Encapsulation and delivery of bioactive citrus pomace polyphenols: a review

Abstract

Citrus pomace consists of the peel, pulp, and membrane tissues remaining after juice expression. Globally, around one million tons of citrus pomace are generated annually, which contains a variety of bioactive constituents that could be used as value-added functional ingredients in foods. However, the polyphenols in citrus pomace are not currently being utilized to their full potential, even though they can be used as nutraceuticals in functional foods and beverages. Citrus phenolics face significant roadblocks to their successful incorporation into these products. In particular, they have poor water solubility, chemical stability, and bioavailability. This review describes the diverse range of colloidal systems that have been developed to encapsulate and deliver citrus phenolics. Examples of the application of these systems for the encapsulation, protection, and delivery of polyphenols from citrus pomace are given. The use of colloidal delivery systems has been shown to improve the stability, dispersibility, and bioaccessibility of encapsulated polyphenols from citrus pomace. The selection of an appropriate delivery system determines the handling, storage, shelf life, encapsulation efficiency, dispersibility, and gastrointestinal fate of the citrus polyphenols. Furthermore, the purity, solubility, and chemical structure of the polyphenols are key factors in delivery system selection.

Recent advances on the stability of dietary polyphenols

“…The interactions between polyphenol and β‐cyclodextrin/protein/polysaccharide via microencapsulation and encapsulation can improve the stability, solubility, safety, bioavailability, biocompatibility, and bioactivity of polyphenols (Figure 6). The microencapsulation of polyphenols with β‐cyclodextrin significantly improves the processing stability and bioaccessibility of mulberry polyphenols (Li et al, 2020), olive pomace polyphenols (Radić et al, 2020), citrus pomace polyphenols (Caballero et al, 2021). Application of polyphenol‐ protein/polysaccharide interaction to fabrication, nanoparticles, emulsion, and encapsulation has been applied to improve the thermal stability and antioxidant activity of EGCG, resveratrol, quercetin, chlorogenic acid, and isoflavone.…”

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

“…16,[19][20][21] Of these studies, none used a plant protein. A more detailed review of existing research and opportunities in citrus pomace polyphenol encapsulation can be found in Caballero et al 22 The objective of this research was to assess the efficacy of a colloidal delivery system assembled from PPI and high methoxyl pectin (HMP) to encapsulate, protect, and deliver HT. Our specific objectives were to optimize the formation of stable PPI-HMP electrostatic complexes, determine the maximum concentration of HT that could be encapsulated within these complexes, and then to assess the impact of encapsulation on the dispersibility, antioxidant activity, and in vitro bioaccessibility of this polyphenol.…”

Microencapsulation of Chokeberry Polyphenols and Volatiles: Application of Alginate and Pectin as Wall Materials

“…Another factor determining the encapsulation of compounds inside alginate beads is their polarity. For more hydrophobic polyphenols, poor encapsulation occurs due to non-incorporation into the encapsulation mixture, which usually consists of hydrophilic materials, such as alginate or pectin, and thus their encapsulation remains a challenge [ 24 ].…”