Microencapsulation of β-carotene using barley residue proteins from beer waste as coating material

Abstract

This study aimed to produce and characterise microparticles produced from barley residue proteins (BRP) enriched with β-carotene. The microparticles were obtained by freeze-drying five emulsion formulations with 0.5% w/w whey protein concentrate and different concentrations of maltodextrin and BRP (0, 1.5, 3.0, 4.5 and 6.0% w/w), with the dispersed phase consisting of corn oil enriched with β-carotene. The mixtures were mechanically mixed and sonicated, the formed emulsions were freeze-drying. The microparticles obtained were tested for encapsulation efficiency, humidity, hygroscopicity, apparent density, scanning electron microscopy (SEM), accelerated stability and bioaccessibility. Microparticles produced with the emulsion containing 6% w/w BRP had lower moisture content (3.47 ± 0.05%), higher encapsulation efficiency (69.11 ± 3.36%), bioaccessibility value of 84.1% and greater β-carotene protection against thermal degradation. SEM analysis showed that microparticles had sizes ranging from 74.4 to 244.8 µm. These results show that BRP are viable for the microencapsulation of bioactive compounds by freeze-drying.

Keywords:

• Freeze-drying
• agro-industrial waste
• provitamin A carotenoid
• β-carotene microparticles
• barley protein
• extraction with natural solvent

Acknowledgements

The authors would also like to thank the Central of Analysis and Chemical Prospecting and the Laboratory of Electronic Microscopy and Ultrastructural Analysis of the Federal University of Lavras, as well as Finep, Fapemig, Capes and CNPq for supplying the equipment and technical support for experiments involving Fourier transform infrared spectroscopy and electron microscopy analyses.

Disclosure statement

No potential conflict of interest was reported by the author(s).

Data availability statement

All data generated or analysed during this study are included in this manuscript.

Additional information

Funding

The authors thank the financial support provided by Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) – Finance Code 001 and Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq), Grant number - 308911/2021-0.