Small Amplitude Oscillatory Tests Research Articles

Rheological Properties and Physical Stability of Aqueous Dispersions of Flaxseed Fibers.

The main objective of this work is to investigate the influence of shear on the rheological properties and physical stability of aqueous dispersions of flaxseed fiber. The variable to consider will be the homogenization rate in two different rotor-stator homogenizers, Ultraturrax T50 or T25. In order to achieve the proposed objective, small amplitude oscillatory tests, flow curves, and multiple light scattering measurements were carried out. All samples exhibited a shear thinning behavior that was not influenced by the shear imposed, and a weak gel-like behavior. The latter, unlike the flow behavior, was sensitive to the homogenization rate. Thus, an increase in this variable caused a decrease in the viscoelastic moduli values. This result pointed out a weakening of the network formed by the flaxseed fiber in an aqueous medium. On the contrary, the physical stability improved. Nevertheless, all samples were highly stable. The homogenizer used was a significant variable. The shear negatively influenced the microstructure of the aqueous flaxseed fiber dispersions, although the obtained gels were highly stable. The gel-like behavior, the high viscosity at low shear rates, and the high physical stability of the samples studied make them interesting food stabilizers and thickeners.

The Effect of pH on the Viscoelastic Response of Alginate-Montmorillonite Nanocomposite Hydrogels.

Ionically cross-linked alginate hydrogels are used in a wide range of applications, such as drug delivery, tissue engineering, and food packaging. A shortcoming of these gels is that they lose their strength and degrade at low pH values. To develop gels able to preserve their integrity in a wide range of pH values, Ca-alginate-montmorillonite nanocomposite gels are prepared, and their chemical structure, morphology, and mechanical response are analyzed. As the uniformity of nanocomposite gels is strongly affected by concentrations of MMT and CaCl2, it is revealed that homogeneous gels can be prepared with 4 wt.% MMT and 0.5 M CaCl2 at the highest. The viscoelastic behavior of nanocomposite gels in aqueous solutions with pH = 7 and pH = 2 is investigated by means of small-amplitude compressive oscillatory tests. It is shown that Ca-alginate-MMT nanocomposite gels preserve their integrity while being swollen at pH = 2. The experimental data are fitted by a model with only two material parameters, which shows that the elastic moduli increase linearly with a concentration of MMT at all pH values under investigation due to formation of physical bonds between alginate chains and MMT platelets. The presence of these bonds is confirmed by ATR-FTIR spectroscopy. The morphology of nanocomposite gels is studied by means of wide-angle X-ray diffraction, which reveals that intercalation of polymer chains between clay platelets increases the interlayer gallery spacing.

The Effect of Temperature on the Mechanical Properties of Alginate Gels in Water/Alcohol Solutions.

Alginate organohydrogels prepared in water/alcohol mixtures play an important role in electronic and superconductor applications in low-temperature environments. The study deals with the preparation of Ca-alginate organohydrogels and the analysis of their equilibrium swelling and mechanical properties at sub-zero temperatures. It is shown that the equilibrium degree of swelling at room temperature is noticeably affected by the concentration of co-solvents (methanol, ethanol, and 2-propanol) in the mixtures and the number of carbon atoms in the co-solvent molecules. Mechanical properties are studied in small-amplitude oscillatory tests. The data are fitted with a model that involves three material parameters. The influence of temperature is investigated in temperature-sweep oscillatory tests under a cooling-heating program, where a noticeable difference is observed between the storage and loss moduli under cooling and heating (the hysteresis curves). The hysteresis areas are affected by the cooling/heating rate and the number of carbon atoms in the co-solvents.

Mechanical Properties of Alginate Hydrogels Cross-Linked with Multivalent Cations.

Ionically, cross-linked alginate gels have a potential to be used in a wide range of biomedical, environmental and catalytic applications. The study deals with preparation of alginate hydrogels cross-linked with various cations and the analysis of their equilibrium swelling and mechanical properties. It is shown that the type of cations used in the cross-linking process affects the elastic moduli and the equilibrium degree of swelling of the gels. The experimental data in small-amplitude oscillatory tests are fitted with a model that involves two material parameters: the elastic modulus of a polymer network and a measure of its inhomogeneity. The influence of cations on these quantities is studied numerically. It is revealed that the dependence of the elastic modulus of ionically cross-linked alginate gels on their equilibrium degree of swelling differs from that predicted by the conventional theory for covalently cross-linked gels.

The effects of freeze-thaw cycles on the rheological properties of yeasted and non-yeasted frozen bread doughs

The effects of repeated freeze-thaw cycles on yeasted and non-yeasted frozen bread doughs were investigated by a series of fundamental rheological tests, including small stress amplitude oscillatory test, shear creep-recovery, and uniaxial and planar extensional tests. Results showed that yeasted and non-yeasted doughs tested under both shear and extension using small and large deformations were rheologically different. Yeasted dough exhibited significantly higher storage modulus (G’) as measured by the small stress amplitude oscillatory test and lower compliance measured in creep recovery tests. The effects of freeze-thaw cycles were clearly displayed in non-yeasted doughs, especially in large deformations rheological tests. Resistance to deformation of non-yeasted dough was altered by freeze-thaw cycles, indicated by creep recovery tests conducted under 500 Pa creep stress. The extension failure stress of non-yeasted dough was affected by freeze-thaw cycles, indicated by uniaxial and planar extensional tests. The negative impact of freeze-thaw cycles in yeasted doughs was more pronounced for dough examined with extensional tests. This was revealed by a decreased strain hardening behavior of doughs after freeze-thaw cycles when tested by uniaxial and planar extensional tests. Large deformation tests, particularly under extensional deformations can assist in the understanding of the freeze-thaw impact on dough matrices.

Acid and rennet gelation properties of sheep, goat, and cow milks: Effects of processing and seasonal variation

Gelation is an important functional property of milk that enables the manufacture of various dairy products. This study investigated the acid (with glucono-δ-lactone) and rennet gelation properties of differently processed sheep, goat, and cow milks using small-amplitude oscillatory rheological tests. The impacts of ruminant species, milk processing (homogenization and heat treatments), seasonality, and their interactions were studied. Acid gelation properties were improved (higher gelation pH, shorter gelation time, and higher storage modulus (G') by intense heat treatment (95°C for 5 min) to comparable extents for sheep and cow milks, both better than those for goat milk. Goat milk produced weak acid gels with low G' (<100 Pa) despite improvements induced by heat treatments. Seasonality had a marked impact on the acid gelation properties of sheep milk. The acid gels of late-season sheep milk had a lower gelation pH, no maximum in tan δ following gel formation, and 70% lower G' values than those from other seasons. We propose the potential key role of a critical acid gelation pH that induces structural rearrangements in determining the viscoelastic properties of the final gels. For rennet-induced gelation, compared with cow milk, the processing treatments of the goat and sheep milks had much smaller impacts on their gelation properties. Intense heat treatment (95°C for 5 min) prolonged the rennet gelation time of homogenized cow milk by 8.6 min (74% increase) and reduced the G' of the rennet gels by 81 Pa (85% decrease). For sheep and goat milks, the same treatment altered the rennet gelation time by only less than 3 min and the G' of the rennet gels by less than 14 Pa. This difference may have been caused by the different physicochemical properties of the milks, such as differences in their colloidal stability, proportion of serum-phase caseins, and ionic calcium concentration. The seasonal variations in the gelation properties (both acid and rennet induced) of goat milk could be explained by the minor variation in its protein and fat contents. This study provides new perspectives and understandings of milk gelation by demonstrating the interactive effects among ruminant species, processing, and seasonality.

Thermal and Thermal-Oxidative Molecular Degradation of Polystyrene and Acrylonitrile Butadiene Styrene during 3D Printing Starting from Filaments and Pellets

An important polymer processing technique is additive manufacturing (AM), which enables shape-free design of complex final parts with limited waste during the development change, at least if the impact of molecular degradation reactions is minimized. In the present work, polystyrene (PS) and acrylonitrile butadiene styrene (ABS) polymer have been processed via: (i) fused filament fabrication (FFF), separately accounting for the prior single screw extrusion (SSE) filament production; and (ii) pellet-based additive manufacturing (PBAM), which are two important AM techniques. The influence of printing temperature, layer thickness, printing velocity, and printing technique on the degradation of both polymeric materials is studied by means of thermogravimetric analysis (TGA), size exclusion chromatography (SEC), small amplitude oscillatory shearing tests (SAOS), Fourier-transform infrared spectroscopy (FTIR), and yellowness index (YI) measurements. For ABS, SSE-FF leads to more fission (higher mechanical loading) whereas PBAM results in more cross-linking (more thermal loading). For PS, fission is always dominant and this more evident under FFF conditions. ABS also exhibits yellowing upon processing, indicating thermo-oxidative degradation although below the FTIR sensitivity limit. The selected PBAM conditions with PS are already delivering printed specimens with good mechanical properties and lower degradation. For ABS, a further PBAM optimization is still desired compared to the FFF countercase, taking into account layer-by-layer adhesion.

Shear and dilatational rheological properties of vegetable proteins at the air/water interface

Many food products are multiphase systems and their structural and textural properties are determined by the amount and the characteristics of the different ingredients making up the system. They are created by homogenization of two or more immiscible phases, to form emulsions or foams. Proteins are widely used to stabilize the interfaces of these types of system because they have high nutritional value and they are able to adsorb quickly at the interface decreasing the interfacial tension and improving the mechanical resistance. Recently, proteins extracted from vegetable seeds have been receiving much attention from the food industry, thanks to their good environmental sustainability and healthy composition, but the scientific literature is lacking in information on the surface activity and emulsifying ability of these proteins. In this work, the surface properties of three different proteins extracted from vegetable sources (soy, hemp and brown rice seeds) were investigated using interfacial shear and dilatational kinematics. Linear viscoelastic properties were evaluated using small amplitude oscillatory tests (about 10%ΔV/V and 2% for dilatational and shear deformation, respectively); in addition, stress relaxation after quick expansion/compression and shear creep were also used to obtain information about the viscoelasticity and the characteristic time of relaxation of the interfacial film. The three proteins displayed excellent interfacial properties similar among them. Brown rice protein yields stronger interfacial layers whereas soy is more liable to structure the interface and hemp exhibits intermediate properties. Obtained results demonstrate that brown rice and hemp proteins could be used to obtain food multiphase systems, like foams, without the addition of surfactants or animal proteins, thanks to their interfacial characteristics, and they can yield a high nutritional content thanks to their amino acid profile.

Magneto-rheology control in 3D concrete printing: A rheological attempt

The application of magneto-rheology control in extrusion-based 3D concrete printing is conceptually examined by rheological experiments on cementitious paste with nano-Fe3O4. The extruding process is simulated by a constant shearing, and the buildability after extrusion is characterized by the structural build-up from small amplitude oscillatory time-sweep test. A pulsed magnetic field is applied during shearing and then removed when the shearing terminates. It is revealed that some residual magnetic clusters exist in the suspension after removing the magnetic field due to the remanent magnetization of the nanoparticles. This results in a faster structural build-up compared to the situation without being treated by magnetic field, and this is independent of the magnetic field duration within the considered range from 1 s to 5 s. This finding offers an innovative methodology to actively improve the buildability of 3D printed concrete by introducing a short-pulsed magnetic field during extrusion.

Novel high internal phase emulsions with gelled oil phase: Preparation, characterization and stability evaluation

Novel high internal phase emulsions (HIPEs, O/W) with gelled oil phase were fabricated via a facile approach using all-natural ingredients. Oil phase of HIPEs was oleogelated with beeswax (BW), and the effects of BW concentration (0–6%) on structural properties of the emulsions and stability of β-carotene were highlighted. Microstructural observation indicated that the oil droplets (3–4 μm) of the emulsions were tightly packed with protein bridges at the interfaces and BW crystals inside the droplets. BW crystals were also confirmed by XRD analysis, and the increase in BW concentration led to higher crystallinity in HIPEs. Oleogelation of the oil phase offered the emulsions with improved stability against centrifugation, heating and freeze-thawing, and the HIPE with 3% BW presented the best stability. Small amplitude oscillatory shearing tests revealed that storage modulus of the samples was dependent on BW concentration, and creep-recovery evaluation indicated that the HIPEs with BW had higher resistance over deformation. Large amplitude oscillatory shearing tests showed that the HIPEs with higher content of BW (4.5, 6%) had stain thinning behavior, while those with lower content of BW (0, 1.5, 3%) presented weak strain overshoot characteristics. When β-carotene (up to 2.25%) was incorporated in the oil phase of the emulsions, its stability against light and thermal treatment was significantly improved with the presence of BW, and the emulsion with 3% offered the highest protection. These information suggested that oleogelation of the oil phase facilitated the formation of stable HIPEs and can better behave as carriers for liable bioactives.

Antagonistic effects of amylopectin and amylose molecules on the starch inter- and intramolecular interactions during retrogradation

Starch retrogradation property is critical for developing functional foods with desirable nutritional and textural attributes, while its nature currently remains elusive. The current study investigated the relations between starch chain-length distributions (CLDs) and interaction patterns (i.e. intermolecular versus intramolecular interactions) of starch molecules during the retrogradation process. CLDs for different waxy potato and sago starch mixtures were characterized by size-exclusion chromatography, and molecular interactions were characterized by differential scanning calorimetry and small amplitude oscillatory shear rheological test. Results for the first time showed that amylose molecules were involved in the formation of short-range intermolecular interactions with amylopectin molecules. Most intermolecularly heterogenous double helices were formed at the 1 : 1 mixing ratio of waxy potato to sago starch. Although the addition of waxy potato starch to sago starch increased the overall amount of short-range double helices, the amount of short-range intermolecular double helices was decreased. It suggests that there was an antagonistic effect between the formation of short-range inter- and intramolecular double helices. These results help a better understanding of the interaction patterns of amylose and amylopectin molecules during the retrogradation process.

Thermo-Viscoelastic Response of Protein-Based Hydrogels.

Because of the bioactivity and biocompatibility of protein-based gels and the reversible nature of bonds between associating coiled coils, these materials demonstrate a wide spectrum of potential applications in targeted drug delivery, tissue engineering, and regenerative medicine. The kinetics of rearrangement (association and dissociation) of the physical bonds between chains has been traditionally studied in shear relaxation tests and small-amplitude oscillatory tests. A characteristic feature of recombinant protein gels is that chains in the polymer network are connected by temporary bonds between the coiled coil complexes and permanent cross-links between functional groups of amino acids. A simple model is developed for the linear viscoelastic behavior of protein-based gels. Its advantage is that, on the one hand, the model only involves five material parameters with transparent physical meaning and, on the other, it correctly reproduces experimental data in shear relaxation and oscillatory tests. The model is applied to study the effects of temperature, the concentration of proteins, and their structure on the viscoelastic response of hydrogels.

Effect of pre-shearing on the steady and dynamic rheological properties of mud sediments

Mud sediments can exhibit a complex rheological behaviour particularly a thixotropic character or structural recovery after breakup due to the presence of organic matter/biopolymer. Such biopolymers can lead towards the development of flocculated structures having multiple length scales which are sensitive to shearing rate and history. In this study, the extent and rate of structural recovery of mud sediments was studied by measuring the storage modulus as a function of time using small amplitude oscillatory tests after a destructive steady shearing. This linear viscoelastic response of the sediments was further investigated as a function of several parameters including pre-shear rate, pre-shear time, measuring geometry, mud density and organic matter content. The equilibrium storage modulus (G∞') and the characteristic time (tr) for the structural recovery of the sediment matrix were estimated by fitting the experimental data to a stretched exponential function. The normalized storage modulus, G'/G0' (i.e., structural parameter) was used to relate it with the yield stresses of mud sediments. The results showed that the recovery of structure after shearing was instantaneous (tr being of the order of seconds), however, the extent of recovery was highly dependent on the studied parameters. The extent of recovery was higher for the samples with lower density and lower organic matter content. The effect of the shearing time on tr and G∞' was almost negligible, which implies that the destruction of the structure was achieved within seconds. Using vane geometry, the extent of recovery was higher than using Couette geometry which is linked with the distribution of shear stresses within the cell for each geometry. Yield stresses showed a strong dependency on structural parameter, until it reaches very small values. At low values of structural parameter, the yield stresses were constant as the structural recovery was even faster than the time required to perform the amplitude sweep tests. This study provides an extensive knowledge about the structural recovery in mud sediments under different shearing conditions which can be useful for sediment management.

Non‐linear rheological response as a tool for assessing dispersion in polypropylene/polycaprolactone/clay nanocomposites and blends made with sub‐critical gas‐assisted processing

Polypropylene (PP) was blended with polycaprolactone (PCL) and nanoclay (NC) in a twin‐screw extruder (TSE) using a traditional extrusion process and a sub‐critical gas‐assisted process (SGAP). SGAP is a new and facile processing method that injects compressed gas (CO2 or N2) at low pressures (~10 bars) into the barrel of the extruder to induce rapid and repetitive foaming and resolubilization as the melt travels through regions of high pressure and low pressure. Bubble expansion during foaming introduces an equibiaxial elongational flow not otherwise generated in TSE, adding to the total stress the polymer matrix can exert to break up nanoparticle agglomerates and reduce the droplet size of secondary polymers in blends. Impact, morphology, and X‐ray diffraction (XRD) properties confirmed a smaller PCL phase droplet size and an increase in dispersion of the NC when SGAP was used. Standard small amplitude oscillatory (SAOS) rheological tests for the storage modulus G′ were not sensitive enough to discern the difference between the traditionally extruded samples and the SGAP samples. However, the zero‐strain non‐linearity parameter, Q0, determined by the Fourier‐Transform rheology, was able to distinguish the enhanced dispersive and mixing capabilities of SGAP. Practical implications of SGAP and Fourier‐Transform (FT) rheology are also discussed in this paper. POLYM. ENG. SCI., 60:55–60, 2020. © 2019 Society of Plastics Engineers

Mechanical properties of polymeric microfiltration membranes

The influence of the pore topology and polymer properties on mechanical characteristics of asymmetric polyethersulfone (PES) and symmetric polyvinylidene fluoride (PVDF) microfiltration membranes was investigated by conducting elongation, creep, stress relaxation, small-amplitude oscillatory and bubble point pressure tests. The main aspects of the membrane stress-strain curves were found to be similar despite significant differences in the pore topology and polymer properties. While the Kelvin-Voigt model for solid polymers described the membrane viscoelastic response below the transition to ductile yielding, the stress-strain curves of membranes and solid polymers above the yield point appeared to be drastically different. All tested membranes demonstrated weak strain hardening, low sensitivity to strain rate, significant elastic recovery, stress relaxation and reduction of the bubble point pressure with accumulation of plastic deformation. Therefore, tensile stresses exerted on a membrane under assembling and process conditions should be smaller than the yield stress to assure that they will not impair filter performance. The novelty of our approach is the use of models for perforated plates to evaluate membrane mechanical properties as ductile yielding for both proceeds via localized plastic deformation around pores. Presented results provide a reliable framework for development of membranes with properties tailored to applications.

Non-linear rheological (LAOS) behavior of sourdough-based dough

During processing, wheat dough is known to undergo large deformation led by mixing and fermentation processes. This deformation is much more pronounced when sourdough is used in the recipe of wheat dough whose gluten is considerably hydrolyzed during sourdough fermentation. This causes deeper effects on rheological properties and shelf life of bakery products. Traditional small amplitude oscillatory tests do not enable us to comprehend the viscoelasticity under large deformations. In this respect, large amplitude oscillatory shear (LAOS) tests are useful for accurate characterization of the non-linear mechanical response. This study, therefore, is undertaken to investigate the non-linear mechanical response of dough prepared with different amounts of sourdough (0, 10, 20 30 and 40%) in a strain values ranging from 0.005 to 200% (frequency at 10 rad/s). As a result, sourdough was determined to have considerable effects on the non-linear viscoelastic response of dough. Strain-stiffening and shear-thinning behaviors were considerably influenced by sourdough incorporation and the dough started to show strain-softening and lowered shear-thinning behavior after giving a peak around at 100% strain due to the onset of the breakdown of the gluten network and suspension of starch matrix as consequence of the metabolic activity of the starter culture (Lactobacillus brevis E25) used in the preparation of sourdough. The physicochemical (pH and TTA), microbiological properties (LAB count) and extensographic properties were also shown to support the LAOS results. LAOS tests could be effectively and clearly used to reveal the effect of processing conditions (sourdough content and deformation by large strain amplitude) on the non-linear mechanical response of wheat dough.

Viscoelastic Properties of Thixotropic Semisolid Alloy Relating the Microstructure

The subject of this work is to investigate viscoelastic properties such as loss modulus (G ́ ́), storage modulus (G ́), complex shear modulus (G*), complex viscosity (η*) and loss angle () at different temperatures by means of a small-amplitude oscillatory test. These properties allow to provide information about materials structure. For this purpose, we employed a tin-lead alloy (Sn-15%Pb) which exhibits a similar microstructure to aluminum alloys and is the classic alloy for semisolid thixotropic studies. It is interesting to note that the Sn-15%Pb alloy exhibits a slightly decrease in storage modulus (G ́) over the entire frequency (0.01-10Hz) at high temperatures, showing its viscoelastic behavior. In addition, a detailed analysis of master curves (oscillatory tests) was made to relate the semisolid microstructure (solid fraction) with the plateau modulus (GN0) which is directly related with both molecular weight or percolation threshold in polymer and gels science respectively.

Effect of leavening time on LAOS properties of yeasted wheat dough

Wheat dough is subjected to large deformations under realistic processing conditions. The viscoelasticity under large deformations can be hardly captured by traditional small amplitude oscillatory tests. Large amplitude oscillatory shear (LAOS) tests are required for accurate characterization of the nonlinear mechanical response. In this regard, LAOS studies of yeasted wheat dough leavened at different times (0, 30, 60, 90 and 120 min) were carried out in this work, in the strain range from 0.1% to 100% (frequency 2π rad/s). All the dough samples showed a complex rheological response that was characterized by strain stiffening and shear thinning behavior at large strains. FTIR analysis revealed that starch granules were increasingly hydrated and protein molecular configuration was modified by the yeast activity. It was postulated that modifications of the protein secondary structure can be behind the strain stiffening behavior while the suspended starch matrix was associated with the shear thinning behavior. LAOS enabled to disaggregate the viscoelasticity of the wheat dough to assess the nonlinear effects associated with elasticity and energy dissipation mechanisms. Overall, a longer leavening time increased by about 30% the nonlinear mechanical response of wheat dough, an effect probably induced by variations in the secondary structure of wheat proteins and to the gassing of the dough microstructure as consequence of the yeast metabolic activity. The results in this work showed that LAOS is a suitable method for characterization of the nonlinear mechanical response of whet dough, especially for assessing the effect of processing conditions (e.g., leavening time and yeast content).

치즈 물성의 객관적 측정을 위한 고찰

The textural and rheological properties of cheese are major attributes for the characterization of cheese types, ripening, and consumer preferences. The use of small amplitude oscillatory rheological testing has made it possible for cheese researchers to assess the major properties of cheese, such as melting behavior and storage modulus, without irreversible deformation. In addition, large deformation testing such as textural profile analysis can assess properties such as hardness of cheese. While the sensory properties of cheese are valued by consumers, objective and reliable measurements are paramount for researchers. Ongoing development and refinement of scientific measurement methods of cheese are vital.

Effects of processing conditions on the texture and rheological properties of model acid gels and cream cheese

Manufacture of cream cheese involves the formation of an initial acid-induced gel made from high-fat milk, followed by a series of processing steps including shearing, heating, and dewatering that complete the conversion of the acid gel into a complex cheese product. We investigated 2 critical parameters for their effect on the initial gel: homogenization pressure (HP) of the high-fat cheese milk, and fermentation temperature (FT). The impact of a low (10 MPa) and high (25 MPa) HP, and low (20°C) and high (26°C) FT were investigated for their effects on rheological and textural properties of acid-induced gels. Intact acid gels were sheared and heated to 80°C, and then their rheological properties were analyzed to help understand the effect of shearing/heating processes on the gel characteristics. The effect of HP on fat globule size distribution and the amount of protein not involved in emulsion droplets (i.e., in the bulk phase) were also studied. For cream cheese trials, a central composite experimental design was used to explore the effect of these 2 parameters (HP and FT) on the texture, rheology, and sensory properties of experimentally manufactured cream cheese. Storage modulus (G') and hardness values of cream cheeses were obtained from small amplitude oscillatory rheology tests and texture profile analysis, respectively. Quantitative spectrum descriptive sensory analysis was also performed. Consistency of acid gels (measured using a penetration test) increased with an increase in FT and with an increase in HP. Although stiffer acid-induced gels were formed at high FT, after the heating and shearing processes the apparent viscosity of the samples formed at high FT was lower than those formed at low FT. For the cream cheeses, significant prediction models were obtained for several rheological and textural attributes. The G' values at 8°C, instrumental hardness, and sensory firmness attributes were significantly correlated (r > 0.84); all these attributes significantly decreased with an increase in FT, and HP was not a significant parameter in the prediction models developed for these attributes. Significant interactions were observed between the HP and FT terms for these prediction models. Higher HP increased the amount of protein adsorbed at interface of fat globules but decreased bulk phase protein content (which may be important for crosslinking this gelled emulsion system). At higher FT temperature, coarser gel networks were likely formed. The combined effect of a coarser acid gel network at high FT, and less bulk phase casein available for crosslinking the acidified emulsion gel with an increase in HP, could have contributed to the lower stiffness/firmness observed in cream cheese made under conditions of both high FT and high HP. Stickiness of cream cheese greatly increased under conditions of high FT and high HP, whereas the sensory attributes cohesiveness of mass and difficulty to dissolve decreased. This study helped to better understand the complex relationships between the initial acid-induced gel phase and properties of the (final) cream cheese.