Brazilian peach production is insufficient for domestic supply. Aiming to increase production in the state of Minas Gerais, 16 new peach tree varieties were introduced in the Serra da Mantiqueira region and their fruit were analyzed for sugar, total phenol and total carotenoid contents by colorimetric methods, and for organic acid content by high-performance liquid chromatography. In addition, we examined the effect of fruit bagging on the levels of such constituents. To do so, the fruit of half the trees of each variety were bagged. The levels of sugars, phenols, carotenoids and organic acids are genotypic characteristics and significantly differed among varieties. Despite being a good form of fruit protection, providing better aspect and reducing the need for pesticides, bagging leads to lower contents of components such as sugars, phenols and organic acids in most varieties. However, it cannot be stated that this practice interferes with sensory characteristics. Knowledge of the chemical constituents of these new varieties allows determining those ideal for fresh consumption (e.g., "Maciel", "Diamante", "T. Beauty", "Ouromel 2" and "C.1056", among others) and those more suitable for industrial processing (e.g., "A. Gold", "C.1122" and "C.1050"), as well as those which serve both purposes.

Diferentes solventes foram avaliados para a extração de pigmentos antociânicos da jabuticaba, identificação, quantificação e verificação da estabilidade das antocianinas, assim como a condução de três testes de atividade antioxidante e determinação dos níveis de vitamina C. A maceração com etanol acidificado com HCl 1.5 mol L-1 (85:15) promoveu melhor extração e estabilidade dos pigmentos. As cascas são ricas em pigmentos antociânicos, apresentando 1,59 e 2,06 g 100 g-1 de matéria seca (MS) nas variedades Paulista e Sabará, respectivamente. Cyanidina 3-glucosideo é o pigmento majoritário nas cascas, seguido pela delphinidina 3-glucosideo. Os níveis de vitamina C foram mais altos nas cascas e sementes de ambas as variedades. Foi verificado que as cascas apresentaram maior atividade antioxidante, tanto na captura de radical livre, quanto no retardo do processo de oxidação lipídica.

Different solvents were evaluated for the extraction of jabuticaba anthocyanin pigments, identifying, quantifying and verifying the stability of the anthocyanins, as well as the conduction of three antioxidant activity assays and determination of the vitamin C levels. The maceration with ethanol acidified with HCl 1.5 mol L-1 (85:15) provides better pigment extraction and stability. The skin is anthocyanin rich, presenting 1.59 and 2.06 g 100 g-1 of dry matter in the Paulista and Sabará varieties, respectively. Cyanidin 3-glucoside is the majority pigment of the skins, followed by delphinidin 3-glucoside. The highest level of vitamin C was found in the skins and seeds of both varieties. It was verified that the skins, presented more antioxidant activity, in free radical capture, as well as in retarding the lipid oxidation process.

O objetivo deste trabalho foi determinar a composição dos açúcares, ácidos orgânicos e minerais do fruto inteiro e frações (casca, polpa e semente) dos genótipos de jabuticabeira Paulista (Plinia cauliflora) e Sabará (P. jaboticaba), assim como a composição do óleo das cascas e sementes. As frutas apresentaram elevados teores de açúcares totais, destacando-se a frutose, seguida de glicose e sacarose. No genótipo Paulista, foram encontrados teores mais elevados de açúcares totais e redutores na polpa e na casca, o que não foi observado ao comparar os frutos inteiros dos dois genótipos. Foram encontrados cinco ácidos orgânicos na seguinte ordem quantitativa: ácido cítrico > ácido succínico > ácido málico > ácido oxálico > ácido acético. Potássio foi o mineral mais abundante encontrado. A fruta mostrou também ser rica em magnésio, fósforo, cálcio e cobre. O óleo das sementes mostrou ter praticamente a mesma constituição do óleo extraído das cascas, e os compostos majoritários foram um fitosterol não identificado, os ácidos palmítico, linoleico e oleico e o esqualeno.

The aim of this work was to determine the sugar, organic acid and mineral compositions of the whole fruit and fractions (skin, pulp and seed) of the Paulista (Plinia cauliflora) and Sabará (Plinia jaboticaba) jabuticaba tree genotypes, as well as the oil compositions of their skin and seeds. High levels of sugar, especially fructose, followed by glucose and sucrose, were encountered in the fruit. In the Paulista genotype, higher levels of total and reducing sugars were found in the pulp and skin, which was not observed when comparing the whole fruit of both genotypes. Five organic acids were found in the whole fruit and in the fractions of the two jabuticaba genotypes in quantitative order: citric acid > succinic acid > malic acid > oxalic acid > acetic acid. Potassium was the most abundant mineral found. This fruit was also shown to be rich in magnesium, phosphorus, calcium and copper. The seed oil had nearly the same constitution as the oil extracted from the skin in both genotypes and the major compounds were an unidentified phytosterol, palmitic, linoleic and oleic acids, and squalene.