Solid phase microextraction as a reliable alternative to conventional extraction techniques to evaluate the pattern of hydrolytically released components in Vitis vinifera L. grapes

In present research, headspace solid-phase microextraction (HS-SPME) followed by gas chromatography–mass spectrometry (GC–qMS), was evaluated as a reliable and improved alternative to the commonly used liquid–liquid extraction (LLE) technique for the establishment of the pattern of hydrolytically released components of 7 Vitis vinifera L. grape varieties, commonly used to produce the world-famous Madeira wine. Since there is no data available on their glycosidic fractions, at a first step, two hydrolyse procedures, acid and enzymatic, were carried out using Boal grapes as matrix. Several parameters susceptible of influencing the hydrolytic process were studied. The best results, expressed as GC peak area, number of identified components and reproducibility, were obtained using ProZym M with b-glucosidase activity at 35 °C for 42 h. For the extraction of hydrolytically released components, HS-SPME technique was evaluated as a reliable and improved alternative to the conventional extraction technique, LLE (ethyl acetate). HS-SPME using DVB/CAR/PDMS as coating fiber displayed an extraction capacity two fold higher than LLE (ethyl acetate). The hydrolyzed fraction was mainly characterized by the occurrence of aliphatic and aromatic alcohols, followed by acids, esters, carbonyl compounds, terpenoids, and volatile phenols. Concerning to terpenoids its contribution to the total hydrolyzed fraction is highest for Malvasia Cândida (23%) and Malvasia Roxa (13%), and their presence according previous studies, even at low concentration, is important from a sensorial point of view (can impart floral notes to the wines), due to their low odor threshold (μg/L). According to the obtained data by principal component analysis (PCA), the sensorial properties of Madeira wines produced by Malvasia Cândida and Malvasia Roxa could be improved by hydrolysis procedure, since their hydrolyzed fraction is mainly characterized by terpenoids (e.g. linalool, geraniol) which are responsible for floral notes. Bual and Sercial grapes are characterized by aromatic alcohols (e.g. benzyl alcohol, 2-phenylethyl alcohol), so an improvement in sensorial characteristics (citrus, sweet and floral odors) of the corresponding wines, as result of hydrolytic process, is expected.

Characterization of volatile substances in apples from rosaceae family by headspace solid‐phase microextraction followed by GC‐qMS

The volatile composition of different apple varieties of Malus domestica Borkh. species from different geographic regions at Madeira Islands, namely Ponta do Pargo (PP), Porto Santo (PS), and Santo da Serra (SS) was established by headspace solid-phase microextraction (HS-SPME) procedure followed by GC-MS (GC-qMS) analysis. Significant parameters affecting sorption process such as fiber coating, extraction temperature,extractiontime,sampleamount,dilutionfactor,ionicstrength,anddesorption time,wereoptimizedanddiscussed.TheSPMEfibercoatedwith50/30 lmdivinylbenzene/carboxen/PDMS (DVB/CAR/PDMS) afforded highest extraction efficiency of volatile compounds, providing the best sensitivity for the target volatiles, particularly whenthesampleswereextractedat508Cfor30 minwithconstantmagneticstirring. A qualitative and semi-quantitative analysis between the investigated apple species has been established. It was possible to identify about 100 of volatile compounds amongpulp(46,45,and39),peel(64,60,and64),andentirefruit(65,43,and50)inPP, PS,andSSapples,respectively.Ethylesters,terpenes,andhigheralcoholswerefound tobethemostrepresentativevolatiles. a-Farnesene,hexan-1-olandhexyl2-methylbutyratewerethecompoundsfoundinthevolatileprofileofstudiedappleswiththelargestGCarea,representing,onaverage,24.71,14.06,and10.80%ofthetotalvolatilefractionfromPP,PS,andSSapples.InPPentireapple,themostabundantcompoundsidentified were a-farnesene (30.49%), the unknown compound m/z (69, 101, 157) (21.82%) andhexylacetate(6.57%).RegardingPSentireapplethemajorcompoundswere a-farnesene(16.87%),estragole(15.43%),hexan-1-ol(10.94),andE-2-hexenal(10.67).a-Farnesene(30.3%),hexan-1-ol(18.90%),2-methylbutanoicacid(4.7%),andpentan-1-ol(4.6%) werealsofoundasSSentireapplevolatilespresentinahigherrelativecontent.Principal component analysis (PCA) of the results clustered the apples into three groups according to geographic origin. Linear discriminant analysis (LDA) was performed in order to detect the volatile compounds able to differentiate the three kinds of apples investigated. The most important contributions to the differentiation of the PP, PS, and SS apples were ethyl hexanoate, hexyl 2-methylbutyrate, E,E-2,4-heptadienal, pethylstyrene,andE-2-hexenal.

Modos de vida de jovens na Madeira

Os modos de vida dos jovens da Madeira refletem a forma de sentir, pensar e agir dos jovens no quadro dos contextos sociais que marcam as condições da sua existência e os seus espaços de atuação. Atender à atualização do conhecimento sobre o modo como os jovens integram os estímulos que recebem e os traduzem em expressões de vida, impõe uma sempre renovada produção científica que permita formulações e reformulações teóricas para a compreensão das dinâmicas sociais que determinam ajustamentos e reajustamentos nos modos de vida dos jovens. Compreender como se estruturam esses modos de vida a partir dos contextos socioeconómicos e culturais juvenis, permitindo a elaboração de um quadro tipológico de modos de vida de jovens madeirenses, constituiu o objetivo deste estudo. Interessa-nos principalmente compreender o que marca a vida dos jovens madeirenses no séc. XXI em contextos de mudança e os atuais condicionamentos e fronteiras do processo de transição para a vida adulta. Tendo em conta o corpo de conhecimento contemporâneo da sociologia da juventude, da sociologia das classes sociais e dos seus instrumentos metodológicos de pesquisa, foi possível identificar os principais indicadores de trajetória e condição de vida dos atores, permitindo, a partir da análise dos dados obtidos, desenhar um quadro de cinco tipos de modos de vida dos jovens na Madeira.

El desarrollo social en los años noventa: principales opciones

Incluye Bibliografía

Desarrollo, crisis y equidad en América Latina

Incluye Bibliografía

Equidad, transformación social y democracia en América Latina

Expone el principal desafío de la democracia en América Latina, que es el de la transformación social con equidad y justicia.

Los dilemas de la equidad social en la Argentina finisecular

Incluye Bibliografía

Colombia: su desarrollo social y opciones para los años noventa

Analiza las causas, los orígenes, la política actual y la opción para los años noventa de la desigualdad y de los problemas sociales en Colombia.

Una perspectiva del desarrollo social en Brasil

Incluye Bibliografía

Subdesarrollo sin equidad y sin desarrollo: la experiencia de Guatemala

Incluye Bibliografía

Las políticas sociales en Costa Rica

Incluye Bibliografía

Hacia la utopía: tenemos que ser menos desiguales

Incluye Bibliografía

Participación y concertación en las políticas sociales

Señala la incompatibilidad de un desarrollo social sustentado en la baja del producto e infiere la necesidad de reconsiderar las relaciones entre políticas económicas y sociales, y la consiguiente división del trabajo entre las funciones estatales.

Envejecimiento, solidaridad y protección social en América Latina y el Caribe: La hora de avanzar hacia la igualdad

Incluye Bibliografía

Ageing, solidarity and social protection in Latin America and the Caribbean: time for progress towards equality

Includes bibliography