RESUMO

The objective of this work was to validate a method for direct determination in grape juice and wine of 1-kestose, nystose and raffinose oligosaccharides by reversed-phase high-performance liquid chromatography with refractive index detection using a new type of RP-C18 column (150 × 4.6 mm, 4 µm) with polar end-capping. The validated methodology was also used to characterize grape juice and fine wine products from Northeastern Brazil; and presented suitable linearity, precision, recovery, limits of detection and quantification. The method presented good specificity, revealing that sugars, organic acids, and ethanol (the main interferences in refraction detection) did not influence the quantification of the studied oligosaccharides. The main oligosaccharide found was 1-kestose (approximately 50% of the samples), followed by raffinose (20% of the samples). The results obtained in this are an indication that grape juices and wines have the potential to be functional beverages in relation to the presence of prebiotics.

RESUMO

Munguba (Pachira aquatica Aubl) is an oleaginous seed native of southern Mexico and northern Brazil,and it is cultivated as gardening ornament. For investigating its use as food or as an ingredient in foodmanufacturing, the centesimal composition, protein fractions and some anti-nutricional factors werecharacterized. The lipid and protein contents were of 46.62% and 13.75%, respectively, which characterizeit as being an oleaginous species. In a pie form, the protein contents was of 28.27. The following essentialamino acids (g/100 g of protein) were found: valine (7.16), leucine (7.97) and lysine (5.27), but a limitedamount of methionine + cysteine (2.42). Among the non-essential amino acids, aspartic acid (12.70) andglutamic acid (17.11g) showed the highest indices. For protein classification the globulin fraction was inhighest index (56.24%), followed by albumin (22.86%), glutelins (14.22%) and prolamins (1.45%), beingconsistent with the characteristic profile of plant storage proteins. Four protein subunits ranging from 97.4KDa to 29.0 KDa were found by electrophoretic analysis. The tanine contents was of 6.34 mg/g, and thehaemagglutination activity was detected. The munguba seeds demonstrated the nutritional characteristicswhich are suitable for being used in food manufacturing and aquiculture.

A munguba (Pachira aquatica Aubl) é uma semente oleaginosa nativa do Sul do México e Norte do Brasil,cultivada como espécie ornamental. Com o propósito de investigar o seu uso na alimentação ou comoingrediente na indústria alimentícia, foram avaliados a composição centesimal, a fração proteica e algunsfatores antinutricionais. A taxa de lipídeos foi de 46,62% e a proteica foi de 13,75%, com características típicasde espécie oleaginosa. Na forma de torta, o índice proteico foi de 28,27%. Foram detectados os aminoácidosessenciais (g/100 g de proteína): valina (7,16), leucina (7,97) e lisina (5,27), porém, valor limitante demetionina + cisteína (2,42). Quanto aos aminoácidos não essenciais, os maiores índices foram de ácidoaspártico (12,70) e ácido glutâmico (17,11). Na classificação proteica, a fração globulínica apresentou índicede 56,24%, albumina (22,86%), glutelinas (14,22%) e prolamina (1,43%). Pela análise eletroforética foramobservadas quatro subunidades proteicas variando de 97,4 KDa a 29 KDa. O teor de tanino foi de 6,34mg/g e a presença de atividade hemaglutinante foi detectada. A semente de munguba possui característicasproteicas adequadas, que possibilita o seu uso na indústria alimentícia e na aquicultura.