ANTIOXIDANT CAPACITY OF PEQUI (Caryocar brasiliense Camb.) PULP IS PRESERVED BY FREEZE-DRYING AND LIGHT-RESISTANT PACKAGING

Abstract

ABSTRACT Pequi (Caryocar brasiliense Camb.) pulp is rich in bioactive compounds. However, seasonality and perishability limit its availability in the market. This work aimed to determine the physicochemical characteristics, including phenolic compounds and carotenoid concentrations, as well as the antioxidant capacity of lyophilized pequi pulp during storage in various packaging materials for 180 days. Pequi fruits were pulped, ground, freeze-dried and then vacuum packaged in transparent polyethylene (TP), polyethylene coated by aluminum foil (PA) and laminated foil (LA), respectively. The samples were stored under controlled temperature, humidity and luminosity. Proximate composition, phenolic compounds and carotenoids concentrations, and antioxidant capacity (DPPH• assay) were determined at the beginning of the study and the end of each month, during 180 days. Lyophilized pequi pulp had 48.87, 6.17, and 4.20 g.100 g-1 lipids, proteins, and total dietary fiber, respectively, and 556.79 kcal.100 g-1 energy. PA and LA had similar effects against light-induced carotenoid oxidation. Negative correlations between the phenolic compound concentration and storage period, and antioxidant capacity and storage period; and a positive correlation between antioxidant capacity and phenolic compound content were observed. Light-resistant packaging decreased the carotenoid loss. Among the packaging, LA preserved the phenolic compounds and antioxidant capacity most effectively.