EFFECT OF COOKING ON THE NUTRITIONAL PROPERTIES, BIOACTIVE COMPOUNDS AND ANTIOXIDANT CAPACITY OF ORANGE AND YELLOW PEELS OF PEACH PALM FRUITS (Bactris gasipaes)

Peach palm fruits (Bactris gasipaes) are native to the Amazonia and present interesting chemical composition for food design practices, mainly related to the bioactive compounds, which may provide functional claiming to them. The consumption of peach palm fruit occurs after cooking with salty water and its peel may be considered a by-product with high technological potential due to the presence of high contents of bioactive compounds, specifically carotenoids. Thus, the effect of cooking on the proximate composition, phenolic compounds, and carotenoid composition (HPLC-DAD) were investigated for the peach palm peels of fruits from the orange and yellow peel-colored varieties. Moreover, the scavenging capacity against ABTS●+ was also evaluated. Regarding the proximate composition, in general, slightly differences were observed for all the parameters in the raw and cooked peels for both varieties, being total lipids the one with noticed increase variation after cooking (13-37%). The cooked peels decreased by ≈15% in relation to the phenolic compounds (105 to 89 mg GAE/100 g) for the orange peel; however an opposite effect was observed for total carotenoids with an increase of ≈13% (62 to 72 mg/100 g). None variation regarding the total phenolic compounds or carotenoids was observed for the yellow variety after cooking. The carotenoid profile confirmed the presence of 14 and 7 known carotenoids of peach palm from orange and yellow varieties, respectively, being (all-E)-β-carotene the major compounds in both raw and cooked orange peel samples (20-23%), while (all-E)-lutein was the major in the yellow peels (42-44%). Furthermore, the presence of Z-isomers of β-Carotene showed a slightly increase after cooking, as expected. Concerning the antioxidant potential, the extract of orange peels were able to scavenge ABTS●+ before and after cooking (IC50= 292 µg/mL and 494 µg/mL, respectively), while the yellow variety did not show activity up the highest tested concentration (666 µg/mL). Therefore, traditional consumption of peach palm fruits after cooking generates peels with high technological potential to be used as high-added by-product as functional alternative ingredients for the food industry application.