Optimization of the Encapsulation of Lemuru Fish Protein Hydrolysate by Spray-Drying Using Response Surface Methodology.

Abstract

Research background: Encapsulating lemuru fish protein hydrolysate is important to maintain its stability. However, optimal conditions for the encapsulation process of lemuru fish protein hydrolysate using statistical methods remain unexplored. This study aims to address this problem by optimizing the encapsulation conditions.

Experimental approach: Maltodextrin and gum Arabic were used as carrier agents, with mass per volume ratio ranging from 10 to 30 %, and spray dryer inlet temperatures between 90 and 100 °C. In this study, we analysed the main interactions of these variables using response surface methodology (RSM).

Results and conclusions: Our results show that mass per volume ratio of maltodextrin of 25 % and inlet temperature of 100 °C are the optimal conditions for the encapsulation of fish protein hydrolysate. The optimal conditions resulted in a high desirability index of 0.864, indicating an effective balance between yield, solubility and hygroscopicity. The actual results also fall well within the confidence interval of the predicted values, confirming the robustness of the model and the reliability of the predicted optimal encapsulation conditions. Encapsulated fish protein hydrolysate was compared with its non-encapsulated counterpart and characterised using Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), and particle size analyser (PSA) to validate the results. The encapsulated fish protein hydrolysate showed distinct properties, such as the presence of functional groups from maltodextrin, interconnected particle and more homogeneous and narrower particle size distribution.

Novelty and scientific contribution: The encapsulation of lemuru fish protein hydrolysate using maltodextrin with mass per volume ratio of 25 % and inlet temperature 100 °C was successful in improving the properties of the protein hydrolysate. Further research should explore the functional properties of fish protein hydrolysate.