Hydrogel-based encapsulation strategy for nobiletin stabilization

Controlling bioactive components' crystal growth, especially for hydrophobic functional factors, is an effective pathway for achieving their stabilization. Here, our paper proposes a method utilizing hydrogel to regulate crystal growth, using nobiletin (NOB) as a model. Results showed that the NOB crystallization was controlled by gellan gum (GG) concentrations and the ratios of GG to NaCl. Notably, 1% of GG-based hydrogel with 0.5% NaCl efficiently inhibited the crystals' growth. X-ray diffraction results confirmed that GG could regulate the crystallinity of NOB. Fourier transform infrared spectroscopy analysis verified the presence of hydrogen bond interaction between GG and NOB. Besides, the texture and rheological properties of GG-NOB composite gels were also investigated in detail. More importantly, the final composite gels exhibited sustained release properties and significantly improved release efficiency compared to the pure NOB sample. In summary, our study proposed a straightforward stabilization strategy for hydrophobic substances, attempting to overcome some of the barriers in food processing and storage.