Ácidos orgânicos, açúcares, álcoois, compostos fenólicos, propriedades de cor, pH e acidez titulável foram monitorados durante fermentação comercial de jabuticaba (Myrciaria cauliflora) através da espectroscopia de ressonância magnética nuclear (NMR) de 1 H, ensaios espectrofotométricos e métodos usuais de análise. Os dados coletados foram analisados por meio de análise de componentes principais (PCA), agrupamentos (HCA) e correlação canônica (CCA). Dois grupos de amostras foram reconhecidos, e as variáveis responsáveis pela separação foram açúcares, antocianinas, álcoois, tonalidade e ácidos acéticos e succínico. A análise de correlação canônica confirmou a influência dos álcoois (etanol, metanol e glicerol), ácidos orgânicos (ácidos cítrico, acético e succínico), pH e acidez titulável na extração e estabilidade das antocianinas e copigmentos. Consequentemente, as propriedades de cor também foram afetadas pelas variações nos níveis de compostos fenólicos durante o processo de fermentação.Organic acids, sugars, alcohols, phenolic compounds, color properties, pH and titratable acidity were monitored during the commercial fermentation of jabuticaba (Myrciaria cauliflora) by 1 H nuclear magnetic resonance (NMR) spectroscopy, spectrophotometric assays and standard methods of analysis. Data collected was analyzed by principal component (PCA), hierarchical cluster (HCA) and canonical correlation (CCA) analyses. Two sample groups were distinguished and the variables responsible for separation were sugars, anthocyanins, alcohols, hue and acetic and succinic acids. The canonical correlation analysis confirmed the influence of alcohols (ethanol, methanol and glycerol), organic acids (citric, succinic and acetic acids), pH and titratable acidity on the extraction and stability of anthocyanins and copigments. As a result, color properties were also affected by phenolic variation throughout the fermentative process.Keywords: jabuticaba, phenolic compounds, sugars, organic acids, NMR, chemometrics Introduction Jabuticaba (Myrciaria cauliflora Berg.) is a Brazilian fruit that bears an edible purplish-black sweet fruit. It has a slightly acid taste and is rich in phenolic compounds, such as anthocyanins, flavonoids, tannins and depsides, which are responsible for antioxidant and anti-inflammatory activities, as well as for colon cancer cell cytotoxicity. 1 High sugar content of jabuticaba makes it suitable for jam, juice, liqueur and wine production. 2 Wines made from jabuticaba have shown great acceptance in sensory analysis and a higher antioxidant activity than grape wines in a β-carotene/linoleic acid system. 3,4 Several fruit wines have been made from Brazilian tropical fruits such as cashew, 5 cacao, gabiroba, umbu and cupuaçu. 3 Such industrial processing is an alternative to prevent post-harvesting losses and to promote exotic fruit production, allowing a more rational use of Cerrado and Amazonian biomes (Brazil). Like most beverages, fruit wines not only have to be in accordance with the current legislation but also ac...

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Eugenia unifl ora L., Myrtaceae, leaves contain high amounts of phenolic compounds which are responsible for several pharmacological activities. In order to evaluate the phenolics seasonal variation leaves were analysed on a monthly basis during the period of two years for the contents of hydrolysable tannins, total phenols, fl avonoids, and nutrients (N, P, K, S, Ca, Mg, Mn, Zn, Cu, and Fe). Results were correlated with climate conditions (rainfall, humidity, and mean temperature) by Principal Component and Cluster Analysis which allowed four groups to be distinguished with respect to the age of the leaves and the content of some metals. Young leaves were characterised by high levels of Zn and nitrogen whereas old leaves contained high levels of Fe and calcium, and both groups had moderate amounts of phenolics. Adult leaves were divided in two groups and results revealed that while one group had the highest levels of all phenols and lowest amounts of Mn and Cu, the other showed opposite quantities. The Canonical Correlation Analysis confi rmed a highly signifi cant negative correlation between phenol contents and Mn and Cu. These facts suggested that fl avonoids and tannins production depends of the amounts of foliar nutrients, Cu and Mn in particular, which are cofactors of enzymes involved in phenol degradation and lignin biosynthesis. This knowledge can improve this specie cultivation in order to enhance the phenolic compounds concentration.

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The chemical composition of the essential oil, phenolic contents, and foliar nutrients of Eucalyptus microcorys leaves, cultivated in Brazil, was analysed on a monthly basis for one year. Canonical redundancy analysis correlated results with climate conditions (rainfall, humidity, and mean temperature), allowing three groups to be distinguished as regards temperature, flavonoids, and the content of some metals. Strong correlations between Mn, Cu, Zn, Ca, P, and K with some monoterpenes and phenolic compounds were observed. Oxygenated monoterpenes were predominant in all sampling months. Oil chemovariation may be influenced by climatic factors as well as by foliar nutrient variation.

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