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In this study, we investigated the influence of trans -cinnamaldehyde (CIN) and emulsion size on the physicochemical properties and functionality of emulsion gels. Myofibrillar protein or lecithin emulsions were fabricated with different ratios of canola oil and CIN and different emulsion droplet sizes. The emulsion gels showed a significant dependence on CIN concentration in terms of gel strength and rheological properties because of the improved interaction between proteins and aldehydes through the Schiff base reaction. In addition, the physical properties of the micro-sized emulsion gels were better than those of the nano-sized gels. There was no significant difference in the water-holding capacity. According to the scanning electron and confocal microscopy images, the CIN emulsion gels formed a denser microstructure and had a higher homogeneity with higher CIN concentrations. This suggested that CIN promoted protein cross-linking because the monophenol molecule had fewer structural obstacles. The structural properties were analyzed using Fourier-transform infrared spectroscopy. It was also confirmed that lipid oxidation was inhibited by CIN. The information obtained in this study could be used to develop protein-based products with novel functional properties for use in meat products and in other applications. [Display omitted] • Different of droplet size and oil type affected MP emulsion gel properties. • Myofibrillar protein emulsion gel composed to CIN enhanced gel strength and G′ via Schiff base reaction. • CIN affected retarded of oxidation of emulsion gels. • Physical properties of the micro-sized emulsion gels were better than those of the nano-sized ones. [ABSTRACT FROM AUTHOR]

In this study, we aimed to investigate the effects of emulsion droplet size on the physicochemical and rheological properties of emulsion–gelatin composite gels. Gelatin or lecithin solutions (1–4%) as emulsifiers were homogenized with canola oil using a high-speed and/or high-pressure homogenizer to obtain micro- and nano-sized emulsions. Gelatin (8%) was mixed with an equal amount of the prepared emulsion and subsequently cooled at 4 °C for cold-set gelation. Gel strength of the emulsion–gelatin composite gels was higher when the concentration of gelation was increased, regardless of the droplet size of the emulsion. In terms of droplet size, gel strength, G′, and water-holding capacity of emulsion–gelatin composite gels with nano-sized emulsions were significantly higher than those of gels with micro-sized emulsions, except for lecithin. Fourier-transform infrared and differential scanning calorimetry analyses of emulsion–gelatin composite gels revealed that the emulsion size had a significant effect on the physicochemical properties of the gels, except for lecithin. Conformationally, droplet size influenced the gel strength of the emulsion–gelatin composite gels owing to the high specific surface area of the nano-sized droplets, which formed a relatively high number of junctions of gelatin random coils during cold-set gelation. [Display omitted] • The properties of emulsion–gelatin composite gel can be improved by using gelatin to produce small particles. • The highest G′ and WHC values were seen in the 4% gelatin nano-sized emulsion gels. • Using DSC and FT-IR, gel characteristics were structurally validated. [ABSTRACT FROM AUTHOR]

This study investigated the effects of κ-carrageenan (κ-Car) and methyl cellulose (MC) on the characteristics and stability of gelled single and double emulsion (SE and DE). Gelled SE and DE were consisted with κ-Car (0% or 0.5%, w/w) in the external aqueous phase and MC (0% or 3%, w/w) in the oil phase. The homogenizing process involved at 700 rpm for 3 min using propeller homogenizer and then at 15,000 rpm for 5 min using a high-speed homogenizer. The basic characteristics of emulsion (interfacial tension, droplet size, viscosity, and microstructure), gel properties (viscoelasticity) and stability of emulsion under extreme temperature (creaming index, appearance, and encapsulation stability) were evaluated. The addition of κ-Car and MC decreased the droplet size and increased the viscosity of emulsion as well as formed the thick protective coating. Also, the gelling temperature (T g) of emulsion containing κ-Car showed at low temperatures below 20 °C, while the T g of emulsion containing MC showed at high temperatures above 56 °C. Therefore, according to the results of creaming index and encapsulation stability under heating (80 °C for 30 min) and freezing-thawing (−18 °C and −60 °C for 3 d) treatment, the mixed system with κ-Car and MC greatly improved the stability, especially in DE system. These results suggest that the gelled emulsions mixed with κ-Car and MC were very stable under extreme temperatures such as the cooking and frozen storage and may be utilized to animal fat replacements and other industries. [Display omitted] • The existence of MC greatly increased the heat stability of the emulsion. • The existence of κ-Car greatly increased the freeze-thaw stability of the emulsion. • The double emulsion mixed with κ-Car and MC can provide high stability. • Enhanced the stability of double emulsion-type fat replacement even in the cooking and frozen storage. [ABSTRACT FROM AUTHOR]

Among modified Poly(propylene)s (PPs) grafted with polar monomers, PP grafted with maleic anhydride (PP- g-MAH) is known to be the most efficient compatibilizer for PP/clay nanocomposites, since it provides well-dispersed nanostructures and yields optimal physical properties of the nanocomposites. One drawback of this material, however, is that it becomes brittle and its viscosity decreases drastically, leading to nanocomposites with low toughness as the graft degree of MAH increases. Therefore, there is a limitation to increasing both stiffness and toughness of PP/clay nanocomposites with PP- g-MAH. In this study, we investigated the performance of a PP grafted with maleic anhydride and styrene (PP- g-MAH-St) as compatibilizers in PP/clay nanocomposites. It was found that the incorporation of styrene as a comonomer prevents molecular weight reduction of the PP main chain upon high loading of a radical initiator for high graft degree of MAH. The compatibilizers (PP- g-MAH-St) thus obtained show good compatibilizing performance in PP/clay nanocomposites. The PP/clay nanocomposites compatibilized by PP- g-MAH-St show both high stiffness and toughness, which is accomplished by using a compatibilizer of higher viscosity compared with PP- g-MAH. [ABSTRACT FROM AUTHOR]