Microencapsulation of canola oil by lentil protein isolate-based wall materials

• A lentil protein isolate-maltodextrin-alginate wall entrapped oil.
• Wall material provided protection against oxidation.
• A bi-layer wall material was formed around the oil droplets.

The overall goal was to encapsulate canola oil using a mixture of lentil protein isolate and maltodextrin with/without lecithin and/or sodium alginate by spray drying. Initially, emulsion and microcapsule properties as a function of oil (20%–30%), protein (2%–8%) and maltodextrin concentration (9.5%–18%) were characterized by emulsion stability, droplet size, viscosity, surface oil and entrapment efficiency. Microcapsules with 20% oil, 2% protein and 18% maltodextrin were shown to have the highest entrapment efficiency, and selected for further re-design using different preparation conditions and wall ingredients (lentil protein isolate, maltodextrin, lecithin and/or sodium alginate). The combination of the lentil protein, maltodextrin and sodium alginate represented the best wall material to produce microcapsules with the highest entrapment efficiency (∼88%). The lentil protein-maltodextrin-alginate microcapsules showed better oxidative stability and had a stronger wall structure than the lentil protein-maltodextrin microcapsules.