Optimization of Fish Oil Spray Drying Using a Protein:Inulin System

Abstract

The aim of this work was to investigate the use of an unconven-tional polymeric material, inulin, in fish oil spray drying. The influence of inlet air temperature, oil load, and carrier substitution (whey protein isolate by inulin) on the physical properties of particles containing fish oil was investigated. Increasing the oil load caused an increase in the surface oil; however, the presence of inulin favorably decreased the particle surface oil when a high oil lad was applied. The parameters hygroscopicity and wettability were also influenced by the inulin fraction. The higher inlet air temperature produced larger particles with lower densities. The best operating conditions were determined to be an air temperature of 185°C, a 40% inulin fraction, and a 6% oil load. The results indicate that inulin is an alternative carrier in the fish oil spray-drying process.

Keywords:

• Encapsulation
• Fructan
• Omega-3
• Response surface methodology
• Spray drying
• Whey protein

Notes

1-inlet air temperature; 2-inulin fraction; 3-oil load in relation to emulsion.

ns: not significant (p >0.10).

**Significant at 5% probability.

*Significant at 10% probability.

X_eq: equilibrium moisture content (g·g ⁻¹ dry powder); X_m: monolayer moisture content (g·g ⁻¹ dry powder); C, K: model constants related to monolayer and monolayer properties; aw: water activity; a, b: model parameters; E: mean relative deviation modulus; R ²: coefficient of determination.