ABSTRACT
The antioxidant activity and bioactive compounds of different blackberry fruit genotypes from the major Brazilian producer region (three cultivars and four selections) were evaluated and compared to the Cherokee cultivar. Phenolic and anthocyanic extracts were obtained and evaluated for each fruit genotype. The phenolic extracts of selections 02/96 and 07/001 presented higher antioxidant activity than those of cultivars in most assays. This activity was partially correlated to the higher amount of total phenolics in these samples. Thus, the phenolic compounds are probably the major responsible for the antioxidant activity in the diphenyl-2-picrylhydrazyl radical scavenging assay (DPPH), ferric reducing antioxidant power (FRAP) assay and thiobarbituric acid reactive substances (TBARS) assay. Quercetin seems to be responsible for the antioxidant activity of blackberry phenolic extracts in the ß-carotene bleaching assay. Concerning anthocyanic extracts, the selection 02/96 and Cherokee cultivar from harvest 2007 had higher antioxidant activity than the other genotypes in most assays. Anthocyanins appear to be the major responsible for the antioxidant activity of anthocyanic extracts in the DPPH and FRAP assays, although ascorbic acid also contributed to the DPPH antioxidant activity. Selection 02/96 appears to have higher antioxidant activity than the commercial cultivars cultivated in the southern Brazil and appears to be promising for nutritional and health purposes.
Subject(s)
Ascorbic Acid , Polyphenols , Rubus , Anthocyanins , Antioxidants , FruitABSTRACT
A amora-preta (Rubus sp.) é uma fruta cuja exploração comercial está iniciando no Brasil. Seu cultivo iniciou na década de 70 e vem aumentando com a introdução e adaptação de novas cultivares. Porém, pouco se conhece sobre as disparidades geradas na composição e nas características das frutas dessas novas plantas. O objetivo deste trabalho foi avaliar as características físico-químicas de diferentes cultivares ('Tupy', 'Guarani' e 'Cherokee') e seleções (02/96, 07/001 e 03/001) de amora, que estão sendo estudadas para originar cultivares adaptadas à região Sul do Brasil. Foram analisados a cor objetiva, sólidos solúveis (SS), pH, acidez titulável, composição centesimal e ácidos graxos de amoras. As frutas apresentaram umidade entre 84,8 e 90,3%; proteína entre 0,09 e 0,14%, fibra alimentar entre 5,8 e 5,5% e cinzas entre 0,27 e 0,49%. A seleção 02/96 apresentou menor teor de cinzas. Os SS variaram entre 7,3 a 10,2°Brix, a acidez titulável variou entre 1,30 e 1,58% em ácido cítrico e o pH entre 2,8 e 3,1. A seleção 03/001 apresentou menor valor de SS que as demais e menor tendência ao vermelho, mas maior intensidade de cor que a cultivar 'Tupy'. Os ácidos graxos encontrados em maior concentração foram o ácido palmítico (22-29%), oléico (13-32%) e linoléico (15-33%), com diferenças nas concentrações entre os tipos de amora. As variedades de amora-preta avaliadas apresentaram bom valor nutricional com níveis de açúcar e acidez adequados para a industrialização, além de conter ácidos graxos importantes para a manutenção da saúde.
Blackberry (Rubus sp.) is a fruit whose commercial exploitation is starting in Brazil. Its cultivation began in the 70's and is increasing with the introduction and adaptation of new cultivars. However, little is known about the disparities in the composition and characteristics of the fruit from these new plants. The objective of this study was to evaluate the physicochemical characteristics of different cultivars ('Tupy', 'Guarani' and 'Cherokee') and selections (02/96, 07/001 and 03/001) of blackberries, which are being studied to generate cultivars adapted to Southern Region of Brazil. The objective color, soluble solids (SS), pH, titratable acidity, proximate composition and fatty acids of blackberries were evaluated. The fruit humidity ranged between 84.8 and 90.3%; protein between 0.09 and 0.14%, dietary fiber between 5.5 and 5.8% and ash between 0.27 and 0.49%. Selection 02/96 had the lowest ash content. SS ranged from 7.3 to 10.2°Brix, titratable acidity ranged between 1.30 and 1.58% citric acid and pH between 2.8 and 3.1. Selection 03/001 had the lowest SS value and it also had lower redness, but higher color saturation than 'Tupy' cultivar. The fatty acids found at higher concentration were palmitic (22-29%), oleic (13-32%) and linoleic acid (15-33%), with differences in the concentration among blackberry genotypes. The varieties of blackberry evaluated showed good nutritional value with sugar and acidity levels suitable for industrialization. It also contained fatty acids important for maintaining health.