EFFECTS OF TEMPERATURE AND SOLVENT CONCENTRATION ON THE PRESSURIZED LIQUID EXTRACTION OF PEQUI (Caryocar brasiliense Camb.) PEEL

Pequi (Caryocar brasiliense Camb.) is a Brazilian savanna fruit composed of 76% peel, 13% core, 9% pulp and 2% almond. Its processing and commercialization are basically artisanal. The pulp is the most used part, so the other parts of the fruit are often discarded. One of them, the peel, is rich in fiber and bioactive compounds such as polyphenols and carotenoids. Pressurized liquid extraction (PLE) is a technique that uses solvents at high pressure and temperature to extract bioactive compounds with a significant efficiency compared to other extraction methods. The use of mixtures of ethanol and water as a solvent in PLE results in shorter extraction times and greater global yields. Therefore, this work aimed to assess the global yield of PLE using mixtures of ethanol and water as solvents at different temperatures and concentrations of ethanol, and to determine the best extraction condition for pequi peel. PLE was performed using around 3 grams of pequi peel at 10 "±" 0.5 MPa, temperatures of 60, 85 and 110 °C and mixtures of ethanol in water at 50, 75 and 100% (v/v) with mass flow rate of approximately 5 g/min. The extracts were compared regarding global yield ("X" _"0" ). There was a variation from 17.12 to 45.30% of "X" _"0" . The best PLE conditions were: 110 °C at 50, 75 and 100% EtOH (v/v), 85 °C at 100% EtOH (v/v) and 60 °C at 75 and 100 % EtOH (v/v). The improvement in global yield with increasing temperature was not so evident, since the greatest yield was obtained at all temperatures. Regarding the solvent, 100% EtOH (v/v) achieved the best result at all temperatures. Thus, PLE seems to be a faster and more sustainable extraction technique compared to other conventional methods.