Encapsulation of oils recovered from olive stones using particles from gas saturated solutions technique

This study explores the use of the Particles from Gas Saturated Solutions (PGSS) technique to encapsulate oils extracted from olive stones, a by-product of olive oil production. The oil, containing high levels of oleic (72.1 ± 2.5 %) and linoleic acid (16.4 ± 1.2 %), was oxidative stable for 34 ± 2 days at 40 °C. To improve this stability, the oil was encapsulated using PGSS technique under various pressures (10 and 20 MPa), oil-to-wall material ratios (1:10 and 3:10), and nozzle sizes (600 and 1000 μm). Best encapsulation conditions were found to be 10 MPa, 1:10 oil-to-wall material ratio, and 600 μm nozzle. These conditions produced microparticles with 70.0 ± 4.2 % encapsulation efficiency and a Carr index of 20.5 ± 1.4 %, improving the oil oxidative stability to 60 days at 40 °C. This enhancement was confirmed through isothermal calorimetry, peroxide value, and malondialdehyde levels. The results showed that PGSS encapsulation method may significantly improve the oil oxidative stability, producing powdered ingredients from by-products suitable for food and cosmetic applications.