Barley β-glucan aerogels as a carrier for flax oil via supercritical CO2

Flax oil has important implications in human health, however, it must be protected in food systems to maintain bioactivity and avoid rancidity. Impregnation of active compounds in polymer networks using supercritical CO2 (SCCO2) has shown potential for their protection and delivery. Aerogels were formed with barley beta-glucan using SCCO2 drying. Impregnation of flax oil in barley beta-glucan aerogels using SCCO2 was evaluated when oil was added at different stages of the drying process (before, during and after drying) and under static and dynamic processes at different processing times (2,6 and 8 h), temperatures (40 and 60 degrees C) and pressures (15 and 30 MPa). Impregnated aerogels were analyzed using Fourier-transform infrared spectrometry and scanning electron microscopy. Addition of oil during the drying process and the use of a dynamic flow regime resulted in the highest loading of aerogels. Oil loading increased with processing time, from 47.79% (lipid as % of total impregnated aerogel mass) after 4 h to 60.96% after 8 h, and with increasing pressure. Aerogel impregnation using SCCO2 has potential as a delivery vehicle for high-value food grade compounds, including flax oil. (C) 2012 Elsevier Ltd. All rights reserved.