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Tri-frequency ultrasound (TFU) at 20-40-60 kHz was used to systematically examine the effects on the multi-scale network structure of an emulsion gel containing orange essential oil prepared with glycosylated whey protein (WP). Treatment intervals of pre-and-post 10, 20, and 30 min were utilized to evaluate the influence and interactions on functional (particle size, zeta-potential), rheological (storage modulus (G′) and loss modulus (G″), and oxidative stability (conjugated diene and peroxide value). The optimized tri-frequency pre- and post-treated sample demonstrated enhanced physical stability as compared to the un-treated sample, as evidenced by droplet size, (from 468.14 ± 0.56 to 214.21 ± 0.42 nm), ζ-Potential (mV) (from −29.67 ± 0.31 to −39.98 ± 1.42), and structural morphology. Structure analysis using FTIR that the aforementioned improvements were made possible through TFU enhanced hydrogen bonds, molecular arrangements with greater order, and improved intermolecular compatibility. XRD results showed gradual shift from 8.32° to 8.64° and from 19.2° to 19.5°, respectively. TFU post-treatment gels exhibited higher viscosity, more pronounced pseudoplastic behavior compare to pre-treatment, attributed to strong interaction forces and three-dimensional gel network. Our results provide valuable insights into the application of multi-frequency ultrasound as a promising technique for designing protein emulsion gels tailored for nutrient delivery systems. [Display omitted] • Tri-frequency ultrasound (TFU) was used to form glycosylated whey protein emulsion gels. • Emulsion gels were prepared without the addition of cross-linking or gelling agents. • TFU avoid protein self-aggregation, thereby enhance emulsion stability. • Pre-and-post treated emulsion gel had a denser and more uniform gel-like structure than un-treated. [ABSTRACT FROM AUTHOR]

Pectins are a diverse family of biopolymers with an anionic polysaccharide backbone of α-1,4-linked d -galacturonic acids in common. They have been widely used as emulsifiers, gelling agents, glazing agents, stabilizers, and/or thickeners in food, pharmaceutical, personal care and polymer products. Commercial pectin is classified as high methoxy pectin (HMP) with a degree of methylation (DM) >50% and low methoxy pectin (LMP) with a DM <50%. Amidated low methoxy pectins (ALMP) can be obtained through aminolysis of HMP. Gelation of HMP occurs by cross-linking through hydrogen bonds and hydrophobic forces between the methyl groups, assisted by a high co-solute concentration and low pH. In contrast, gelation of LMP occurs by the formation of ionic linkages via calcium bridges between two carboxyl groups from two different chains in close proximity, known as the ‘egg-box’ model. Pectin gels exhibit Newtonian behaviour at low shear rates and shear-thinning behaviour when the shear rate is increased. An overview of pectin from its origin to its physicochemical properties is presented in this review. [ABSTRACT FROM AUTHOR]

For the development of innovative foods and nutritional fortification, research into food gel is essential. As two types of rich natural gel material, both legume proteins and polysaccharides have high nutritional value and excellent application potential, attracting wide attention worldwide. Research has focused on combining legume proteins with polysaccharides to form hybrid hydrogels as their combinations show improved texture and water retention compared to single legume protein or single polysaccharide gels, and these properties can be tailored for specific applications. This article reviews hydrogels of common legume proteins and discusses heat induction, pH induction, salt ion induction, and enzyme-induced assembly of legume protein/polysaccharide mixtures. The applications of these hydrogels in fat replacement, satiety enhancement, and delivery of bioactive ingredients are discussed. Challenges for future work are also highlighted. [Display omitted] • Legume protein/polysaccharide hybrid gels show improved texture and water retention. • Gelling properties of legume protein/polysaccharides discussed. • Applications include fat replacement, satiety enhancement, and bioactives delivery. [ABSTRACT FROM AUTHOR]

Chitosan macro- and micro/nano-gels have gained increasing attention in recent years, especially in the biomedical field, given the well-documented low toxicity, degradability, and non-immunogenicity of this unique biopolymer. In this review we aim at recapitulating the recent gelling concepts for developing chitosan-based physical gels. Specifically, we describe how nowadays it is relatively simple to prepare networks endowed with different sizes and shapes simply by exploiting physical interactions, namely (i) hydrophobic effects and hydrogen bonds—mostly governed by chitosan chemical composition—and (ii) electrostatic interactions, mainly ensured by physical/chemical chitosan features, such as the degree of acetylation and molecular weight, and external parameters, such as pH and ionic strength. Particular emphasis is dedicated to potential applications of this set of materials, especially in tissue engineering and drug delivery sectors. Lastly, we report on chitosan derivatives and their ability to form gels. Additionally, we discuss the recent findings on a lactose-modified chitosan named Chitlac, which has proved to form attractive gels both at the macro- and at the nano-scale.

Research on the preparation by in-situ modification of antifouling membranes has grown exponentially. Yet, little is known on their formation mechanisms and dedicated studies could help at improving the fine control of their structure. Our purpose here was to investigate the formation of PVDF/F127 membranes (PEG-type PVDF membranes). F127 was blended with PVDF and vapor-induced phase separation process applied to form the membranes. Like for virgin PVDF membranes, morphology of PVDF/F127 membranes is dependent on the dissolution temperature of the casting solution. The thermodynamic and kinetic effects of copolymer were investigated through the establishment of phase diagram and diffusion kinetics of non-solvent during phase separation. In the conditions tested, solutions containing PVDF and F127 are less viscous than those only containing PVDF. Also, as F127 enhances the chemical affinity of the blend with water, it eventually promotes non-solvent diffusion. Additionally, it reduces the stability of the system. However, despite a major role of copolymer on thermodynamic and kinetic of phase separation, crystallization (size of nodules, nature of polymorphs) is unaffected by F127. The morphology and arising bulk properties of low-biofouling PVDF/F127 membranes is only dependent on the initial nucleation density of crystals prior to phase separation, controlled by the dissolving temperature. [ABSTRACT FROM AUTHOR]

Chitosan macro- and micro/nano-gels have gained increasing attention in recent years, especially in the biomedical field, given the well-documented low toxicity, degradability, and non-immunogenicity of this unique biopolymer. In this review we aim at recapitulating the recent gelling concepts for developing chitosan-based physical gels. Specifically, we describe how nowadays it is relatively simple to prepare networks endowed with different sizes and shapes simply by exploiting physical interactions, namely (i) hydrophobic effects and hydrogen bonds-mostly governed by chitosan chemical composition-and (ii) electrostatic interactions, mainly ensured by physical/chemical chitosan features, such as the degree of acetylation and molecular weight, and external parameters, such as pH and ionic strength. Particular emphasis is dedicated to potential applications of this set of materials, especially in tissue engineering and drug delivery sectors. Lastly, we report on chitosan derivatives and their ability to form gels. Additionally, we discuss the recent findings on a lactose-modified chitosan named Chitlac, which has proved to form attractive gels both at the macro- and at the nano-scale.