Preparation, characterization, formation mechanism and stability of allicin-loaded emulsion gel

The processing instability and strong pungent smell limit the use of allicin. To overcome these shortcomings, emulsion gels loaded with allicin were constructed using soybean protein isolate (SPI) and gum Arabic (GA) through ultrasound treatment and transglutaminase (TG) induction. The effect of ultrasonic modification and GA concentration on the physical properties of emulsion gels was investigated, and the protective effect of emulsion gel on allicin was evaluated. The results showed that ultrasonic pretreatment of SPI can significantly improve the water holding capacity, hardness, viscosity, and elasticity modulus of emulsion gels, forming denser homogeneous network structure, and these properties were best when GA concentration was 0.3%. In the process of gel formation, ultrasound can change the spatial structure of protein, the introduction of polysaccharide can enhance the hydrogen bond between molecules, and TG can promote the intramolecular crosslinking, the three worked together to form a gel network. The encapsulation efficiency of the ultrasonic SPI-GA emulsion gel can reach 70.84%, while it was only 26.63% for the SPI emulsion gel. The degradation of allicin was inhibited under strong light and high temperature. This study provides a new idea for the development of functional food rich in allicin.