Resumo A variabilidade da composição físico-química e do teor de carotenoides e polifenóis, e a capacidade antioxidante hidrofílica da fruta fresca da pupunha (Bactris gasipaes) foram pesquisadas, a fim de avaliar o seu aproveitamento como uma fonte potencial de compostos bioativos. Estudou-se a variabilidade de cinco lotes de frutos da Costa Rica das regiões Tucurrique (T) e Pérez Zeledón (PZ). Foram encontradas diferenças significativas para a massa, o comprimento e a largura entre os lotes. Os teores de umidade, gordura e proteína dos frutos de Tucurrique foram significativamente menores do que os teores dos frutos de Pérez Zeledón. Não foi encontrada diferença significativa para o teor de amido entre todos os lotes de pupunheira estudados. Para os compostos antioxidantes, o teor de carotenoides totais variou entre 109 e 202 mg equivalentes β-caroteno / g de matéria seca (ms), enquanto o teor de polifenóis totais variou no intervalo de 54 a 106 mg de equivalentes de ácido gálico (GAE) / 100 g (ms). Ambos os compostos antioxidantes apresentaram variabilidade entre os cinco lotes. A capacidade antioxidante foi determinada pelo método ORAC e só a amostra PZ-3 foi significativamente diferente dos outros quatro lotes. A média da capacidade antioxidante hidrofílica foi de 37 ± 7 mmol de equivalentes de Trolox (TE) / g (ms). No geral, a fruta da pupunha apresenta potencial de utilização como ingrediente no desenvolvimento de alimentos funcionais, uma vez que a variabilidade da fruta da pupunha como matéria-prima, determinada pela aplicação de uma análise de componente principal, demonstrou que algumas das características dessa fruta não foram afetadas durante a época de colheita, e nenhuma diferença foi encontrada entre os lotes das duas áreas de estudo.

Summary The variability of the physicochemical composition, carotenoid and polyphenol contents and hydrophilic antioxidant capacity of fresh peach palm (Bactris gasipaes) fruit was studied with a view to its exploitation as a potential source of bioactive compounds. The variability present in five batches of peach palm fruit obtained from two regions in Costa Rica: Tucurrique (T) and Pérez Zeledón (PZ), was studied. Significant differences were found for fruit weight, length and width amongst the batches studied. The moisture, fat and protein contents of the Tucurrique fruit were significantly lower than those from Pérez Zeledón. No significant difference in starch content was found between any of the batches of peach palm fruit studied. In terms of antioxidant compounds, the total carotenoid content ranged between 109 and 202 µg β-carotene equivalents/g dry weight (dw), while the total polyphenol content varied from 54 to 106 mg gallic acid equivalents (GAE) /100 g (dw). Both these components presented variability amongst the five batches. The antioxidant capacity was determined by the ORAC method and only the PZ 3 sample presented significant differences from the other four batches. The average hydrophilic antioxidant capacity was 37 ± 7 µmol of Trolox equivalents (TE)/g (dw). Overall, the peach palm fruit showed potential to be used in the development of functional foods since the variability of the raw peach-palm fruit, determined by applying a principal component analysis, showed that some characteristics of this fruit were not affected by harvest time and showed no differences between the batches from the two areas.

Phytochemicals are highly concentrated in berries, especially polyphenols as anthocyanins and ellagitannins. These compounds have been associated with antioxidant capacity, lipid peroxidation protection, anti-inflammatory activity, anti-carcinogenic activity, obesity prevention and others. Blackberries are commonly grown and consumed as juice in Latin-American countries. However, blackberry juice is easily fermented and different industrial techniques are being applied to enable the juice to be stored for longer periods. One important issue required for these techniques is to preserve the health-promoting capacities of blackberries. This study compared the antioxidant activity and the lipid peroxidation protector effect between a fresh blackberry juice (FJ) and a microfiltrated blackberry juice (MJ). Chemical analysis of both juices show less polyphenols concentration in the MJ. Despite this difference, values for biological activities, such as protection of lipid peroxidation, was not significantly different between FJ and MJ. These results suggest that the compounds responsible for the antioxidant activity are maintained even after microfiltration and the free radical scavenging capacity of these compounds could protect the initiation of lipid peroxidation. Microfiltration could be used as an industrial technique to produce blackberry juice that maintains biological activities of polyphenols.