Pea Protein Isolates: Novel Wall Materials for Microencapsulating Flaxseed Oil

This study investigated the potential of three commercially available pea protein isolates (PPIs), Nutralys (Roquette, USA), PP (Znaturals, USA), and Pulseplus80 (AGT, Canada) as wall materials for microencapsulating flaxseed oil. Microencapsulation with spray drying was conducted with PPIs at 10 % concentration and varied flaxseed-oil-to-wall-material ratios (1:5, 1:3.3, and 1:2.5). All three PPIs emulsion prepared using 1:5 core-to-wall ratio were stable. Microencapsulation efficiencies (MEs) at 1:5 core-to-wall-material ratio were 90.46, 84.9, and 71.9 % for Nutralys, PP, and Pulseplus80, respectively. Results show that when the core-to-wall-material ratio increased to 1:2.5, the MEs decreased to 67.9, 75.6, and 44.6 % for Nutralys, PP, and Pulseplus80, respectively. Proximate composition of PPIs influenced the functional properties and emulsion stability and, ultimately, MEs. Electrophoresis and Fourier transform infrared spectroscopy (FTIR) analyses were conducted to determine differences in these three proteins. This study also evaluated microcapsules prepared with 1:5 ratio for water content, water activity, solubility, and morphological properties. Findings demonstrate that PPI, a natural, low-cost, allergen-free ingredient can be used effectively as a wall material for microencapsulation at a 10 % solid concentration.