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[Display omitted] • Droplet interactions tune emulsion rheology from soft-solid to glassy- to gel-like • LAOS rheology mapped over broad range of droplet-droplet interactions • Current system of emulsion rheology characterisation might not be sufficient We hypothesise that interaction strength between oil droplets determine the rheological properties of oil-in-water (O/W) emulsions by simultaneous formation and break-up of bonds between droplets. Using small (SAOS) and large (LAOS) amplitude oscillatory shear measurements, we aim to distinguish different classes of emulsions based on the specific microstructural evolution of the emulsions. Concentrated O/W emulsions differing in droplet-droplet interaction strength were obtained. Different interaction strength was obtained using different types of interactions; (a) electrostatic attraction, (b) salt bridging, or (c) crosslinking. In line with our hypothesis, different rheological events in emulsions depend on the droplet-droplet interaction strength. Strong interactions lead to monotonous yielding, and droplets undergo jamming or densification to provide strain hardening and gel-like behaviour. Emulsions with weak interactions exhibit two-step yielding (SAOS) and continuous yielding in LAOS; indicating a soft-glassy material. In emulsions above maximum packing, and with weak interactions the rheology is controlled by cluster/cage breaking, and transient formation of new clusters. For medium-strength interactions, two-step yielding was reduced, and apparent stain-hardening occurred. The probability of two distinct time scales of yielding is hindered by stronger interactions and jamming. Overall, in concentrated emulsions, yielding is determined by network rupture and reformation, cluster rearrangement and -breaking, which in turn is influenced by interaction type and strength. We present a more differentiated categorisation of emulsions based on interaction strength. [ABSTRACT FROM AUTHOR]

The suitability of oil-in-water (o/w) hydroxypropyl methylcellulose (HPMC)-based emulsions and oleogels to reduce total fat and saturated fat content in cream cheese was studied. The effect of HPMC emulsions and oleogels on spreadability, viscoelasticity, and sensory acceptability of cream cheese was evaluated. Small-amplitude oscillatory shear (SAOS) and large-amplitude oscillatory shear (LAOS) tests were performed to investigate linear and nonlinear rheology. All cheeses showed a predominance of G' versus G" with a light dependence of both moduli with frequency in the linear viscoelastic region (LVR). Fat replacement with emulsion or oleogel significantly reduces the values of G' and G" at the LVR, yield point, and flow point, and increases spreadability. This effect was greatest for the oleogel substitution. However, incorporation of emulsion or oleogel did not significantly affect tan δ, yield stress, yield strain, flow stress, and flow strain. The elastic and viscous evolution during the transition from SAOS to LAOS was similar in all cheeses, despite their differences in spreadability. At large deformation, all samples showed strain-stiffening and shear-thinning behavior. Similar sensory acceptability was found among the oleogel and emulsion cheeses and the control. The similar nonlinear rheological properties among cheeses do not explain the differences in spreadability properties, but explain their similar sensory acceptability. Furthermore, the purchase intention for oleogel and emulsion cheeses increases when consumers receive information on the type and amount of fat. [Display omitted] • Emulsion or oleogel can improve the spreadability of cream cheese. • A cream cheese with reduced fat content and improved lipid profile was achieved. • Emulsion or oleogel did not significantly affect rheology of cheese. • Consumption intention of emulsion or oleogel cream cheese increased. [ABSTRACT FROM AUTHOR]

[Display omitted] • Structural distinction of oleogel-based emulsion was confirmed by rheological technique. • Formation of crystal networks in emulsion was investigated by temperature sweep test. • Chebyshev coefficients analysis of LAOS showed that yielding was a broad transition. • Viscoelastic properties of oleogel-based emulsion were improved by modulating external factors. This study reported oleogel-based emulsions (OGEs, W/O) stabilized by carnauba wax. The effects of different external factors (heating temperature, crystallization temperature, and shear application during crystallization) on the microstructure and linear/nonlinear rheological properties of OGEs were investigated. Microstructural observation suggested that the OGEs had a uniform droplet distribution, and the carnauba wax crystals trapped oil in the continuous phase. The gelatinized oil phase allowed the OGEs to have a solid appearance and typical yielding behavior. The small amplitude oscillation shear analysis showed that lower heating temperature, higher crystallization temperature, and suitable shear application resulted in a stronger, more stable, and tighter packed network structure and better resistance to deformation of the OGEs. For nonlinear behavior, the elastic dominant behavior of OGEs transformed into viscous dominant behavior at large strain amplitudes, accompanied by more energy dissipation, strain stiffening, and a transition from shear thickening to shear thinning. [ABSTRACT FROM AUTHOR]

Clay particles (montmorillonite) induced stabilization in oil–water emulsions in different ways depending on their localization. Regardless of the localization, an emulsion showed a plateau in G′ and a local peak in G″ under small strain. During large-amplitude shear tests, an emulsion with clays selectively localized in the oil phase demonstrated local minima in G′ and G″ while an emulsion with an interfacial layer of clays showed a strain thinning behavior. The strain thinning behavior of the emulsion substantially occurred due to strain thinning behavior of the viscoelastic interfacial layer. The interfacial layer of particles of high concentration provided higher yield stress and shear thinning in the emulsion because it had a higher modulus and rapid thinning behavior compared to a layer of particles of low concentration. Using interfacial rheology, the bulk rheological response of the emulsion could be linked to the mechanical properties of the interfacial layer. [ABSTRACT FROM AUTHOR]

This paper aimed to examine the effect of using aquafaba in different ratios (25%, 50%, 75%, 100%) as an egg yolk substitute on the physical, structural, and rheological properties of mayonnaise. Large amplitude oscillatory shear analysis (LAOS) parameters (η L ′, η M ′ , G' L , G' M , e 3 , e 1 , v 3 , v 1) were evaluated to determine the rheological properties of mayonnaise samples. The droplet size of samples significantly increased and the stability of the emulsion decreased after 50% substitution ratio. The density of mayonnaise significantly increased with increased aquafaba substitution. According to Lissajous curves, egg yolk substitution with aquafaba leads to a decrease in stress values. Aquafaba affected the microstructure of samples and decreased the dissipated and stored energies. The LAOS parameters showed that the sample's behavior is strain stiffening and shear thinning in the nonlinear region. Textural parameters decreased with increased ratio of aquafaba. Significant differences were observed for L*, a*, b* and ΔE values. • The study analyzed the effects of using aquafaba as an egg substitute in mayonnaise. • Droplet size increased while stability, textural parameters decreased with aquafaba. • Nonlinear rheological properties of mayonnaise samples were determined by LAOS. • LAOS parameters were used to interpret nonlinear rheological behavior of samples. • Lissajous curves showed that stress values decreased on increasing aquafaba amount. [ABSTRACT FROM AUTHOR]