Impact of process and physico-chemical conditions on the formation of curcumin-whey protein composite particles capable to stabilize food-compatible oil in water emulsions

Sustainable Pickering Emulsions with Nanocellulose: Innovations and Challenges

The proper mix of nanocellulose to a dispersion of polar and nonpolar liquids creates emulsions stabilized by finely divided solids (instead of tensoactive chemicals) named Pickering emulsions. These mixtures can be engineered to develop new food products with innovative functions, potentially more eco-friendly characteristics, and reduced risks to consumers. Although cellulose-based Pickering emulsion preparation is an exciting approach to creating new food products, there are many legal, technical, environmental, and economic gaps to be filled through research. The diversity of different types of nanocellulose makes it difficult to perform long-term studies on workers' occupational health, cytotoxicity for consumers, and environmental impacts. This review aims to identify some of these gaps and outline potential topics for future research and cooperation. Pickering emulsion research is still concentrated in a few countries, especially developed and emerging countries, with low levels of participation from Asian and African nations. There is a need for the development of scaling-up technologies to allow for the production of kilograms or liters per hour of products. More research is needed on the sustainability and eco-design of products. Finally, countries must approve a regulatory framework that allows for food products with Pickering emulsions to be put on the market.

Sonophotodynamic inactivation of Pseudomonas aeruginosa biofilm mediated by curcumin

The inactivation of Pseudomonas aeruginosa biofilm is a major challenge, as biofilms are less responsive to conventional treatments and responsible for persistent infections. This has led to the investigation of alternative approaches for biofilm control such as photodynamic (PDI) and sonodynamic (SDI) inactivation. The combination of them, known as Sonophotodynamic Inactivation (SPDI), has improved the effectiveness of the process. Curcumin, a well-established photosensitizer, has been identified as a potential sonosensitizer. This study evaluated the most effective combination for SPDI against P. aeruginosa biofilms in vitro, varying curcumin concentrations and ultrasound intensities. The results indicated that the inactivation was directly proportional to the curcumin concentration. Using curcumin 120 µM and 3.0 W.cm-2 of ultrasound intensity, SPDI demonstrated the highest and the best synergistic results, equivalent to 6.9 ± 2.1 logs of reduction. PDI reduced 0.7 ± 0.9 log and SDI had no effect. In conclusion, SPDI with curcumin is a promising approach for biofilm inactivation.

Effect of Steam Flash-Explosion on Physicochemical Properties and Structure of High-Temperature Denatured Defatted Rice Bran Protein Isolate

The effects of Steam Flash-Explosion (SFE) on the physicochemical properties and molecular structure of high-temperature denatured defatted rice bran protein isolate (RBPI) were investigated. The mechanism of SFE treatment on high-temperature denatured defatted RBPI was revealed. The analysis of the physical and chemical properties of RBPI showed that the surface hydrophobicity, characteristic viscosity, and thermal stability of rice bran protein isolate were significantly affected by the pressure of saturated steam and pressure holding time. Under the conditions of 2.1 MPa and 210 s, the surface hydrophobicity index decreased significantly from 137.5 to 17.5, and the characteristic viscosity increased significantly. The peak temperature of denaturation decreases from 114.2 to 106.7 °C, and the enthalpy of denaturation decreases from 356.3 to 231.4 J/g. The higher structure (circular dichroic spectrum and endogenous fluorescence spectrum) of rice bran protein isolate was analyzed by volume rejection chromatography (SEC). The results showed that steam flash treatment could depolymerize and aggregate RBPI, and the relative molecular weight distribution changed greatly. The decrease in small molecules with poor solubility was accompanied by the increase in macromolecules (>550 kDa) soluble aggregates, which were the products of a Maillard reaction. The contents of free sulfhydryl and disulfide bonds in high-temperature rice bran meal protein isolate were significantly increased, which resulted in the increase in soluble aggregates containing disulfide bonds. Circular dichroism (CD) analysis showed that the α-helix content of the isolated protein was significantly decreased, the random curl content was increased, and the secondary structure of the isolated protein changed from order to disorder. The results of endogenous fluorescence spectroscopy showed that the high-temperature rice bran meal protein isolate was more extended, tryptophan was in a more hydrophilic microenvironment, the fluorescence intensity was reduced, and the tertiary structure was changed. In addition, the mean particle size and net surface charge of protein isolate increased in the aqueous solution, which was conducive to the development of the functional properties of the protein.