Hesperetin (citrus peel flavonoid aglycone) encapsulation using pea protein-high methoxyl pectin electrostatic complexes: complex optimization and biological activity.

Background: Orange pomace polyphenols have potential for use as nutraceutical ingredients in functional foods and beverages. However, owing to their low water solubility and bioaccessibility, they are not being utilized to their full potential. The goal of this research is to assess the impact of encapsulation on hesperetin (HT - a model orange polyphenol) water solubility, antioxidant activity, and in vitro bioaccessibility.

Results: In this study, a citrus flavonoid aglycone, HT, was encapsulated within water-dispersible colloidal complexes (d = 350 ± 8 nm) formed by electrostatic attraction of pea protein isolate and high-methoxyl pectin at a mixing ratio of 1:1 (v/v) and pH 4. The maximum amount of HT that could be dispersed in water was much higher for the encapsulated form (99 ± 7 μg mL ) than the non-encapsulated form (<10 μg mL ). The radical scavenging activity of the encapsulated HT (>90%, pH 4) was much higher than the non-encapsulated form (<15% at pH 4 or 7). The in vitro bioaccessibility of encapsulated HT (27 ± 7%) was also much higher than the non-encapsulated form (<7%).

Conclusion: These results suggest that a well-designed, biopolymer-based delivery system may improve the effective incorporation of HT, and potentially other orange pomace polyphenols, into food and beverage products. This could provide an additional high-value use for orange juicing by-products while introducing a new nutraceutical product to the food and beverage industry. © 2022 Society of Chemical Industry.