetylcholinesterase (AChE), butyrylcholinesterase (BuChE) and 5-lipoxygenase (LOX)), major depressive disorder (MDD) and Parkinson's disease (PD) (monoamine oxidases: hMAO-A and hMAO-B respectively), and diabetes mellitus (DM) (α-glucosidase and α-amylase). 'Cornicabra' displayed the best inhibitory activity against all enzymes, when compared to 'Picual': BuChE (IC50 = 156 ±â€¯4 and 308 ±â€¯33 mg mL-1), LOX (IC50 = 26 ±â€¯0.5 and 37 ±â€¯3 mg mL-1), hMAO-A (IC50 = 20 ±â€¯2 and 37 ±â€¯0.2 mg mL-1), hMAO-B (IC50 = 131 ±â€¯7 and 215 ±â€¯13 mg mL-1) and α-glucosidase (IC50 = 154 ±â€¯17 and 251 ±â€¯31 mg mL-1), respectively. The behaviour observed can be associated with the higher content of secoiridoids, lignans and phenolic acids in 'Cornicabra' EVOO.


Assuntos
Inibidores de Glicosídeo Hidrolases/farmacologia , Fármacos Neuroprotetores/farmacologia , Azeite de Oliva/química , Fenóis/farmacologia , Acetilcolinesterase/metabolismo , Antidepressivos/isolamento & purificação , Antidepressivos/farmacologia , Antioxidantes/isolamento & purificação , Antioxidantes/farmacologia , Antiparkinsonianos/isolamento & purificação , Antiparkinsonianos/farmacologia , Araquidonato 5-Lipoxigenase/metabolismo , Butirilcolinesterase/metabolismo , Inibidores da Colinesterase/isolamento & purificação , Inibidores da Colinesterase/farmacologia , Relação Dose-Resposta a Droga , Inibidores de Glicosídeo Hidrolases/isolamento & purificação , Inibidores de Lipoxigenase/isolamento & purificação , Inibidores de Lipoxigenase/farmacologia , Monoaminoxidase/metabolismo , Inibidores da Monoaminoxidase/isolamento & purificação , Inibidores da Monoaminoxidase/farmacologia , Fármacos Neuroprotetores/isolamento & purificação , Azeite de Oliva/classificação , Fenóis/isolamento & purificação , alfa-Amilases/antagonistas & inibidores , alfa-Amilases/metabolismo , alfa-Glucosidases/metabolismo
9.
Artigo em Inglês | MEDLINE | ID: mdl-26424608

RESUMO

A study was undertaken to evaluate dietary glutamine supplementation effects on gilthead sea bream performance, intestinal nutrient absorption capacity, hepatic and intestinal glutamine metabolism and oxidative status. For that purpose gilthead sea bream juveniles (mean weight 13.0g) were fed four isolipidic (18% lipid) and isonitrogenous (43% protein) diets supplemented with 0, 0.5, 1 and 2% glutamine for 6weeks. Fish performance, body composition and intestinal nutrient absorption capacity were not affected by dietary glutamine levels. Hepatic and intestinal glutaminase (GlNase), glutamine synthetase (GSase), alanine aminotransferase, aspartate aminotransferase and glutamate dehydrogenase activities were also unaffected by dietary glutamine supplementation. In the intestine GlNase activity was higher and GSase/GlNase ratio was two-fold lower than in the liver, suggesting a higher use of glutamine for energy production by the intestine than by the liver. The liver showed higher catalase and glucose-6-phosphate dehydrogenase activities, while the intestine presented higher glutathione peroxidase and glutathione reductase activities and oxidised glutathione content, which seems to reveal a higher glutathione dependency of the intestinal antioxidant response. Total and reduced glutathione contents in liver and intestine and superoxide dismutase activity in the intestine were enhanced by dietary glutamine, though lipid peroxidation values were not affected. Overall, differences between liver and intestine glutamine metabolism and antioxidant response were identified and the potential of dietary glutamine supplementation to gilthead sea bream's antioxidant response was elucidated.


Assuntos
Aminoácidos/metabolismo , Antioxidantes/farmacologia , Suplementos Nutricionais , Alimentos , Glutamina/farmacologia , Absorção Intestinal/efeitos dos fármacos , Dourada/metabolismo , Animais , Arginina/metabolismo , Dieta , Glucose/metabolismo , Glutamina/metabolismo , Glutationa/metabolismo , Intestinos/efeitos dos fármacos , Intestinos/enzimologia , Peroxidação de Lipídeos/efeitos dos fármacos , Fígado/efeitos dos fármacos , Fígado/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Dourada/crescimento & desenvolvimento
10.
Food Chem ; 176: 493-503, 2015 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-25624261

RESUMO

The current trend of the olive oil market is the production of high quality extra from traditional minor olive varieties with peculiar and differentiated characteristics (especially with respect to the aromatic and phenolic composition). In this way, the interest of Galician oil producers (NW Spain) in recovering old autochthonous Local olive fruits has increased substantially in recent years. In order to investigate the potential of the Local olives by either producing high quality monovarietal oils or mixing with the most widespread olives in Galicia (Arbequina and Picual cv.), quality indices, and fatty acid composition as well as volatile and phenolic profiles were determined and compared. All EVOOs studied in this work can be considered as "extra virgin olive oil" due to quality indices fell within the ranges established in legislation. Picual and Local olive oils as well as those resulting from their co-crushing reach values which are required by EU legislation to add the specific health claim on the oil label. Co-crushing Picual:Local (80:20) provided a significant enhancement of grass and apple nuances and a decrease of banana notes with respect to Picual oils. The co-crushing process improved sensory and health properties of Picual extra virgin olive oils. The effect of co-crushing on phenolics, ester volatiles and banana nuances cannot be easily modulated, contrary to quality indices and fatty acid composition, both changing linearly in strict correlation with the fruit mass ratio.


Assuntos
Olea/química , Fenóis/análise , Óleos de Plantas/análise , Ácidos Graxos , Azeite de Oliva , Óleos de Plantas/química , Compostos Orgânicos Voláteis
11.
Food Chem ; 164: 418-26, 2014 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-24996353

RESUMO

Systematic studies of physico-chemical and stability-related properties, and chemical composition, of extra virgin olive oils (EVOOs) obtained from drupes cropped in specific regions are of special agricultural interest. This is particularly so with new production areas, where careful selection of the most suitable olive varieties for EVOO production is required. This paper reports the first comprehensive chemical characterisation of EVOOs obtained from three different olive varieties (viz., Picual, Morisca and Manzanilla de Sevilla) grown in a new cultivation area in Galicia (NW Spain). The Morisca variety was that providing the highest industrial oil yield (21%). However, the three types of EVOO exhibited no statistically significant differences in standard quality-related indices other than acidity. Morisca EVOO was that with the lowest content in oleic acid (mean=68%) and highest content in linoleic acid (mean=13%). Also, Morisca EVOO exhibited the highest sterol levels (mean=1,616 mg/kg) and Picual EVOO the lowest (mean=1,160 mg/kg). Picual EVOO contained greater amounts of the phenolic compounds luteolin and pinoresinol than both Morisca and Manzanilla de Sevilla EVOOs. Finally, Manzanilla de Sevilla EVOO exhibited differential attributes, with banana and olive fruit aromatic series prevailing predominantly over bitter-like, pungent-like and leaf series.


Assuntos
Qualidade dos Alimentos , Frutas/química , Olea/química , Óleos de Plantas/análise , Óleos de Plantas/normas , Frutas/crescimento & desenvolvimento , Furanos/análise , Lignanas/análise , Olea/crescimento & desenvolvimento , Ácido Oleico/análise , Azeite de Oliva , Fenóis/análise , Espanha , Paladar
12.
Anaesthesia ; 69(5): 452-7, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24738802

RESUMO

We analysed the results of the first phase of the Zurich Unexpected Difficult Airway course. Two hundred and twenty-eight staff members performed a total of 2712 standardised airway rescue procedures with four airway devices: SensaScope™, LMA Fastrach™, Laryngeal Tube and needle cricothyrodotomy. Four consecutive attempts were performed using each device. We analysed the success rate and the time needed for successful completion for each attempt and device. The success rates and mean (SD) completion times for all participants were 96.2% and 30.2 (15.3) s for the SensaScope, 88.1% and 40.4 (17.2) s for the LMA Fastrach, 99.0% and 12.1 (10.6) s for the Laryngeal Tube and 99.0% and 12.3 (6.1) s for needle cricothyroidotomy. The learning curves resulting from the four consecutive attempts with each device showed a clear pattern of improvement. This institutional airway training course represents a promising method to improve the capability of practitioners to cope with unexpected difficult airway situations.


Assuntos
Anestesiologia/educação , Competência Clínica/estatística & dados numéricos , Capacitação em Serviço/métodos , Intubação Intratraqueal/instrumentação , Intubação Intratraqueal/métodos , Avaliação de Programas e Projetos de Saúde/métodos , Adulto , Desenho de Equipamento , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Avaliação de Programas e Projetos de Saúde/estatística & dados numéricos
13.
Food Chem ; 158: 534-45, 2014 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-24731380

RESUMO

The influence of olive paste preparation conditions on the standard quality parameters, as well as volatile profiles of extra virgin olive oils (EVOOs) from Morisca and Manzanilla de Sevilla cultivars produced in an emerging olive growing area in north-western Spain and processed in an oil mill plant were investigated. For this purpose, two malaxation temperatures (20/30 °C), and two malaxation times (30/90 min) selected in accordance with the customs of the area producers were tested. The volatile profile of the oils underwent a substantial change in terms of odorant series when different malaxation parameters were applied.


Assuntos
Odorantes/análise , Olea/química , Fenóis/análise , Óleos de Plantas/química , Análise dos Mínimos Quadrados , Azeite de Oliva , Análise de Regressão , Reprodutibilidade dos Testes , Espanha , Temperatura , Volatilização
14.
Food Chem ; 152: 522-30, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24444970

RESUMO

A natural sweet wine (NSW) was made with dried grapes from Vitis vinifera L. cv Garnacha Tintorera. A fortified sweet wine (FSW) was also obtained: the maceration-alcoholic fermentation of Garnacha Tintorera must was stopped by addition of ethanol 96% (v/v). UV/Vis spectrophotometry and HPLC/DAD-ESI/MS were applied to determine, respectively, the evolution of colour and phenolic compounds in Garnacha Tintorera based-sweet wines during aging. In sweet wines, aging decreased a(∗) (red/green), colour saturation and lightness and increased b(∗) (yellow/blue), and hue angle. Most of the phenolic compounds determined, such as anthocyanins, esters of hydroxycinnamic acids, flavan-3-ols monomers, oligomers and polymers decreased in both sweet wines during aging. On the contrary, hydroxybenzoic and hydroxycinnamic acids and vitisins increased after one year of aging. Despite that both terminal and extension subunit compositions show very small changes, mean degree of polymerisation of proanthocyanidins decline slightly as aging progressed in both sweet wines.


Assuntos
Manipulação de Alimentos/instrumentação , Fenóis/química , Quercus/química , Vitis/química , Vinho/análise , Antocianinas/análise , Cor , Armazenamento de Alimentos , Espectrofotometria , Fatores de Tempo
15.
Food Chem ; 150: 128-36, 2014 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-24360429

RESUMO

A reliable, sensitive and effective method based on ultrasound-assisted emulsification-microextraction (USAEME) coupled to HPLC-DAD has been developed to identify and quantify several target phenolic compounds from extra virgin olive oils (EVOO). This approach is based on the emulsification of a microvolume of polar organic extractant in a non-polar liquid sample by ultrasound radiation and further separation of both liquid phases by centrifugation. The percentage of methanol/water (v/v) in the extractant, the volume of extractant, and the extraction time as three effective parameters on the extraction were optimised by a central composite design (Box-Behnken response surface) method. The optimised method presented recoveries in EVOO between 91% and 115% for the target analytes (except vanillin with 65%) and a satisfactory precision with relative standard deviations (RSD%) lower than 8.4% for repeatability and reproducibility. The method showed good linearity and limits of detection and quantification were in the range 0.001-0.14 and 0.004-0.47mg/kg, respectively. After method validation, it was successfully applied to the analysis of three EVOO samples. All target compounds were detected in all analysed samples. Tyrosol and hydroxytyrosol were the major phenolic compounds, followed by pinoresinol and luteolin.


Assuntos
Microextração em Fase Líquida/métodos , Fenóis/isolamento & purificação , Óleos de Plantas/química , Ultrassom/métodos , Limite de Detecção , Azeite de Oliva , Fenóis/análise
16.
Food Chem ; 146: 234-41, 2014 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-24176337

RESUMO

The influence of ten new generation fungicides (ametoctradin, benthiavalicarb-isopropyl, boscalid, cyazofamid, dimethomorph, fenhexamid, kresoxim-methyl, mepanipyrim, metrafenone, and pyraclostrobin) on the fermentative activity of Saccharomyces cerevisiae yeast was initially evaluated in pasteurised red must. The presence of ametoctradin, dimethomorph and mepanipyrim seemed to affect sugars-to-ethanol yield in the stationary phase. The same fermentation experiments were carried out for these three fungicides in ecological red must from Vitis vinifera cv. Tempranillo. When ecological must was unfiltered, the fermentative activity of yeasts was unaffected by the presence of these selected fungicides. However, when ecological must was filtered beforehand, a slight decrease of biomass and ethanol production (in terms of biomass-to-ethanol yield and sugars-to-ethanol yield, respectively), as well as a decrease in fruity aroma, were registered with respect to the control wine.


Assuntos
Fungicidas Industriais/farmacologia , Saccharomyces cerevisiae/efeitos dos fármacos , Saccharomyces cerevisiae/crescimento & desenvolvimento , Vitis/microbiologia , Compostos Orgânicos Voláteis/análise , Vinho/análise , Etanol/análise , Etanol/metabolismo , Fermentação/efeitos dos fármacos , Saccharomyces cerevisiae/metabolismo , Vitis/metabolismo , Compostos Orgânicos Voláteis/metabolismo , Vinho/microbiologia
17.
Food Chem ; 143: 282-92, 2014 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-24054241

RESUMO

Sweet wines are traditionally elaborated in Galicia (the N.W. corner of Spain). The denomination of origin (DO) Valdeorras, one of the five DOs in Galicia, wants to promote the production and marketing of new sweets wines. The first one is made with dried red grapes Vitis vinifera L. Garnacha Tintorera (GNSW); this cultivar is a teinturier cultivar which has excellent potential to produce wines from raisined grapes. The second one, a fortified sweet wine aged in oak barrels (GFSW). Additionally a dry young wine (GBW) was produced from the same variety. Their aroma profiles and chromatic characteristics (determined by simple spectrophotometric methods) have been previously established. Now, proanthocyanidins, flava-3-ol monomers, anthocyanins, phenolic acids, flavonols and resveratrol were determined by HPLC, for the same three wines. The highest concentration of total proanthocyanidins (PAs) was evaluated in the GBW (525mgL(-1)), which was about 2-fold the concentration in the GNSW (236mgL(-1)) and about more 10-fold the concentration in the GFSW (44mgL(-1)). No apparent difference in the aDP (mean degree of polymerisation) was observed for the GBW (1.9) and the GNSW (2.1), whereas a slightly lower value was obtained for the GFSW (1.5). Total anthocyanin concentration was described as follow as GBW: 390mgL(-1)≫GNSW: 57mgL(-1)>GFSW: 25mgL(-1), which indicates that sweet wines were polymerised in great extent. Only vitisin A and B were found the main concentration in GFSW when compared to GBW by the ageing process. In sweet wines, phenolic acids (hydroxybenzoic and hydroxycinnamic acids) and flavonols were lowest when compared to GBW and resveratrol not was found in sweet wines.


Assuntos
Fenóis/química , Vinho/análise , Cromatografia Líquida de Alta Pressão , Humanos , Espanha , Espectrometria de Massas por Ionização por Electrospray , Paladar
18.
Food Chem ; 141(3): 3230-40, 2013 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-23871082

RESUMO

The off-vine drying is one of the most important steps in the production of a high quality naturally sweet wine. However, only few studies have analyzed the changes in colour and phenolic compounds of the grapes throughout the process. In this work, UV/Vis spectrophotometry and HPLC/DAD-ESI/MS were applied to determine, respectively, the evolution of colour and phenolic compounds in the red grapes of Garnacha Tintorera during the raisining process. The total water loss in 83 days was about 62% and the sugar concentration rose from 225 to 464 g L(-1). Browning and low-medium molecular weight compounds increase during the dehydration process. In CIELab coordinates, raisining decreases a(*) (red/green) and lightness and increases b(∗) (yellow/blue), colour saturation and hue angle. In general, most of the phenolic compounds determined (anthocyanins, flavonols, esters of hydroxycinnamic acids, flavan-3-ol monomers and proanthocyanidins) increase but to a lesser extent than expected because of the water loss of the grapes during drying. The lower increase was observed for esters of hydroxicinnamic acids suggesting these compounds could undergo strong enzymatic degradation. Despite this, both the terminal and the extension subunit compositions show little changes, while the mean degree of polymerization of proanthocyanidins decreases as raisining progresses.


Assuntos
Frutas/química , Fenóis/análise , Vitis/química , Carboidratos/análise , Cromatografia Líquida de Alta Pressão , Cor , Dessecação , Manipulação de Alimentos , Espectrometria de Massas por Ionização por Electrospray , Vinho/análise
19.
Food Chem ; 141(1): 637-43, 2013 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-23768404

RESUMO

The two constitutive parts of four cultivars (Arbequina, Picual, Local and Manzanilla de Sevilla) grown in Spain were separately analysed in order to establish the role of pulp and seed in the biogenesis of extra virgin olive oil (EVOO) aroma through the lipoxygenase (LOX) pathway. C6 and C5 volatile compounds responsible of EVOO aroma were produced by endogenous enzymes in both parts of olive fruits and the differences can be attributed to different enzymes distribution in pulp and seed. According to results, C6 and C5 volatile compounds have mainly their biogenesis in pulp (80-90%) vs. seed (20-10%), independently of the cultivar considered. A linear discriminant analysis was used to establish discriminant aroma compounds between pulp and seed related to the maturity index. A decrease in trans-2-hexen-1-al and an increase in 1-hexanol with ripeness were observed independently of the cultivar considered. Finally, Partial Least Squares (PLS) regression analysis between pulp and seed aroma compounds allowed to establish those volatile compounds that better describe each cultivar.


Assuntos
Olea/química , Olea/classificação , Extratos Vegetais/química , Compostos Orgânicos Voláteis/química , Frutas/química , Frutas/classificação , Cromatografia Gasosa-Espectrometria de Massas , Odorantes/análise , Azeite de Oliva , Óleos de Plantas/química , Espanha
20.
Food Chem ; 140(1-2): 217-24, 2013 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-23578636

RESUMO

Valdeorras (the N.W. corner of Spain) wants to promote the production and marketing of new sweet wines. The present work represents the first study on sweet wines manufactured with red grapes Vitis vinifera L. Garnacha Tintorera, a teinturier cultivar. Two different red sweet wines were elaborated: the first one was made with dried grapes; Vitis vinifera L. Garnacha Tintorera has excellent potential to produce wines from raisined grapes; the second one, a fortified sweet wine aged in oak barrels. Different red Garnacha Tintorera-based wines (a dry base wine, GBW; a naturally sweet wine, GNSW; and a fortified sweet wine, GFSW) were characterized. Chromatic characteristics and phenolic compounds were established by spectrophotometric methods in order to assess the technology of Garnacha Tintorera-based sweet wines. High molecular weight brown polymers, produced during the grape drying process and isolated from sweet wines by the dialysis process, were responsible for the brown colour of sweet wines. As a consequence, yellowness of sweet wines was also higher which was confirmed by colorimetric indexes. With respect to phenolic content, GFSW presented the lowest content because the maceration-alcoholic fermentation was stopped through the addition of alcohol before the diffusion of red pigments from skins to must was complete. GNSW presented the highest phenolic content due to the concentration effect resulting from evaporation of water from the grapes. Anthocyanins of sweet wines were polymerised in great extent. The percentage of polymerised tannins was sufficient to guarantee the aging process of sweet wines.


Assuntos
Fenóis/química , Espectrofotometria/métodos , Vitis/química , Vinho/análise , Antocianinas/análise , Aromatizantes/química , Espanha , Taninos/análise
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