Encapsulation of Flaxseed Oil Using a Benchtop Spray Dryer for Legume Protein-Maltodextrin Microcapsule Preparation

Flaxseed oil was microencapsulated employing a wall material matrix of either chickpea (CPI) or lentil protein isolate (LPI) and maltodextrin using a benchtop spray dryer. Effects of emulsion formulation (oil, protein and maltodextrin levels) and protein source (CPI vs LPI) on the physicochemical characteristics, oxidative stability, and release properties of the resulting capsules were investigated. Microcapsule formulations containing higher oil levels (20% oil, 20% protein, 60% maltodextrin) were found to have higher surface oil and lower encapsulation efficiencies. Overall, LPI maltodextrin capsules gave higher flaxseed oil encapsulation efficiencies (similar to 88.0%) relative to CPI maltodextrin matrices (similar to 86.3%). However, both designs were found to provide encapsulated flaxseed oil protection against oxidation over a 25 d room temperature storage study relative to free oil. Overall, similar to 37.6% of encapsulated flaxseed oil was released after 2 h under simulated gastric fluid, followed by the release of an additional similar to 46.6% over a 3 h period under simulated intestinal fluid conditions.