Enzyme-assisted aqueous extraction combined with experimental designs allow the obtaining of a high-quality and yield pecan nut oil

Abstract

Enzyme-assisted aqueous extraction (EAE) is an alternative and sustainable process for obtaining edible oil that avoids unfavorable changes in compounds sensitive to high temperatures and extreme pH. In this study, pecan nut oil was obtained by EAE and mechanical pressing (MP), and its physicochemical properties and chemical composition were compared. The extraction conditions were selected applying the enzymes Alcalase® and/or Celluclast® used either singly or in combination. After using the Plackett-Burman design followed by a Central Composite Rotatable Design, the highest extraction yield (65.3%) was obtained using Alcalase® (1.50 g/100 g) after 4 h, in pH 8.00, at 52 °C, and substrate concentration of 0.40 g/mL. The peroxide values (1.99 and 1.90 mEq O2/kg of oil obtained by EAE and MP, respectively), acid values (0.13 g oleic acid/kg) and oxidative stability index (12 h) showed high quality for the oils in both extraction methods used. The samples obtained by EAE and MP showed high concentrations of oleic acid (72–73 g/100 g) and γ-tocopherol (25–27 mg/100 g). The results obtained are the first data in the literature reporting the obtaining of pecan nut oil of high quality and yield using the EAE.