Release properties of gel-type W/O/W encapsulation system prepared using enzymatically-modified starch

Area of Science:

• Materials Science
• Food Science
• Chemical Engineering

Background:

• Developing stable encapsulation systems is crucial for controlled release applications.
• Water-in-oil-in-water (W/O/W) emulsions offer potential for encapsulating active ingredients.
• Thermoreversible gels can provide tunable release profiles based on temperature.

Purpose of the Study:

• To develop and characterize a novel gel-based encapsulation system using 4-α-glucanotransferase (4αGTase) treated starch and W/O/W emulsions.
• To investigate the influence of preparation conditions and temperature on the physical and release characteristics of the W/O/W gels.
• To evaluate the role of 4αGTase-treated starch in enhancing emulsion stability and controlling release.

Main Methods:

• Preparation of W/O/W emulsions with varying sonication times and W/O volume fractions.
• Incorporation of W/O/W emulsions into a thermoreversible gel matrix using 4αGTase-treated starch.
• Investigation of emulsion stability, encapsulation efficiency (EE), and dye release kinetics.
• Assessment of gel properties and dye release at temperatures ranging from room temperature to 90 °C.

Main Results:

• Sonication time affected encapsulation efficiency and dye release rate; longer sonication improved stability but increased fast release.
• Dye release rate showed a slight increase with temperature for gels with higher W/O volume fractions.
• Gels with lower W/O volume fractions exhibited higher dye release rates and a more significant increase at 90 °C.
• 4αGTase-treated starch significantly improved W/O/W emulsion stability, retarding dye release even at elevated temperatures.

Conclusions:

• The developed gel-based encapsulation system using 4αGTase-treated starch and W/O/W emulsions offers tunable physical and release characteristics.
• 4αGTase-treated starch plays a key role in enhancing emulsion stability, leading to improved control over dye release, particularly at higher temperatures.
• The findings suggest potential applications for this system in areas requiring controlled release of encapsulated substances under varying thermal conditions.