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1.
BMC Psychol ; 11(1): 407, 2023 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-37990335

RESUMO

BACKGROUND: Compulsivity is the hallmark of addiction progression and, as a construct, has played an important role in unveiling the etiological pathways from learning mechanisms underlying addictive behavior to harms resulting from it. However, a sound use of the compulsivity construct in the field of behavioral addictions has been hindered to date by the lack of consensus regarding its definition and measurement. Here we capitalize on a previous systematic review and expert appraisal to develop a compulsivity scale for candidate behavioral addictions (the Granada Assessment for Cross-domain Compulsivity, GRACC). METHODS: The initial scale (GRACC90) consisted of 90 items comprising previously proposed operationalizations of compulsivity, and was validated in two panel samples of individuals regularly engaging in gambling and video gaming, using exploratory structural equation modeling (ESEM) and convergence analyses. RESULTS: The GRACC90 scale is unidimensional and structurally invariant across samples, and predicted severity of symptoms, lower quality of life, and negative affect, to similar degrees in the two samples. Additionally, poorer quality of life and negative affect were comparably predicted by compulsivity and by severity of symptoms. A shorter version of the scale (GRACC18) is proposed, based on selecting the 18 items with highest factor loadings. CONCLUSIONS: Results support the proposal that core symptoms of behavioral addictions strongly overlap with compulsivity, and peripheral symptoms are not essential for their conceptualization. Further research should clarify the etiology of compulsive behavior, and whether pathways to compulsivity in behavioral addictions could be common or different across domains.


Assuntos
Comportamento Aditivo , Jogo de Azar , Jogos de Vídeo , Humanos , Qualidade de Vida , Comportamento Compulsivo
2.
Food Chem ; 346: 128919, 2021 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-33418420

RESUMO

The post-fermentative double addition of Pedro Ximénez cv seeds obtained from natural matured grapes (ripe seeds, RS) and postharvest sun-dried grapes (overripe seeds, OS) were studied as sustainable enological alternatives to conventional vinification (CW) to improve the stability of Syrah wines produced in a warm climate. The phenolic composition was assessed by rapid resolution liquid chromatography, copigmentation/polymerization processes by spectrophotometry, and color quality and stability by Differential Colorimetry. OSW and RSW wines enriched their total phenolic content, being the effect more pronounced with overripe seeds (by 23% versus 10%). OSW differences were found for gallic acid, monomeric flavan-3-ols, and procyanidins compared to CW, and for (+)-catechin, procyanidin B2-3-O-gallate and the tetramer to RSW. Phenolic changes were related to higher color intensity in seed-added wines. OSW having higher percentage of polymeric pigments maintained for longer time the chromatic improvement, being visually darker and more intense than final CW and RSW.


Assuntos
Clima , Cor , Fermentação , Fenóis/análise , Vinho/análise , Sementes/química , Vitis/química
3.
Foods ; 10(3)2021 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-33668279

RESUMO

Overripe seeds from sun-dried grapes submitted to postharvest dehydration constitute a scarcely investigated class of vinification byproduct with limited reports on their phenolic composition and industrial applications. In this study, Raman spectroscopy was applied to characterize a selection of overripe seed byproducts from different white grapes (cv. Moscatel, cv. Pedro Ximénez and cv. Zalema) submitted to postharvest sun drying. The Raman measurements were taken using a 1064 nm excitation laser in order to mitigate the fluorescent effect and the dispersive detection scheme allowed a compactness of the optical system. Spectroscopic data were processed by a principal component analysis to reduce the dimensionality and partner recognition. The evolution of the Raman spectrum during the overripening process was compared with the phenolic composition of grape seeds, which was determined by rapid resolution liquid chromatography/mass spectrometry (RRLC/MS). A multivariate processing of the spectroscopic data allowed the classification of overripe seeds according to the grape variety and the monitoring of stages of the postharvest sun drying process.

4.
Food Chem ; 272: 329-336, 2019 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-30309551

RESUMO

With the purpose of modulating the copigmentation equilibria of red wines, an environmentally sustainable process was performed based on post-fermentative addition of overripe seeds (OS). Simple (SW) and double (DW) addition were performed to produce different enrichment of phenolics from seeds, hence different copigmentation/polymerization ratios. The determination of the phenolic composition showed different global increases in OS-macerates wines (catechin, epicatechin, gallic acid and procyanidins B1 and B2). The double post-maceration (DW) was more effective than the simple post-maceration addition to improve the phenolic structure of wines. The application of Differential Tristimulus Colorimetry could assess the effects of this practice on the color characteristics and stability of wines. Results highlighted that both simple and double assays underwent colorimetric improvements against the control wines (CW, no seeds addition). DW led to the highest chromatic stability, showing lower lightness, higher chroma values and bluish hues than CW. This color difference was visually detectable.


Assuntos
Fermentação , Sementes/química , Vinho/análise , Vinho/microbiologia , Cor , Ácido Gálico/análise , Fenóis/análise , Sementes/crescimento & desenvolvimento , Vitis/química , Vitis/crescimento & desenvolvimento
5.
J Agric Food Chem ; 67(14): 4031-4042, 2019 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-30892885

RESUMO

The increase of temperature can cause a decoupling of sugar and anthocyanin accumulation in grapes, leading to wines poor in color. Different enological techniques are nowadays under study to overcome this problem. Among them, the present study has evaluated the color and pigment composition modifications caused by the addition during Syrah winemaking of either Pedro Ximénez seeds (intended to increase chemical stability) or/and two different mannoproteins (color-protective and astringency-modulator) to increase colloidal stability. Color and pigment composition modifications were assessed from CIELAB color parameters and from HPLC-DAD-MS n results before and after cold-treatment (used to force colloidal instability). The addition of both seeds and mannoproteins increased color stability against cold and, additionally, against SO2-bleaching in the case of mannoproteins. However, the initial pigment composition and color of the samples were differently affected by these additions, being clearly affected (Δ E* ab > 3) in the cases of seeds and with the astringency-modulator mannoprotein and hardly modified with the other one.


Assuntos
Aditivos Alimentares/química , Manipulação de Alimentos/métodos , Glicoproteínas de Membrana/química , Pigmentos Biológicos/química , Sementes/química , Vitis/química , Vinho/análise , Cor , Fermentação , Aditivos Alimentares/metabolismo , Glicoproteínas de Membrana/metabolismo , Pigmentos Biológicos/metabolismo , Saccharomyces cerevisiae/metabolismo , Vitis/metabolismo , Vitis/microbiologia , Vinho/microbiologia
6.
Food Res Int ; 126: 108650, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31732037

RESUMO

One of the main consequences of the advancement of harvest date associated to global climate change is that the phenolic maturity of grapes can be delayed in relation to their technological maturity. As a consequence, wines made from these grapes can be poor in phenolic compounds or possess an unbalanced phenolic composition, affecting their global quality. The combined post-fermentative addition of seeds and an astringency-modulator mannoprotein (MP) might be a potential strategy to solve this problem, since seeds might supply flavanols and improve wine chemical stability and the mannoprotein might modulate the changes induced in astringency by the addition of seeds and improve wine colloidal stability. The present study aimed at monitoring at different moments of winemaking and ageing the effects and side-effects of this combined strategy on the detailed flavanol, flavonol and anthocyanin compositions and on colour of wines made from Syrah grapes. Seeds were obtained from Pedro Ximénez overripe grapes. Flavanol composition and flavonol and anthocyanin compositions were determined by HPLC-MSn-MRM and HPLC-DAD-MSn analyses, respectively. Colour changes caused by these additions were studied from CIELAB parameters as well as the ability of these techniques to protect colour from bleaching agents, such as SO2. In general, the addition of seeds initially increased the levels of flavanols and anthocyanins. However, during bottle ageing a reduction in the levels of flavanols, flavonols and anthocyanins could be observed in seed treated wines, which might be related to the greater formation of flavanol aggregates associated with greater levels of flavanols. This effect was partially solved for most of the flavonoids studied with the additional MP treatment. Treated and control wines showed colour differences that were visible to human eye, although they were reduced over time. At the end of the study, treated wines showed colour parameters corresponding to younger wines than those observed in control wines. A greater resistance against SO2 bleaching was also observed in treated wines, which can be mainly associated to the greater percentages of polymeric pigments caused by seed treatment and to the improvement of the colloidal stability of SO2-resistant pigments caused by the addition of the MP.


Assuntos
Fermentação , Flavonoides/análise , Manipulação de Alimentos/métodos , Glicoproteínas de Membrana/administração & dosagem , Sementes/química , Vinho/análise , Antocianinas/análise , Cor , Frutas/química , Vitis/química
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