Effect of the chitosan second layer on the gelation and controlled digestion of Citrem-chitosan bilayer emulsions

Research progress on chitin/chitosan-based emulsion delivery systems and their application in lipid digestion regulation

Excessive lipid intake is linked to an elevated risk of health problems. However, reducing lipid contents may influence food structure and flavor. Some alternatives are needed to control the lipid absorption. Emulsions are common carriers for lipids, which can control the hydrolysis and absorption of lipids. Chitin (Ch) and chitosan (CS) are natural polysaccharides with good biodegradability, biocompatibility, and unique cationic properties. They have been reported to be able to delay lipolysis, which can be regarded as one of the most promising agents that regulates lipid digestion (LiD). The application of Ch/CS and their derivatives in emulsions are summarized in this review with a focus on their performances and mechanisms for LiD regulation, aiming to provide theoretical guidance for the development of novel Ch/CS emulsions, and the regulation of LiD. A reasonable design of emulsion interface can provide its resistance to the external environment and then control LiD. The properties of emulsion interface are the key factors affecting LiD. Therefore, systematic study on the relationship between Ch/CS-based emulsion structure and LiD can not only instruct the reasonable design of emulsion interface to accurately regulate LiD, but also provide scientific guidelines for applying Ch/CS in functional food, medicine and other fields.

Pickering Emulsion Stabilized by β-Cyclodextrin and Cinnamaldehyde/β-Cyclodextrin Composite

A Pickering emulsion was prepared using β-cyclodextrin (β-CD) and a cinnamaldehyde (CA)/β-CD composite as emulsifiers and corn oil, camellia oil, lard oil, and fish oil as oil phases. It was confirmed that Pickering emulsions prepared with β-CD and CA/β-CD had good storage stability. The rheological experiments showed that all emulsions had G' values higher than G″, thus confirming their gel properties. The results of temperature scanning rheology experiments revealed that the Pickering emulsion prepared with β-CD and CA/β-CD composites had high stability, in the range of 20-65 °C. The chewing properties of Pickering emulsions prepared by β-CD and corn oil, camellia oil, lard, and herring oil were 8.02 ± 0.24 N, 7.94 ± 0.16 N, 36.41 ± 1.25 N, and 5.17 ± 0.13 N, respectively. The chewing properties of Pickering emulsions made with the CA/β-CD composite and corn oil, camellia oil, lard, and herring oil were 2.51 ± 0.05 N, 2.56 ± 0.05 N, 22.67 ± 1.70 N, 3.83 ± 0.29 N, respectively. The texture properties confirmed that the CA/β-CD-composite-stabilized-emulsion had superior palatability. After 28 days at 50 °C, malondialdehyde (MDA) was detected in the emulsion. Compared with the β-CD and CA + β-CD emulsion, the CA/β-CD composite emulsion had the lowest content of MDA (182.23 ± 8.93 nmol/kg). The in vitro digestion results showed that the free fatty acid (FFA) release rates of the CA/β-CD composite emulsion (87.49 ± 3.40%) were higher than those of the β-CD emulsion (74.32 ± 2.11%). This strategy provides ideas for expanding the application range of emulsifier particles and developing food-grade Pickering emulsions with antioxidant capacity.

Improving the gastrointestinal activity of probiotics through encapsulation within biphasic gel water-in-oil emulsions

The development of probiotics encapsulation strategies has always been a hot topic due to the high sensitivity of probiotics to processing, storage and the gastrointestinal environment. In this study, water in oil (W/O) emulsions of single-phase or dual-phase gels were constructed through the water phase, oil phase alone or all gels. And the W/O emulsions were used to encapsulate Bifidobacterium lactis V9. The effects of water, oil and biphasic gels on the physicochemical properties of the emulsion and the probiotic activity were investigated. Water, oil and biphasic gels contribute to the stability of emulsions. Oil-phase gels make the emulsion form a solid-like texture, while water-phase gels have no significant effect on the liquidity of the emulsion. The microscopic image shows that the probiotics were completely encapsulated in the internal aqueous phase due to the excellent water affinity of probiotic powder. In addition, all W/O emulsions retain higher probiotic activity, which is attributed to good physical isolation during the gastric phase, while oil-phase and biphasic gel emulsions have high probiotic activity after intestinal digestion due to reduced lipid digestion by oil-phase gels. A liquid or solid-state encapsulated probiotic emulsion has been developed and can be used as a coating sauce, solid fat, etc., which can provide additional ideas for probiotic encapsulation systems and functional food development.