Low-cost liquid lipase selective deacidification of corn oil with high triglyceride yield

Abstract

In order to remove free fatty acids (FFA) in crude oil and improve edible oil quality, deacidification was often used in oil refining. In this work, several liquid enzymes were firstly screened for the selective deacidification of the degummed corn oil, and ethanol was used as a novel fatty acyl acceptor in solvent-free system, which showed a good selective deacidification efficiency and high triglyceride yield. Reaction conditions were optimized by response surface methodology as follows: 3 % enzyme dosage and 20:1 substrate ratio (alcohol/FFA) at 50 °C for 50 min. Under these conditions, the acid value, yield of neutral oil, and contents of sterol and vitamin E of corn oil were 0.31 ± 0.06 mgKOH/g, 94.0 ± 0.5 %, 1,012.9 ± 11.2 mg/100 g, and 1,320.0 ± 3.8 mg/kg, respectively. Meanwhile, thermodynamic and kinetic parameters were investigated. These results showed that this process was beneficial to selective deacidification, high yields of neutral oil and bioactive components in corn oil.