Recent development of egg protein fractions and individual proteins as encapsulant materials for delivery of bioactives.

Egg proteins, as one of the most abundant animal protein sources, have received considerable attention for developing delivery systems. Among all egg proteins, egg white (ovalbumin) is the most promising encapsulant due to its excellent properties such as gelling, digestibility, self-assembly, amphiphilic nature. In this review paper, we focused particularly on egg protein-based delivery systems with superior encapsulation and delivery functions, including polymeric nanoparticles, emulsions, hydrogels and aerogels. Egg protein-based delivery systems across a wide range of geometry and dimensions have been applied to protect or control-release bioactive small molecules and macromolecules, probiotics and metal nanostructures. However, there are challenges that must be carefully addressed for advancing the practical applications of egg protein-based delivery system in foods, including allergenicity from ovalbumin and ovotransferrin, intolerance to environmental conditions, limited processing technologies. More efforts are warranted to fill knowledge gaps related to fabrication, utilization and digestive mechanisms of egg protein-derived delivery systems.

Effect of Cationic Modified Microcrystalline Cellulose on the Emulsifying Properties and Water/Oil Interface Behavior of Soybean Protein Isolate.

Stabilizing emulsion using complex biopolymers is a common strategy. It would be very interesting to characterize the impact of charge density on the emulsifying properties of complex polyelectrolytes carrying opposite charges. In this study, cationic modified microcrystalline celluloses (CMCC) of different charge densities were prepared and mixed with soy protein isolate (SPI) for emulsion applications. CMCC-1 to 3 with various cationic charge values were successfully prepared as characterized by zeta-potential and FTIR. The positive charge density's effects on solubility, thermogravimetric properties, and rheological properties were studied. Complexes of SPI-CMCC with various zeta-potential values were then obtained and used to stabilize soybean oil emulsions. The results show that emulsions stabilized by complexes of SPI and CMCC-3 at a ratio of 1:3 had the best emulsification ability and stability. However, the interfacial tension-reducing ability of complexes decreased continuously with increasing cationic charge value, while the rheological results show that complexes of SPI-CMCC-3 at a ratio of 1:3 formed a stronger viscoelastic network than other complexes. Our results indicate that this SPI-CMCC complex formula showed excellent emulsification performance, which could be adjusted and promoted by changing the charge density. This complex formula is promising for fabrication of emulsion-based food and cosmetic products.

Exploring the role of chitosan in affecting the adhesive, rheological and antimicrobial properties of carboxymethyl cellulose composite hydrogels.

Natural polysaccharide-based hydrogels are promising in food and pharmaceutical applications. In this study, the potential of composite hydrogels prepared by carboxymethyl cellulose (CMC) and chitosan as glue for cigar wrapping applications was firstly studied. The impacts of degree of carboxymethyl substitution (DS) and the ratio of CMC:chitosan on the adhesive performance and rheological behaviors of composite hydrogels have been investigated. And the results indicated that relatively low DS of CMC and relatively low ratio of chitosan might be favorable for the adhesive properties of composite hydrogels. But a higher ratio of chitosan may significantly improve the rheological properties of composite hydrogels and alter their thermal-sensitivity. The impacts of chitosan on the wet ability with tobacco leaf, the morphology and the XRD patterns of composite hydrogels were also observed. The CMC-chitosan composite hydrogel could significantly decrease the total molds on tobacco leaf brought by CMC, and therefore may show great potential to improve the quality of cigar during long-term storage. All the information in this study is new, which could be useful for exploring the application of CMC-chitosan composite hydrogel in food, pharmaceutical, even other fields.