Application of Tamarind Waste Extracts to Improve the Antioxidant Properties of Tamarind Nectars.

Tamarind fruits are consumed worldwide and their seeds have an underexploited potential. We assessed the effect of the addition of a freeze-dried aqueous of extract tamarind seed (FAE) at three concentration levels (0.3, 1.15 and 2%) on the antioxidant capacity (DPPH, ABTS, FRAP and ORAC) and concentrations of total phenolic compounds in tamarind pulp. Conditions used to prepare the aqueous extracts were established using multivariate optimization. Moreover, nectars prepared from pulps combined with FAE were subjected to sensory tests. Tamarind fruits from three geographic regions in Brazil (Minas Gerais, São Paulo and Bahia) that were harvested in 2013 and 2014 were used in the study. Generally, the freeze-dried aqueous extracts increased the concentrations of antioxidants in the pulp. The results revealed a positive correlation between the FAE concentration in the pulp and the antioxidant capacity of all samples, particularly samples from Bahia and Minas Gerais, which presented an increase of up to 1,942% in the ABTS method when 2% FAE was incorporated into the pulp, from approximately 40.1 to 209.1 mMTrolox/gdw and 13.4 to 143.4 mMTrolox/gdw, respectively. Sensory tests indicated the satisfactory acceptance and non-distinction between nectar samples to which FAE was or was not added when the FAE concentration was less than 2.3gFAE/L, regardless of the geographic origin of the samples.

A comprehensive characterization of Solanum lycocarpum St. Hill and Solanum oocarpum Sendtn: Chemical composition and antioxidant properties.

In this study we evaluated the proximate composition of two Solanaceae fruits from Brazilian Cerrado, their mineral content, volatile organic compounds (VOCs), phenolic compounds profile, and antioxidant capacity employing Oxygen Radical Absorbance Capacity (ORAC) assay, for each part of the fruits (pulp, peel and seeds). Our results showed that the pulp has a high moisture content (74.62-85.40 g/100 g) and soluble fiber (1.29-2.06 g/100 g) content, and low fat, protein, and ash content. The peel exhibited high levels of carbohydrates and total fibers (6.55-11.39 and 12.35-13.12 g/100 g, respectively), while the seed presented high content of fat, protein, and insoluble fiber (10.14-12.62, 9.14-13.24 and 19.84-23.15 g/100 g). Potassium is the main mineral found in both fruits. It is the first time that the carbohydrate profile, volatile components, and phenolic compounds of the fruta-do-lobo and juá-açu are reported. 1-Kestose (GF2) and nystose (GF3) were found in both fruits. The main VOCs of juá-açu were esters, while in fruta-do-lobo, aldehydes were the major components. UPLC-Q-ToF fraction analysis of juá-açu and fruta-do-lobo revealed 24 phenolic compounds, most being hydroxycinnamic acids derivatives in juá-açu, and chlorogenic acids in fruta-do-lobo. The antioxidant capacity (ORAC) of the fruits ranged from 1.35 to 11.51 µmol TE/100 mL of extract. These results indicate that Solanum genus can be interesting for the Brazilian fruit market, and that it has potential to be exploited for agroindustry for diversification of fruit products.