Optimization of the extraction process of polyphenols from cashew apple agro-industrial residues

The goal of this study was to determine the chemical composition of cashew apples agro-industrial residue and optimize the process of polyphenols extraction in this residue. The extraction process conditions were defined using a 24-1 fractional factorial experimental design using acetone and methanol as solvents. The independent variables were: time (30 to 90 min), temperature (30 to 50 °C), solvent concentrations (50% to 90%), agitation speed (100 to 300 rpm); the dependent variables were: total phenolic content and DPPH scavenging capacity. The optimized process was carried out by applying the Central Composite Rotational Design (CCRD) considering the results obtained with the 24-1 fractional factorial experimental design. The residue presented bioactive compounds in its composition, with emphasis on the content of total phenolic compounds (1975.64 mg/ 100 g). The extraction process was not affected by methanol; however, acetone affected the amounts of extracted phytochemicals. Extracts with high levels of polyphenols and strong DPPH scavenging capacity (> 80%) were obtained using 55% acetone, 30 minutes, 30 °C, and 150 rpm. The results showed that cashew apple residue is a potential natural source of bioactive compounds with strong antioxidant capacity. These compounds could be used partially or totally to replace synthetic antioxidants.

Chemical and volatile composition of jujube wines fermented by Saccharomyces cerevisiae with and without pulp contact and protease treatment

Abstract This study evaluated the chemical and volatile composition of jujube wines fermented with Saccharomyces cerevisiae A1.25 with and without pulp contact and protease treatment during fermentation. Yeast cell population, total reducing sugar and methanol contents had significant differences between nonextracted and extracted wine. The nonextracted wines had significantly higher concentrations of ethyl 9-hexadecenoate, ethyl palmitate and ethyl oleate than the extracted wines. Pulp contact also could enhance phenylethyl alcohol, furfuryl alcohol, ethyl palmitat and ethyl oleate. Furthermore, protease treatment can accelerate the release of fusel oils. The first principal component separated the wine from the extracted juice without protease from other samples based on the higher concentrations of medium-chain fatty acids and medium-chain ethyl esters. Sensory evaluation showed pulp contact and protease could improve the intensity and complexity of wine aroma due to the increase of the assimilable nitrogen.