The correlation of wall material composition with flow characteristics and encapsulation behavior of fish oil emulsion

Prosopis alba exudate gum as excipient for improving fish oil stability in alginate-chitosan beads

The aim of the present work was to employ an exudate gum obtained from a South American wild tree (Prosopis alba), as wall material component to enhance the oxidative stability of fish oil encapsulated in alginate-chitosan beads. For this purpose, beads were vacuum-dried and stored under controlled conditions. Oxidation products, fatty acid profiles and lipid health indices were measured during storage. Alginate-chitosan interactions and the effect of gum were manifested in the FT-IR spectra. The inclusion of the gum in the gelation media allowed decreasing the oxidative damage during storage in comparison to the free oil and alginate-chitosan beads. The gum also improved wall material properties, providing higher oil retention during the drying step and subsequent storage. Fatty acids quality and lipid health indices were widely preserved in beads containing the gum. Present results showed a positive influence of the gum on oil encapsulation and stability, being the main mechanism attributed to a physical barrier effect.

Influence of Different Wall Materials on the Microencapsulation of Virgin Coconut Oil by Spray Drying

The main objective of this study was to evaluate the influence of the different wall material combinations on the microencapsulation of virgin coconut oil (VCO) by spray drying. Maltodextrin (MD) and sodium caseinate (SC) were used as the basic wall materials and mixed with gum Arabic (GA), whey protein concentrate (WPC) and gelatin (G). The stability, viscosity and droplet size of the feed emulsions were measured. MD:SC showed the best encapsulation efficiency (80.51%) and oxidative stability while MD:SC:GA presented the lowest encapsulation efficiency (62.93%) but better oxidative stability than the other two combinations. Microcapsules produced were sphere in shape with no apparent fissures and cracks, low moisture content (2.35–2.85%) and high bulk density (0.23–0.29 g/cm3). All the particles showed relatively low peroxide value (0.34–0.82 meq peroxide/kg of oil) and good oxidative stability during storage. MD:SC:GA microencapsulated VCO had the highest antioxidant activity in both of the 2,2-diphenyl-1-picrylhydrazyl (DPPH) (0.22 mmol butylated hydroxyanisole (BHA)/kg of oil) and 2,2-azinobis (3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) assays (1.35 mmol trolox/kg of oil).