ABSTRACT: Double pruning extended the harvest season of wine grape (Vitis vinifera L.) to dry winter, enabling production of high quality wines in the southeastern Brazil. Winter harvest allows grapes to fulfill not only technological maturation, but also phenolic ripeness. Winter wines from Syrah grapes harvested from eight vineyards in southeastern Brazil during three harvests were analyzed for their chemical and aromatic composition after bottling and after ageing for 20, 30, and 42 months in bottle. Winter wines have high content of total phenolic compounds, which remained almost constant through ageing, as well as color intensity. Malvidin 3-O-glucoside stood out among anthocyanins, remaining 5-10 % after 39 months of ageing. Moreover, malvidin 3-O-glucoside-pyruvic acid was the main pyranoanthocyanin identified in winter wine. Polymerized pigments index ranged from 54 % at bottling to 80 % after 42 months of ageing. Young winter wines are rich in ester and monoterpene, as well as alcoholic volatile compounds responsible for ethereal, fruity, flowery, fresh and sweet aromas. Aged winter wines showed higher contents of furfural, geranyl ethyl ether, isoamyl decanoate, α-muurolene and α-calacorene, contributing to sweet, fruity and woody aromas. Syrah winter wines are characterized by high content of phenolic compounds and color stability, and keep good sensorial characteristics after ageing in bottle.

Abstract This exploratory work aims to identify the potential inhibitors of lactic bacterial growth and to propose enological practices to guarantee the occurrence of spontaneous malolactic fermentation (MLF) in wines from traditional and double-pruning management harvests in southeast Brazil. One white wine from a summer harvest and one red wine from a winter harvest that failed to complete MLF were utilized as comparative models to identify inhibitor compounds to lactic bacteria. Wine composition, alcoholic-fermentation temperature and bacterial strain contribute to the success or failure of MLF. Temperatures below 12 °C during alcoholic fermentation decrease lactic bacterial metabolism and may impair the bacteria’s growth after yeast cells lysis. A must pH below 3.2 in a summer harvest impairs bacterial growth, and the association of low pH with a free-SO2 concentration above 10 mg L-1 may inhibit MLF. For grapes with a high sugar content, harvested in the winter cycle, enologists should keep the alcohol content below 15% and control the alcoholic-fermentation temperature.

Abstract Brazilian Savannah native fruits have been investigated as potential sources of antioxidant substances. Cagaita, cerrado cashew and gabiroba were characterized with regard to the ascorbic acid and phenolic contents, antioxidant capacity and flavonoids composition. Gabiroba presented higher contents of ascorbic acid (61.5 mg.100 g–1), total phenolic compounds (1,222.59 mg GAE.100 g–1), and antioxidant capacity (DPPH, FRAP and ORAC assays) than cagaita and cerrado cashew. The correlation coefficients between total ascorbic acid or total phenolic contents and antioxidant capacity were strong and significant (0.970 ≤ r ≤ 0.998). Quercetin derivatives were found in cagaita (1.94 mg.100 g–1) and myricetin derivatives in cerrado cashew (1.2 mg.100 g–1). Peonidin 3-glucoside was the main anthocyanin in cerrado cashew, and its flavonoids composition was first identified in this study. Gabiroba showed relevant catechin content (23.32 mg.100 g–1). These Brazilian native fruits may be considered as important sources of bioactive compounds, notably gabiroba, since it presents high phenolic contents and antioxidant capacity.

Cinco cultivares de amora-preta (Rubus sp.) foram avaliadas quanto a sua capacidade antioxidante, perfil de compostos bioativos e composição físico-química. Os níveis de ácido ascórbico total, presentes na forma de ácido desidroascórbico, variaram entre 9,8 a 21,4 mg.100 g-1 (b.u.). Os principais flavonóides presentes nas cinco cultivares foram: a antocianina cianidina (66 a 80% do total de flavonóides); o flavan-3-ol epicatequina; e os flavonóis quercetina e traços de caenferol. As cinco cultivares apresentaram alta capacidade antioxidante quando avaliadas pelo sistema de co-oxidação β-caroteno/ácido linoléico, similar ao antioxidante sintético BHT, na concentração de 50 µM. A cultivar Guarani apresentou os maiores teores de flavonóides totais, antocianina total, cianidina e de capacidade antioxidante, enquanto que a cultivar Caigangue apresentou alto conteúdo de vitamina C e de fenólicos totais. Estas duas cultivares também apresentaram uma boa correlação TSS/TA. Assim, a amora-preta pode ser considerada uma boa fonte de compostos bioativos e assim contribuir com a manutenção do estado de saúde.

Five blackberry cultivars (Rubus sp.) were evaluated for antioxidant capacity, bioactive compounds and composition. Ascorbic acid levels, consisting of dehydro-ascorbic acid, ranged from 9.8 to 21.4 mg.100 g-1 fresh weight. Cyanidin (66 to 80% of total flavonoids), epicatechin, quercetin and traces of kaempferol were the main flavonoids found in all cultivars. The five cultivars presented high antioxidant capacity in the β-carotene/linoleic acid system, with inhibition similar to the synthetic antioxidant BHT, at a 50 µM concentration. Caingangue cultivar presented high vitamin C and total phenolics content, while Guarani had the highest cyanidin, total anthocyanin and total flavonoids levels and also the highest antioxidant capacity. These cultivars also presented good TSS/TA ratios. From the data, at a quantitative level, blackberry can be considered a good source of bioactive compounds, as well as potentially beneficial to human health.

O objetivo deste estudo foi determinar a capacidade antioxidante, o teor e as formas de isoflavonas presentes nos produtos derivados de soja e compará-los à soja em grão. A capacidade antioxidante foi mensurada por meio do método de cooxidação do beta-caroteno/ácido linoléico e pelo seqüestro de radicais livres (DPPH•). Os resultados mostraram que o conteúdo de isoflavonas nos produtos variou de 95 a 711 mg/100 g (b.s.) e o teor de fenólicos totais de 101 a 413 mg equivalentes de catequina/100 g (b.s.), sendo que o grão de soja apresentou um conteúdo de 110 e 200 mg/100 g (b.s.), respectivamente, para isoflavonas e fenólicos totais. Em relação às formas de isoflavonas a farinha integral e sua respectiva farinha desengordurada e a farinha desengordurada de soja comercial apresentaram predominância de conjugados malonilglicosídeos ebeta-glicosídeos, similar aos grãos de soja. O suplemento à base de gérmen de soja e a farinha desengordurada de soja apresentaram a maior capacidade antioxidante por ambos os métodos (5 µmoles equivalentes de trolox/g e ~ 0,8 µmoles equivalentes de BHT/ g amostra b.s.). Os resultados demonstraram que o conteúdo total e tipo de isoflavonas e o teor de fenólicos dos produtos de soja dependem do processamento e que a capacidade antioxidante desses produtos varia significativamente.

The objective of this study was to determine the antioxidant activity and isoflavone content and type of soy seeds and soy products. The antioxidant activity was measured using beta-carotene bleaching and 2.2-diphenyl-1-picryl-hydrazyl (DPPH•) free radical methods. The total isoflavone content of soy products varied from 95 to 711 mg/100 g DW (expressed as aglycones) and total phenolics content from 101 to 413 mg equivalents of catechin/100 g DW. Soybeans presented 110 and 200 mg/100 g DW of isoflavones and total phenolics, respectively. The beta-glycosides and malonylglycosides were the main forms of the isoflavones found in the whole flour, defatted flour and commercial defatted flour, similar to the soy seeds. The soy germ (hypocotyl) and the defatted soy flours presented the highest antioxidant activities in both methods (5.0 µmoles equivalents of trolox/g DW and ~ 0.8 µmoles equivalents of BHT/g DW). Taking this into account, the results showed that total isoflavone and phenolic contents and isoflavone profile of soy products depend on processing conditions and that antioxidant activity varied significantly among products.