A Mild Method for Encapsulation of Citral in Monodispersed Alginate Microcapsules

Area of Science:

• Materials Science
• Chemical Engineering
• Biotechnology

Background:

• Citral is sensitive to UV light and acid, limiting its application.
• Existing encapsulation methods often involve harsh conditions unsuitable for sensitive compounds.

Purpose of the Study:

• To develop a mild and effective method for encapsulating citral in calcium alginate microcapsules.
• To ensure the stability and controlled release of citral for various applications.

Main Methods:

• Utilized a microfluidic device to create monodispersed oil-in-water-in-oil (O/W/O) emulsions.
• Incorporated sodium alginate, a calcium-ethylenediaminetetraacetic acid (EDTA-Ca) complex, and D-(+)-Gluconic acid δ-lactone (GDL) in the emulsion's middle phase.
• Triggered alginate cross-linking via GDL hydrolysis, releasing calcium ions under mild pH conditions.

Main Results:

• Successfully prepared uniform, monodispersed calcium alginate microcapsules containing citral.
• Optimized preparation conditions, including constituent concentrations and GDL mixing.
• Demonstrated sustained release of citral and its efficacy in delaying oil oxidation.

Conclusions:

• The developed mild gelling method effectively encapsulates acid- and UV-sensitive hydrophobic actives like citral.
• This technique offers potential applications in the pharmaceutical, food, and cosmetic industries.
• The microcapsules provide sustained release and protection for sensitive ingredients.