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This study aimed to develop a high-performance asphalt mixture resistant to rutting through modification with industrial-scale graphene nanoplatelets (industrial GNPs). To achieve this objective, industrial GNPs were incorporated into an SBS-modified asphalt binder at concentrations of 2%, 4%, 6%, 8%, and 10% by mass of the asphalt binder. The aim was to select a design content to enhance the rutting performance of the resulting asphalt mixture. The nanomaterial content selection criterion was based on apparent viscosity results and rheological parameters (MSCR). Two asphalt mixtures were produced after determining the nanomaterial content: a reference mixture and another modified by the selected content (2.64% of industrial GNPs). The mechanical performance was assessed through resistance to rutting tests on French Orniéurer equipment and, in a secondary character, the fatigue resistance under four-point bending. The results showed better rheological behaviour of the modified composites than of the original binder, decreasing the viscous response at high temperatures and thus reducing the non-recoverable deformations. The resistance to rutting of the modified mixture exceeded that of the reference mixture by 19% (mean rut for 30,000 cycles) without significant damage to the fatigue life, proving the high rutting performance of the alternative asphalt mixture. [ABSTRACT FROM AUTHOR]

BACKGROUND: The incorporation of functional food ingredients in chocolate that seek to eliminate, if not completely, most of the added sugar content, as well as the use of alternative chocolate production techniques, have gained popularity in recent years. This study aimed to incorporate red beetroot powder into dark chocolate and investigate the effect of red beetroot powder concentration and processing time in a melanger on the physicochemical properties, sensory profile and consumer acceptability of beetroot dark chocolate. RESULTS: The addition of red beetroot powder increased the moisture content, particle size distribution and hardness of the chocolates, while the opposite was true for processing time with no effect on the colour. Except for taste, which had an average score of 3.2 ± 1.8 on the 7‐point hedonic scale, consumers scored all the other sensory attributes of the chocolates above 4.0. Among the chocolates with red beetroot powder, samples with a 15% red beetroot powder addition had a high average overall acceptability score of >5, while the 30% sample scored <4. CONCLUSION: Red beetroot powder can be used to replace sugar in dark chocolate without affecting its physicochemical properties, sensory profile or consumer acceptability. However, the target market should be considered when determining the level of red beetroot powder incorporation in terms of chocolate taste. This research has the potential to improve the overall health‐promoting properties of dark chocolate by eliminating added sugar (partially or completely). It would also help to diversify beetroot utilization, allow small‐scale processors to venture into chocolate production and expand the small‐scale chocolate value chain. © 2024 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

This study prepared six different ice creams to investigate the effect of yeast protein (YP) on their sensory, rheological, thermal properties and fat destabilisation. Results indicated that YP could improve sensory quality, flow and viscoelastic properties. The thermal property was also positively influenced by YP with a significant decrease in frozen water percentage and an increase in glass transition temperature (P < 0.05). Additionally, the particle size and confocal laser scanning microscopy results illustrated that YP could moderately promote the fat aggregate percentage and size. Overall, YP could serve as a fat replacer to produce reduced‐fat ice cream. [ABSTRACT FROM AUTHOR]

In this present study, a three-factor Box–Behnken, response surface methodology (RSM) design was employed to optimize the skimmed milk powder (SMP)/whey protein concentrate (WPC) ratio (0.25–0.75%w/v) as a source of milk protein, inulin (1–2%w/v), and honey (4–6%w/v) for production of high-quality goat milk yoghurt (GMY). The resulting ANOVA and response surface equations revealed the significant effect (p < 0.05) of these variables on the various attributes such as total solid (%), pH, titratable acidity [(LA) % by weight], syneresis (%), DPPH (% inhibition), viscosity (m.Pa⋅s), whiteness index (WI), and overall acceptability (OA). The coefficient of determination (R2) for all response variables ranged from 0.88 to 0.99. Lack-of-fit tests resulted in non-significant F-values. The optimal conditions were determined as SMP/WPC at 0.36%w/v, inulin at 1.00%w/v, and honey at 6.00%w/v. The optimum values for total solid, pH, titratable acidity, syneresis, DPPH, viscosity, WI, and OA were 22.03, 4.46, 0.77, 6.34, 25.20, 182.30, 76.29 and 8.37, respectively with desirability value of 0.95. [ABSTRACT FROM AUTHOR]

Nanofluids (NFs) of fascinating multifunctional properties are the advanced materials highly admired in emerging soft device technologies. In this innovative research, we explored the detailed optical, dielectric, and rheological properties of silver ions conducting green NFs. These NFs comprise ethylene glycol (EG) as viscous base fluid, suspension of a fixed amount (0.02 wt%) aluminum oxide (Al2O3) nanoparticles for high performance thermal conductor, and addition of silver nitrate (AgNO3) salt as the ionic component of varying amounts ranging from 0.2 to 2.0 wt% are prepared and investigated. The detailed analysis of 200–800 nm wavelength range ultraviolet–visible (UV–Vis) absorbance spectra of these EG–Al2O3/AgNO3 based NFs demonstrated their significant photosensitivity character in the visible region, radiations shielding performance in the UV region, and trio energy band gaps in a wide semiconducting range from 2.4 to 4.9 eV which are found adequately tunable with the AgNO3 concentrations. The high static dielectric permittivity (εs ≈ 40) of these polar NFs, at 298.15 K, showed a marginal change with the variation in AgNO3 concentrations confirming a little alteration in the parallel aligned dipole ordering of hydrogen bonded EG molecular network beside the ion-molecules-nanoparticle interactions and formation of ion-dipole complexes (coordinative interaction). The electrical conductivity of EG–Al2O3 NF increased by three orders of magnitude i.e., from 10−6 to 10−3 S/cm, at the initial addition of 0.2 wt% AgNO3 in it and then, exhibited almost a linear increase with further increasing the salt concentrations up to 2.0 wt% realizes them promising ionic nanofluids. Rheological investigations on these NF samples, at 298.15 K, validate their Newtonian behaviour with a high dynamic viscosity of 14 mPa s. These experimental findings highlight the multifunctional characteristics of EG–Al2O3/AgNO3 nanofluids which could be utilized in heat transfer, solar energy harvesting/storage, and the development of next-generation iontronic and optoelectronic devices and silver ion conducting biomedical sensors.

Natural sepiolite has great potential for application in wound healing, haemostasis and medicines. This paper introduces a versatile solid-state sintering technique for preparing sepiolite-based nanocomposites with enhanced antibacterial properties, and the physical, structural, rheological and antibacterial properties of which were determined to be enhanced. The incorporation of nanosized Ag and metal oxides into sepiolite composites results in a notable improvement in their antibacterial efficacy against Escherichia coli and Staphylococcus aureus in comparison to the unmodified sepiolite. With a low silver content of just 5%, the sepiolite–Ag composite achieves an antibacterial rate of ~100%. Furthermore, the rheological properties exhibited by the sepiolite composites are noteworthy, suggesting their suitability for use in wound-dressing applications due to their exceptional workability. The methodology employed in this research has the potential to offer a viable substitute for the production of economical and effective natural antibacterial nanocomposites. [ABSTRACT FROM AUTHOR]

In the context of growing interest in plant-based food products for their potential health benefits and sustainability, this study investigates the effect of mono- and diglycerides of fatty acids application on physico-chemical properties of various plant-based cream products, compared to lecithin application in rice cream. Rheological and textural parameters, colour profile, and colloidal stability were analysed. The application of mono- and diglycerides modified the creams' viscoelastic behaviour, showing a decrease in viscoelasticity across the samples; although in oat–coconut cream resulted in a higher viscoelasticity, indicating the formation of a gel-like structure. Rice cream with lecithin emulsifier showed lower viscoelastic properties characterised by higher phase angle (tan δ). All samples behaved as pseudoplastic materials (with a flow behaviour index n < 1). For coconut and almond creams, the consistency coefficient increased and flow behaviour index decreased after emulsifier application. Interestingly, the emulsifier addition did not significantly affect the cream's colour profile, characterised by yellow hue angle (h*) as a dominant spectral component. The colloidal stability, indicated by a stability index (SI), was determined as well. [ABSTRACT FROM AUTHOR]

The present fused deposition modeling (FDM) printing process has concentrated on combining metal or ceramic filled with polymer because it could provide a strong composite in layered manufacturing technology in comparison to a single polymer material. However, the ability of the composite material to flow into the extruder becomes an obstacle because of the changes in the polymer concentration and dispersion of filler particles in producing the printed part. Hence, the rheological behavior of Hydroxyapatites (HAp) / Polylactic Acid (PLA) composite with different contents of HAp was studied to assess its ability to flow through the extruder during the 3D printing process. Measurements such as pycnometer density, thermal analysis (DSC) and FT-IR were performed on the composite feedstock containing a variation of 10% to 30% HAp powder. The feedstocks behavior then were characterized by rheological tests at three different temperatures (140 °C, 150 °C, and 160 °C). The composition of PLA/20HAp has produced optimum rheological behavior with effective flow behavior index (n) and activation energy (E) of 0.396 and 89.03 kJ/mol, respectively which is suitable for extruding out the HAp/PLA composite to become a 3D printing filament material. [ABSTRACT FROM AUTHOR]

The lotus seed and lily bulb beverage (LLB) has a problem with solid particle sedimentation. To address this issue, LLB was homogenised twice at different pressures (0~100 MPa) using a homogeniser. This study aims to investigate the changes in the particle size distribution (PSD), microstructure, rheological behaviour, sedimentation index (IS), turbidity, physicochemical properties, and sensory quality of LLBs after homogenisation treatments. The results regarding PSD and microstructure showed that the suspended particles were decomposed at high pressure with increasing homogenisation pressure, forming small particles of cellular material, cell wall fragments, fibre fractions, and polymers. The LLB showed shear-thinning behaviour and weak gelation characteristics (G′ > G″) and rheological properties. Among all homogenisation pressures, the 60 MPa sample showed the lowest sedimentation rate and the highest turbidity. When the pressure was increased from 0 to 100 MPa, the total soluble solid (TSS) content showed an upward trend, while the ascorbic acid content (AAC) gradually decreased. The highest sensory evaluation was observed in the 60 MPa sample in terms of overall acceptability. [ABSTRACT FROM AUTHOR]

This study explores the effect of various concentrations of Xanthan gum on the rheological behaviour of commercial mayonnaise. The various concentrations of Xanthan gum, ranging from 0.1 to 0.5% based on the weight of the mayonnaise which were mixed in the commercial mayonnaise via a high overhead stirrer at room temperature. The rheological characterizations were carried out on a Brookfield viscometer. Using Mitschka's method, the recorded data was changed into rheological parameters. Three rheological models, namely the Power-law model, Bingham model and Herschel-Bulkley model, used to determine the flow parameters of the samples. All the samples showed shear thinning behaviour at least in the shear rate used in this study. According to the goodness of fit (regression coefficient), the power law model was the best for determining flow parameters. It was observed that the consistency viscosity (K) increases with an increase in Xanthan gum concentration, at least for the concentration ranges used in this research. The higher value of K indicates that the mayonnaise becomes thick with Xanthan gum and will require higher yield stress to start flow. It was interesting to note that at 0.1% Xanthan gum concentration, the power index reached a plateau value of 0.1135. [ABSTRACT FROM AUTHOR]

Dehydroabietyl polyethylene glycol glycidyl ether-grafted hydroxyethyl cellulose (HEC) polymer surfactant (DA (EO)5GE-g-HEC) was prepared using ring-opening polymerization with biobased rosin and hydroxyethyl cellulose as feedstocks. Dehydroabietyl polyethylene glycol glycidyl ether (DA(EO)5GE) was formed by condensation of dehydroabietyl alcohol polyoxyethylene ether (Rosin derivative: DA(EO)5H) and epichlorohydrin. The grafting degree of DA(EO)5GE-g-HEC was manipulated by adjusting the mass ratio of HEC and DA(EO)5GE and confirmed by EA. According to the formula, when m(HEC)/m(DA(EO)2GE) was 1:1~1:5, the grafting rate of DA(EO)5GE in DA(EO)5GE-g-HEC varied from 34.43% to 38.33%. The surface activity and foam properties of DA(EO)5GE-g-HEC aqueous solution were studied. The results showed that with the increase in grafting rate, the critical micellar concentration (CMC) in aqueous solution changed from 1.28 to 0.96 g/L. The results of the thermogravimetric analysis showed that the temperature range of the main stage of mass loss of DA(EO)5GE-g-HEC was 310°C~410°C, and the thermal decomposition processes of the samples with five mass ratios were similar. An oil in water emulsion was prepared by choosing cyclohexane as the oil phase and DA(EO)5GE-g-HEC as the emulsifier. The effect of DA(EO)5GE-g-HEC mass fraction on emulsion particle size and stability was analyzed. The results suggested that when the oil-water ratio was 8:2 with 0.4% emulsifier, the emulsion droplets were the smallest in terms of particle size and were the most stable. The rheological test results showed that the apparent viscosity decreased with the increase in shear rate and showed a typical elastic gel phenomenon. [ABSTRACT FROM AUTHOR]

Bitumen emulsion, which is widely used for surface treatment and cold recycling in pavement engineering, has the advantage of not requiring heating during construction. But it has the disadvantage of low mechanical strength, especially at higher temperatures. Various studies have proved that waterborne epoxy can effectively improve the mechanical properties of bitumen emulsion. However, how aging affects the performance of waterborne epoxy resin-modified bitumen emulsion is still unclear. This study aims to fill this knowledge gap through combined rheological and microscopic characterisation. Fourier transform infra-red spectroscopy (FTIR) was first applied to characterise the oxidative reaction during the pressure aging vessel (PAV) test. The rheological behaviours before and after PAV aging were evaluated through dynamic shear rheometer (DSR) tests. The peak force tapping quantitative nanomechanical (PFT QNM) test was further conducted to measure the micromechanical performance of the waterborne epoxy bitumen emulsion residues. The results indicated that waterborne epoxy resin could improve the resistance to oxidative aging of the emulsion residues. In addition, it was found that the complex moduli generally increased while the phase angle decreased after PAV aging, and the aging process would lead to higher micromechanical modulus and lower adhesion. [ABSTRACT FROM AUTHOR]

Synthetic esters have long been used in a variety of applications due to their excellent thermal stability, excellent cleanliness, natural lubricity, and polarity. In the present work, we aimed to prepare some synthetic base oils through preparation of different dibasic esters by esterification of dicarboxylic acids (adipic acid and azelaic acid) with different linear alcohols (hexanol, octanol, and decanol) and branched alcohol (2‐ethyl hexanol) at 120°C. The reaction yield ranges between 85% and 94%. Fourier‐transform infrared spectroscopy (FT‐IR) and proton nuclear magnetic resonance (1H‐NMR) spectroscopy were used to analyze the structures of the produced compounds. Using thermo gravimetric analysis (TGA), the heat stability of the produced esters was determined, and it was found that the prepared esters have high thermal stability. The degradation of the prepared esters takes place in the range between 300 and 600°C. The rheological behaviour of prepared esters shows Newtonian behaviours, which means that Newtonian fluids obey viscosity Newton's law. The viscosity is independent of the shear rate. The results showed that the lubricity properties, based on their pour point, flash point, and oxidation stability of the esters, were significantly affected by the linear and branched alcohols used. There is a slight increase in kinematic viscosity and viscosity index values with decreasing the internal chain length of the dibasic acid. The esters which were based on adipic acid such as C1 exhibited maximum values of VI: 187 compared to those which were based on azelaic acid such as F1 with VI: 182. Viscosity and viscosity index increases with increasing the number of carbon atoms of the used mono‐ol alcohols. Using branched alcohols gave almost the same viscosity results compared to using linear alcohol with the same number of carbons. Almost all prepared esters give pour point results ≤ −30°C. [ABSTRACT FROM AUTHOR]

In the field of mining, one of the exploitation methods that is still the most used in rock salt, potassium, and magnesium salt deposits is the method with the room and abandoned pillar. The salt mining method with rooms and pillars represents a unique spatial system for which the establishment of an optimal correlation between the parameters of the room, pillar, and rock massif is required in any given situation. Thus, the dimensioning of the most requested element in the system is followed, and depending on its parameters, the other parameters of the system are established. Considering the exploitation method with rooms and pillars, the pillars are certainly the elements that are subjected to the greatest loads. In the situation where the deep exploitation of salt is done with square pillars, the evaluation of the optimal parameters of the elements of the exploitation system requires: establishing the loads that appear in the surrounding salt massif (the natural stress state); the qualitative-quantitative determination of the way of distribution of the secondary stress state in the pillars; evaluating the bearing capacity of the pillars; and establishing their geometric elements. Solving this problem can be achieved by different methods: based on the theory of limit equilibrium, taking into account the effective stress in the pillars; methods of the mechanics of the continuous system based on the analytical models for evaluating the secondary stress and deformation state of pillars and floors; and numerical methods combined with the results and measurements from the laboratory and in situ tests. A methodology based on the pillar–room–salt massif interaction principle was proposed for the analytically achievable stability exploitation system of rock salt by the dry method as the depth increased. Applying this method, the secondary stress-deformation state in the pillar can be established by taking into account the rheological behaviour of the salt, changing the pillar shape, and the extraction technology. The presented algorithm can be extended in the field of exploitation, where the room and pillar exploitation methods are used. [ABSTRACT FROM AUTHOR]

The filler-bitumen interaction mechanism is one of the most essential phases for comprehending the asphalt mixture's performance. However, despite numerous studies, in-depth knowledge of filler-bitumen reciprocity at a microscale level is yet to be ascertained. The goal of this research is to gain a better understanding of the filler-bitumen microscale interaction in terms of the synergy and coaction between the physicochemical and rheological performance of mastics due to filler inclusions. The rheological properties of two sustainable mastics, dolomite powder (DP) and lime kiln dust (LKD), together with a neat PEN 60/70 binder, were analysed based on a temperature sweep at elevated temperature conditions. Meanwhile, frequency sweep and multiple stress creep recovery (MSCR) tests were also conducted at pavement serviceability temperature using the dynamic shear rheometer (DSR). Physicochemical tests using a scanning electron microscope (SEM) and energy dispersive X-rays (EDX) were conducted to analyse the impact of parameters such as particle shape, grain size, texture, and chemical compositions. The DSR test results showcased how the incorporation of fillers in asphalt binder considerably improved the performance of the binder in terms of rutting and fatigue. Likewise, its strain and non-recoverable compliance parameters were substantially reduced at higher filler and binder concentrations. Physical filler attributes of low rigden voids (R.V), high fineness modulus (FM), and high specific surface area (SSA) led to greater interfacial stiffness and elasticity in LKD mastics compared to DP mastics at different loading frequencies and temperature levels. The SEM/EDX results also indicated that the elemental calcium and carbon composition of each filler component, together with its grain morphology, strongly influenced its rheological performance.

The lower content of phenolic compounds in white chocolate makes this confectionery product unhealthier and, thus, adequate for enrichment compared to other types of chocolates like dark or milk. Less phenolics in white chocolate is due to absence of dark cocoa solids, abundant in these compounds. This study aimed to develop a new product with a higher nutritional value than regular white chocolate by enriching white chocolate with blueberry juice as a natural source of polyphenols. Since phenolic compounds are highly sensitive to heat, light, oxygen, and pH, encapsulated form of blueberry juice was used to increase their stability in the product. Blueberry juice was encapsulated on maltodextrin (B/M) and added to white chocolate at 80 g/kg and 100 g/kg concentrations. Enrichment significantly (p0.05) except for the sweetness. The enriched chocolate samples were less sweet. The results of this study indicate the potential of maltodextrin as a carrier of sensitive bioactive compounds for the enrichment of products like white chocolate.

The macroscopic rheological properties of suspensions are often inextricably related to changes in their microstructure, and a number of experimental studies have demonstrated the significant influence of DLVO (Derjaguin-Landau-Verwey-Overbeek) interactions, namely microscopic repulsive and attractive forces due to surface charge on particles in suspensions, on the microstructure of suspensions, especially on cluster formation. In this study, the rheological properties of non-Brownian suspensions and their microstructures are investigated by numerical simulations combining DLVO interactions with hydrodynamics and frictional contacts. Different mechanisms have been identified to account for diverse rheological responses of repulsive and adhesive suspensions, revealing a significant association between the evolution of particle clusters and suspension rheology. In repulsive systems, competitions between repulsive and hydrodynamic forces and the resulting change in the distribution of minimum particle separation are responsible for the first shear thinning at low shear rates. Shear thickening is observed at high shear rates and is dominated by particles contacts. Enhancing attractive forces give rise to the viscosity of the suspensions while obscuring shear thickening, and particles make contacts even at the first shear thinning conditions. The second normal stress difference exhibit similar evolution with viscosity while the first normal stress difference is mainly dominated by fluctuations. Microstructure analysis shows frictional clusters appear in repulsive suspensions with growth in both quantity and size as shear rate increases. Clusters in strongly adhesive suspensions, on the other hand, break into smaller ones, resulting in a viscosity reduction. The calculation of the shape anisotropy indicates that frictional clusters in repulsive suspensions tend to expand uniformly in simulation box whereas at high attractive strength, clusters deform more cylindrical when strongly sheared. Our studies in microstructure can fundamentally help in bridging the gap between microscale evolution and macroscale rheological responses, thus contributing to the foundation of the constitutive model of non-Brownian suspensions. [ABSTRACT FROM AUTHOR]

Optimisation design of composite structures requires an accurate predictive model for forming behaviour. The simulation process contains a number of model parameters which include transverse and longitudinal viscosities of continuous fibre-reinforced viscous composites, fundamental to predicting the shear rheology. Shearing the unidirectional composite along the fibre direction gives a measure of the longitudinal viscosity (LV), whilst shearing across or transverse to the fibre direction gives a measure of the transverse viscosity (TV). Numerous experimental work was conducted in the past to measure these two viscosities for various materials. However, conflicting measurements by different test methods were obtained and these apparent discrepancies had not yet been systematically investigated in any single study. This paper reviews previous work on characterisation techniques to further understand the cause of such discrepancy, and hence to improve measurement accuracy, which would benefit future work on theoretical modelling of the composite viscosities and optimisation simulation of composites forming. Some important findings, such as effects of resin-rich areas, contributory factors of elastic effects, non-Newtonian behaviour for composites with Newtonian matrix, aspect ratio and end effects of test samples, geometry effects of fibres and fibre rearrangement during shearing, existence of a mathematical relationship between LV and TV and necessary benchmarking exercise using Newtonian matrix composites, were summarised. [ABSTRACT FROM AUTHOR]

In this paper, the relaxation behavior of polylactic acid (PLA) film in the heat-setting stage of biaxial stretching was studied. Firstly, the polylactic acid casting films were stretched synchronously in different ratios. We found that the Machine direction (MD) and Transverse direction (TD) stress relaxation curves exhibited a separation trend with the increase in the stretching ratio, and the relaxation amplitude increased gradually. Then, the stress relaxation curves were fitted by the expansion exponential equation (KWW equation). The results showed that the coefficient used to characterize the homogeneity of stress relaxation increased with the increase in the stretching ratio, and the homogeneity in Machine direction was better than that in Transverse direction. Finally, we analyzed the evolution of rheological units and the activation energy spectrum during stress relaxation. We found that the volume of rheological units gradually decreased with the increase in the stretching ratio. The activation energy spectrum exhibited a Gaussian distribution, and the symmetry axis of distribution curves shifted to the high energy. The above results would be of great significance in further understanding the deformation mechanism of polylactic acid film during biaxial stretching and providing theoretical guidance for the preparation of high-performance BOPLA films.

In the context of growing interest in plant-based food products for their potential health benefits and sustainability, this study investigates the effect of mono- and diglycerides of fatty acids application on physico-chemical properties of various plant-based cream products, compared to lecithin application in rice cream. Rheological and textural parameters, colour profile, and colloidal stability were analysed. The application of mono- and diglycerides modified the creams’ viscoelastic behaviour, showing a decrease in viscoelasticity across the samples; although in oat–coconut cream resulted in a higher viscoelasticity, indicating the formation of a gel-like structure. Rice cream with lecithin emulsifier showed lower viscoelastic properties characterised by higher phase angle (tan δ). All samples behaved as pseudoplastic materials (with a flow behaviour index n < 1). For coconut and almond creams, the consistency coefficient increased and flow behaviour index decreased after emulsifier application. Interestingly, the emulsifier addition did not significantly affect the cream’s colour profile, characterised by yellow hue angle (h*) as a dominant spectral component. The colloidal stability, indicated by a stability index (SI), was determined as well.

The lotus seed and lily bulb beverage (LLB) has a problem with solid particle sedimentation. To address this issue, LLB was homogenised twice at different pressures (0~100 MPa) using a homogeniser. This study aims to investigate the changes in the particle size distribution (PSD), microstructure, rheological behaviour, sedimentation index (IS), turbidity, physicochemical properties, and sensory quality of LLBs after homogenisation treatments. The results regarding PSD and microstructure showed that the suspended particles were decomposed at high pressure with increasing homogenisation pressure, forming small particles of cellular material, cell wall fragments, fibre fractions, and polymers. The LLB showed shear-thinning behaviour and weak gelation characteristics (G′ > G″) and rheological properties. Among all homogenisation pressures, the 60 MPa sample showed the lowest sedimentation rate and the highest turbidity. When the pressure was increased from 0 to 100 MPa, the total soluble solid (TSS) content showed an upward trend, while the ascorbic acid content (AAC) gradually decreased. The highest sensory evaluation was observed in the 60 MPa sample in terms of overall acceptability.

The use of lignin, an abundant phenolic bio-polymer, allows us to transform our fossil-based economy into a sustainable and bio-based economy. The transformation of bulk lignin into colloidal lignin particles (CLPs) with well-defined surface chemistry and morphology is a possible way to cope with the heterogeneity of lignin and use it for material applications. These CLPs can be used as emulsifiers in so-called Pickering emulsions, where solid particles stabilise the emulsion instead of environmentally harmful synthetic surfactants. This work investigates the application of CLPs produced from various bulk lignins as a stabiliser in o/w Pickering emulsions with two different oil phases (solid and liquid state). The CLPs had a primary particle size of 28 to 55 nm. They were successful in stabilising oil-in-water Pickering emulsions with high resistance to coalescence and a strong gel-like network. This enables novel applications for CLPs in the chemical and cosmetic industries, and can replace fossil-based and synthetic ingredients. [ABSTRACT FROM AUTHOR]

The rheological behaviour of dilute soil-water mixtures, such as hyperconcentrated mixtures and interstitial fluids in debris flows, can significantly affect the flow dynamics of flow-type landslides. These mixtures often contain clay, silt, and sandy particles. Despite great efforts, the effects of soil type and texture on the rheological behaviour of these mixtures are still not well understood. To tackle this issue, an experimental investigation is carried out using a narrow-gap rotational viscometer to evaluate the interactions from colloidal (clay) and non-colloidal (silt and sand) particles and possibility of flow regime change. The flow curves of dilute mixtures are determined with and without a dispersion agent. A functional curve between spindle speed and Reynolds Number or Froud Number is proposed to distinguish different flow regimes in the narrow-gap rotational viscometer. Results demonstrate the applicability of the Bingham model for describing the bulk rheological behaviour of dilute mixtures. The mixture viscosity governs the contribution of the hydrodynamic effects from all particles, while the yield stress governs the contribution of the colloidal effects from colloidal particles. Results also reveal that for dilute mixtures containing particles up to medium sand size, the main cause of the flow regime change is the flow boundary conditions. [ABSTRACT FROM AUTHOR]

Summary: The study aimed to evaluate the potential ingredient of stigma maydis (S.M.) as a hypoglycaemic functional food. In the present study, waxy corn flour and corn‐resistant starch were used to make biscuits; the influence of S.M. extracts (aqueous extract, SMA; ethanol extract, SME; mixed solvent extract, SMM) on the physical features and in vitro digestibility of biscuit were surveyed. In the meantime, the α‐amylase and α‐glucosidase inhibition of different S.M. extracts were analysed. Compared with the control dough, 5% ethanol S.M. extract (SME2) dough was observed to have the lowest storage modulus (G'), loss modulus (G"), hardness, water absorption capacity (P < 0.05), while creep strain was the highest (P < 0.05). Adding S.M. extracts could significantly reduce the L*, b* value and increase the a* value of biscuits. Besides, the S.M. extracts could decrease the glycaemic index (G.I.) of biscuits and reduce postprandial blood glucose levels. The GI of SMA1, SMA2, SME1, SME2, SMM1 and SMM2 was decreased to 62.47, 55.17, 51.46, 44.89, 53.05 and 50.11 respectively. Further, the addition of S.M. extract could show a certain inhibitory rate of α‐amylase and α‐glucosidase when added to biscuits. The inhibition ratio of 5% extract (SMA2, SME2 and SMM2) biscuit was higher than that of 1% extract (SMA1, SME1 and SMM1) biscuit (P < 0.05). As a natural functional component, S.M. extract could be a potential food supplement for type II diabetic mellitus. [ABSTRACT FROM AUTHOR]

The existence of a reducing end in the structure of maltodextrin can limit its applications as undesirable Maillard reaction would occur in some food processing steps. Consequently, a non-reducing maltoheptaose (N-G7) with a single degree of polymerisation was prepared through a cascade reaction of cyclodextrinase and maltooligosyltrehalose synthase, using β-cyclodextrin as substrate. The physicochemical properties of N-G7 were investigated. N-G7 exhibited low moisture absorption ability (8.91 and 18.02% at 43 and 81% relative humidity, respectively), excellent pH stability and thermostability (less than 10% N-G7 was hydrolysed between pH 4 and 10, even at 100°C), and a melting point higher than that of maltodextrin, as well as a typical gel-like behaviour. Most importantly, the results of Maillard reaction indicated that N-G7 was considered to be non-reducing, which suggested that it could be used in food processing where Maillard reaction should be avoided. Overall, the present work may provide important implications for the development and application of N-G7 in food products. [ABSTRACT FROM AUTHOR]

Water soluble coconut extract (WSCE) was reported as a suitable matrix for probiotic delivery as yogurt alternatives. The study aimed to evaluate the roles of brewers’ spent grain (BSG) derivatives in enhancing the properties of WSCE-based yogurt alternatives. BSG flour (BSGF) and 3 different protein extracts (BSGPs) including protein control (BSGP-C), protamex treatment (BSGP-P), and protamex combined with flavourzyme treatment (BSGP-PF) were incorporated in WSCE-based yogurt alternatives. Confocal laser scanning microscopy showed that BSGPs prepared with protease treatment generated less dense fat distribution and more homogenous globules compared to that in WSCE control yogurt. It also resulted in a softer, denser and more homogenous matrix. The modification in microstructural properties was aligned with differences in several functional groups including ⍺-glycosidic bond and hydroxyl groups from polysaccharides, aliphatic ethers and acid functional groups as well as aromatic hydrocarbons of lignin, amide I, acetyl groups and amide III. BSGF and BSGPs increased the mechanical properties, viscosity and modified flow behaviour properties demonstrating its ability in maintaining textural and gel formation. After 14 days of storage, maintenance in flow behaviour, syneresis and mechanical properties was identified. Furthermore, BSG derivatives enhanced lactic acid production up to 3 folds. In conclusion, BSG derivatives maintained the microstructure and gel formation, improved the properties of WSCE-based yogurt alternatives and preserved its behaviour during 14 days of storage.

Despite the emerging interest of biochar utilization in cement-based construction materials, there is insufficient understanding on the fresh-state performance of biochar-cement composites. In this study, various biochar samples with different characteristics were prepared as bio-based admixtures to adjust the rheo-viscoelastic properties of cement pastes, and the rheological parameters and viscoelastic evolution of the cement mixtures were comprehensively investigated. The results indicated that the type of biomass waste as biochar feedstock should be considered as the primary factor affecting its efficacy in rheological modification, owing to the distinct morphologies and water absorption capacities of biochar particles. The rheological behaviour was also tailored by different functional groups, chemical compositions, hydrophobicity, and carbon structure of the biochar. The use of 2% food waste biochar (FWBC, pyrolyzed at 500 °C) decreased the static and dynamic yield stress by 22% and 37%, enhanced the plastic viscosity by 13% and the thixotropy by 4%, and retarded the percolation by 57% and the rigidification by 31%. In contrast, the use of 2% agriculture waste biochar (AWBC, pyrolyzed at 800 °C) enhanced the static and dynamic yield stress by 252% and 187%, increased the plastic viscosity by 129% yet reduced the thixotropy by 13%, and accelerated the percolation by 124% and the rigidification by 45%. These results illustrated the important roles of different biochar in adjusting the fresh-sate performance of cementitious mixture. This study can provide theoretical support for producing self-compacting concrete and/or printable concrete with adaptive rheological behaviour towards low-carbon construction. [Display omitted] • Viscoelastic behaviour of fresh biochar-cement composites was the first time reported. • Engineered biochar was customized with desired intrinsic textural characteristics. • Biochar as bio-based admixture effectively adjusted adaptive fresh-state performance. • Food waste biochar led to a lower dynamic yield stress with a higher plastic viscosity. • Agriculture waste biochar let to a higher static yield stress with accelerated structural build-up. [ABSTRACT FROM AUTHOR]

Fibrous membranes based on natural polymers obtained by the electrospinning technique are a great choice for wound dressings. In order to promote an efficient wound repair, and to avoid antibiotics, antibacterial plant extracts can be incorporated. In the present work, the new electrospun nanofibre membranes based on monobasic phosphate curdlan (PCurd) and polyvinyl alcohol (PVA) were obtained for the first time. To establish the adequate mixing ratio for electrospinning, the behaviour of the PCurd and PVA mixture was studied by viscometry and rheology. In order to confer antimicrobial activity with the nanofibre membrane, clove essential oil (CEO) was incorporated into the electrospun solution. Well-defined and drop-free nanofibres with a diameter between 157 nm and 110 nm were obtained. The presence of CEO in the obtained nanofibres was confirmed by ATR–FTIR spectroscopy, by the phenolic and flavonoid contents, and by the antioxidant activity of the membranes. In physiological conditions, CEO was released from the membrane after 24 h. The in vivo antimicrobial tests showed a good inhibitory activity against E. coli and higher activity against S. aureus. Furthermore, the viability cell test showed the lack of cytotoxicity of the nanofibre membrane with and without CEO, confirming its potential use in wound treatment. [ABSTRACT FROM AUTHOR]

Effect of adding foxtail millet flour (FMF) (10, 20, and 30% w/w) to refined wheat flour (RWF) on physicochemical and rheological properties of dough was studied. Qualitative properties of Brotchen bread including moisture, ash, crude fibre, specific volume, and colour of the breads were evaluated. Adding FMF to the flour increased crude fibre, fat, ash, and protein contents and reduced falling number, damaged starch and wet gluten contents, and sample lightness. Consistograph test indicated that addition of the FMF decreased water absorption capacity, maximum pressure, and tolerance, however, drops in pressure at 250 and 450 s became greater. Alveograph test revealed that with adding FMF, dough resistance to extension and dough strength decreased but an increase in dough extensibility was obtained at FMF30%. Increasing the amount of FMF resulted in a decrease in the volume of the bread, and the FMB (foxtail millet bread) 30% had the highest browning index and b*. The FMB20% had the highest resilience and springiness, while higher level of foxtail (30%) increased chewiness. [ABSTRACT FROM AUTHOR]

The evolution of sustainable binders for various construction applications has resulted in the development of various geopolymer binders using various materials as aluminosilicate precursors. Geopolymer binders can be utilized as an alternative to Portland cement in the production of various materials such as mortar and concrete. In this study, geopolymer binders were synthesized using metakaolin (MK) and meta-halloysite (MH) as the aluminosilicate precursors and activated with an alkali solution having a silica modulus of 1.3 and 1.5. The resulting geopolymer binders were assessed in terms of the mechanical, permeability and durability properties. The findings from this study showed that the use of MH as the precursor resulted in better performance compared to when MK was used due to its higher reactivity and fineness. It was also found out that the use of a silica modulus of 1.5 is favourable to the hardened properties of the geopolymer binders. Geopolymer binders synthesized with MH and an activator with a silica modulus of 1.5 exhibited an increase in compressive and flexural strength of approximately 9 MPa and 1 MPa, respectively compared to when a silica modulus of 1.3 was used. Also, the corresponding porosity and water absorption is 14.5% and 10.9%, respectively lower.

The aim of this study was to evaluate the impact of high-pressure processing (HPP) on the long-term storage of chocolate fillings at room temperature, compared with conventional storage at lower temperatures. Dark chocolate fillings were treated at different pressure levels, holding times and stored at 20 °C for 12 months. Unprocessed batches were stored at 4 °C and at −12 °C. Moisture, water activity (aw), pH, colour, G′1Hz and indigenous microflora were measured at 2, 4, 6, 8, 10 and 12 months of storage. Results showed that 600 MPa/20 min processing was the most effective controlling mesophilic group, presenting 3.8 log cfu/g after 12 months of storage, and inactivating moulds and yeasts after HPP treatment. Colour was affected by storage, including a reduction in the L* parameter in all conditions to final values between 37.8 and 39.3, while the a* parameter increased during storage time at −12 °C and 4 °C to final values of around 12, and parameter b* decreased at storage temperature 20 °C to 5.3. Storage time affected the rheological behaviour of HPP-treated samples, increasing G′1Hz from the 2nd to 12th month of storage time to the final values between 1603 kPa and 2139 kPa. Moisture, aw and pH were not affected by HPP treatment nor storage time. [ABSTRACT FROM AUTHOR]

The present study aimed to develop lomefloxacin-loaded ethosomal vesicles intended to be applied topically for treating skin infections. Ethosomes were prepared using the cold method. The formulation variables were optimized using 22 factorial design and Design Expert® software for analyzing the data statistically and graphically using response surface plots. Phosphatidylcholine (X1) and ethanol (X2) were chosen as the independent variables, while the dependent variables comprised entrapment efficiency (Y1), vesicles size (Y2) and zeta potential (Y3). The optimized ethosomes were subsequently incorporated into Carbopol® 940 gel and characterized for rheological behaviour, in-vitro release, ex-vivo skin permeation and deposition. The ex-vivo permeation and skin deposition studies showed better results compared to drug solutions. In a nutshell, the ethosomal vesicles were found to be a promising carrier demonstrating enhanced topical delivery of lomefloxacin. [ABSTRACT FROM AUTHOR]

The methods for ensuring long-term and safe operation of marine equipment due to comprehensive repair technologies that use epoxy oligomers and new compositions based on them are developed. The influence of temperature and UltraSonic Treatment (UST) on the rheological properties of the pure epoxy matrix and compositions based on it is explored. The compositions have different content of nanodispersed soot carbon black of brand PowCarbon 2419G (particle size of 24 ± 2 nm). It is established that when nanoparticle soot (q = 0.10…15.00 pts wt) is introduced into the composition of the epoxy matrix treated with ultrasound, the viscosity of the composition increases gradually. Based on the results obtained, temperature ranges are recommended, in which the viscosity of the studied compositions reaches optimal technological parameters for the effective impregnation of threads, tows and various fabrics, and which provide for the effective application of the composition to the working surfaces of marine equipment. Technical recommendations are given for applying the developed black-filled epoxy compositions to the working surfaces of parts, ship mechanisms and pipeline systems of marine vessels. First published online 28 January 2021

The present work aimed at investigating an extraction protocol based on consecutive steps of isoelectric point (pH ~ 4.25) mediated gum swelling and deproteinisation as an alternative method to produce flaxseed gum extracts of enhanced techno-functional characteristics. The osidic and proximate composition, structure conformation, flow behaviour, dynamic rheological and thermal properties of gums isolated from brown and golden flaxseeds were assessed. Gum extraction under near-to-isoelectric point conditions did not impair the extraction yield, residual protein and ash content, whilst it resulted in minor changes in the sugar composition of the flaxseed gum extracts. The deconvolution of the GPC/SEC chromatographs revealed the presence of four major polysaccharidic populations corresponding to arabinoxylans, rhamnogalacturonan–I and two AX-RG-I composite fractions. The latter appeared to minimise the intra- and interchain polymer non-covalent interactions (hydrogen bonding) leading to a better solvation affinity in water and lyotropic solvents. Golden flaxseed gums exerted higher molecular weight (M w = 1.34–1.15 × 106 Da) and intrinsic viscosities (6.63–5.13 dL g−1) as well as better thickening and viscoelastic performance than the brown flaxseed gum exemplars. Golden flaxseed gums exhibited a better thermal stability compared to the brown flaxseed counterparts and therefore, they are suitable for product applications involving severe heat treatments. • The mixed effects of phenotype and pH-mediated extraction on flaxseed gum properties were studied. • Gum extracts comprised four major fractions i.e., arabinoxylans, rhamnogalacturonan-I and their composite exemplars. • Flaxseed phenotype affected substantially the flow and dynamic rheological behaviour of the gum solutions. • Gum extraction at pH ≈ pI reduced the k H , hydrodynamic diameter and net charge of the gum solutions. • pH-mediated extraction did not alter the proximate and sugar composition of the gums. [ABSTRACT FROM AUTHOR]

The type of aluminosilicate precursor used in the synthesis of geopolymer binders plays a huge role in the resulting performance. Thus, it is critical to understand the properties of precursors and how they influence the corresponding performance of geopolymer binders. In this study, metakaolin and meta halloysite are used as the aluminosilicate precursor in the synthesis of geopolymer binders. These precursors are obtained locally in order to propel the sustainable development and application of geopolymers. The precursors were characterized and the corresponding influence on the reactivity, rheology and setting times of geopolymers was investigated. In addition to the influence of precursor type on the properties of the geopolymers, the effect of two silica moduli (i.e. 1.3 and 1.5) was also evaluated. The results from this study indicated that increasing the activator silica modulus from 1.3 to 1.5 extended the setting times and increased the stress strain of the geopolymer binders. Characterization of the precursors indicated that metakaolin has a higher amorphous content compared to that of meta halloysite. However, the finer particles of meta halloysite embodied it with the ability to participate in a faster geopolymerization and result in more formation of activation products.

In this study Ginkgo biloba leaf extract which is rich in phytochemical metabolites was used as a pectin substitute in quince jam. The extraction process was performed ultrasonically at 70°C with ethanol that gives the highest flavonoid content. The jam was produced with pectin in the traditional procedure and pectinfree jams were made using two different weight concentrations (0.05% and 0.1%) of Ginkgo biloba extract and compared to the pectin group. Shear stress value decreased when Ginkgo biloba was used as a pectin substitute so the jam becomes softer. Phenolic content 170.09 (mg/g GAE), and antioxidant activity (1.80 mM Trolox/100g) was found highest in the 0.1 g extract group. Lightness and yellowness increased with Ginkgo biloba compared to the pectin group. The jam sample with 0.1 g extract was preferred in sensory tests. [ABSTRACT FROM AUTHOR]

This investigation centers on the synthesis of a polysaccharide-protein blend produced by an isolated native strain (99.12 % phylogenetic affinity with Bacillus arachidis SY8(T)). The primary objective was to investigate the production of extracellular polymeric substances (EPS) under diverse stress conditions, encompassing exposure to heavy metal ions, salt, and toxic agents. Additionally, the impact of environmental parameters, namely pH, inoculation percentage, and time, on the production was investigated. Subsequently, the study examined the biosorption potential of the EPS produced for Pb(II), Cu(II), and Mn(II). The EPS obtained was thoroughly characterized via various tests. Rheological evaluations of an EPS solution (2 wt%) confirmed its pseudo-plastic and non-Newtonian fluid properties, while TGA analysis demonstrated its thermal stability up to 600 °C. Additional analyses, including GPC, FTIR, and H-NMR, provide further insights into the produced EPS. The best conditions for EPS production are determined: 5 % NaCl salt, serving as an effective stress inducer, and 37 °C, pH 6, with a 5 % inoculation, over 96 h. EPS demonstrates remarkable removal efficiencies of 99.9, 99.4 and 78.9 % for Pb(II), Cu(II), and Mn(II), respectively. These findings highlight the potential of EPS as an effective agent for removing heavy metal ions. [Display omitted] • Biosynthesis of EPS by B. arachidics (isolated from soil) was performed. • EPS production was increased from 1.8 to 7.8 g/l in the presence of 5 % NaCl. • Conditional factors played a pivotal role in influencing EPS production. • In-depth EPS characterization provides comprehensive insights into its properties. • Significant heavy metal removal (e.g. 99.43 % for Cu(II)) demonstrated EPS efficacy. [ABSTRACT FROM AUTHOR]

Due to the increase in reserves and production of heavy crude oil in Colombia´s Llanos basin, and the decline of production of light conventional crude oil used traditionally as diluents, and as result of a comprehensive technical - economic evaluation, ECOPETROL S.A decided to implement a scheme of heavy oil transport by pipeline, using naphtha as diluent. By using the basic equation of flow of fluids, a methodology to estimate the maximum flow rate of transport of a particular pipeline for a specific fluid was developed. This tool was used to determine the flow regime in which the Castilla viscous crude oil can flow in laminar regime under the same conditions of pressure drop and flow rate than a low viscosity fluid flowing in turbulent flow. This way, the naphtha requirement was minimized. By using this algorithm, based in the explicit equation of Churchill and Usagi for the estimation of friction coefficient, the optimum viscosity for the Castilla oil ¿ naphtha blend was found to be close to 300 cSt at 30°C for the Apiay - Porvenir pipeline, the mail bottleneck in Ecopetrol pipeline infrastructure for the evacuation of heavy oil from Colombia´s Llanos basin. The evaluation also included the development and implementation of scheme of segregation of heavy and light crude oil. The opportune implementation of the segregated scheme of handling and transport of Castilla crude oil diluted with naphtha ECOPETROL was able to increase Castilla crude oil production from 40 to 75 thousand barrels of oil per day (KBPD) in a 5 year span. The exports of ¿Castilla blend¿ average 2.5 million barrels per month during 2008, becoming Colombia´s main exportation product.

Poly (3-hydroxybutyrate) (PHB) is a biodégradable polymer which its application in industrial was limited due to sensitive to high processing temperature and poor mechanical properties. The thermal and rheological behavior for blends of PHB extracted from dry weight of Jatropha and Poly (ethylene glycol) (PEG) were investigated. Blends of PHB/PEG (PHB 100, PHB 80, PHB 60 and PHB 50) have been prepared through solution blending method. The thermal using Differential Scanning Calorimetry (DSC) and Thermogravimetric Analysis (TGA) and rheological behavior using Oscillating Disk Rheometer have been investigated. The results indicate all PHb/PEG blends showed decreased at lowest melting temperature crystallinity (Xc). The TGA result showed that PHB 80 less degraded and suggest better thermal stability compared to PHB 60 and PHB 50. Adding PEG to PHB also improved the rheological behavior of PHB. At higher frequency range, PHB 100 showed less dependency on frequency indicating the elastic structure it has compared to PHB 80, PHB 60 and PHB 50.

The energy demand for space cooling has more than tripled for the past thirty years and was responsible for emissions of about 1 Gt CO2 annually. The ever-increasing energy demand for cooling has posed a demanding question on improving the energy efficiency of cooling processes. On the other hand, with the growing global demand on LNG, cold energy released from LNG terminals has been growing to a historical high at 6.6 × 1014 kJ in 2017. Thus, there is a strong need to search for a suitable phase change material (PCM) best utilizing the cold energy released from the production sectors for storage and transport to the needed sectors. Among all the PCMs, semiclathrate hydrates (SCHs) with a suitable phase change temperature (5–27 °C) and high latent heat (190–220 kJ/kg) stand out as one promising candidate (a) to store and transport the cold energy and (b) to improve the energy efficiency of the cooling processes synergistically. In this review, we focus on reviewing SCHs as a cold energy storage and transport PCM covering both its fundamental properties (thermophysical properties, kinetics of formation and dissociation, rheological and transport properties, and safety and economic aspects) and its novel applications in several cooling processes. Prospects and challenges are also delineated on commercializing SCHs as a key technology enabler for the cold energy industry. There is strong confidence that possible disruptive SCH-based cooling technologies could be developed in the near future for energy efficiency improvement and environmental sustainability.

To be used as a new kind of three-dimensional printing material, rheological behaviour of a La-based bulk metallic glass (BMG) was studied over a wide range of high temperatures and strain rates by uniaxial compression experiments. The variations in peak stress and steady stress with temperature and strain rate were analysed. Three rheological regions were revealed for the BMG: a non-Newtonian, a Newtonian and an abnormal region which are determined by the temperature and strain rate. The variation on viscosity further indicates that the rheological mode transforms from Newtonian fluid to non-Newtonian fluid with the increase of strain rates at the same temperature. The results from scanning electron microscope test also confirm the microstructural changes that occurred at three different rheological modes. The crystallisation kinetics of La55Al25Ni5Cu10Co5 was studied by thermal analysis and the result show that the crystallisation process of La55Al25Ni5Cu10Co5 glassy alloy is the diffusioncontrolled growth. The relationship among steady-state stress, strain rates and temperatures are determined by using hyperbolic function under high-temperature compression test. The curve shows that the logarithmic relationship between the steady-state stress and strain rates satisfies the linear relationship. Besides, the activation energy Q of this amorphous alloy in Newtonian rheological region is 131.31 kJ/mol. [ABSTRACT FROM AUTHOR]

Unreasonable choice of solid content (SC) and cement-to-tailings ratio (c/t), including pipeline networking system, will lead to some pipeline problems, such as blockage, wear, and rupture. Hence, this study deals with the rheology and sedimentation characteristics of fresh CTB slurry. Samples having a SC value of 65, 67 and 69wt.%, as well as a c/t ratio of 1:2, 1:1 and 1:4, were prepared and exposed to their rheological tests. Likewise, the sedimentation properties of CTB slurry was studied by picking polyacrylamide (PAM) as flocculant. Results showed that: (1) CTB's slump reduced with growing SC and c/t values when SC was kept constant. (2) The viscosity and shear stress increased with increasing SC values, signifying a linear link between shear stress and stress rate. (3) There was also an exponential link between sedimentation rate and PAM flocculant content in CTB. When PAM value increased from 75 to 80 g/t, a clear difference was observed in the clarification layer height (CLH). The CLH increments were also 7.5 and 7.14% for a ST of 20 and 30 min, respectively. Finally, this work will greatly contribute to the mining industry in assessing the transport aspect of CTB slurry to underground mined-out stopes. [ABSTRACT FROM AUTHOR]

Summary: Yogurt preserves and enhances nutritional value of milk. In this study, we have compared several strains to determine the physicochemical, sensory, rheological and aroma characteristics of different yogurts. We used Lactobacillus gasseri LGZ 1029 (LG), commercial probiotic L. rhamnosus (LGG) and traditional fermentation strains Streptococcus thermophilus and L. bulgaricus (SL). Results showed that the flavour and texture characteristics of mixed‐strain yogurts were obviously better than in single‐strain yogurts. Addition of LG increased pseudoplastic behaviour, as shown by Herschel–Bulkley model analysis of rheological behaviour. The LG + SL group also had both the highest viscosity consistency index and thickening ability. In addition, a total of 57 volatile compounds were detected in yogurts and the fermentation with the addition of LG was mainly affected by ketones. Our study suggested that a yogurt with new attributes can be produced by using LGZ 1029. [ABSTRACT FROM AUTHOR]

Summary: The stability of aqueous purified tara gum (TG) mixtures with sodium caseinate (NaCas) and whey protein concentrate (WPC) was investigated. Phase diagram of TG–milk proteins mixtures was obtained by measuring the sedimented fraction or the rheological parameters. The rheological behaviour was also evaluated as function of NaCas and WPC concentration, considering the zero‐shear rate viscosity and the relaxation time as response variables. The rheological parameters were determined by rotational rheometry. The studied solutions presented a meta‐stable condition provided by the increase in viscosity, while mixtures with NaCas at low TG concentrations sedimentation by volume exclusion occurred. The rheological behaviour of NaCas and WPC aqueous solutions approached the Newtonian and shear‐thickening model, respectively. The mixtures with TG showed a pseudoplastic behaviour, approaching the Cross model. The results indicated interaction between TG and the studied proteins, expressed by an increase of zero‐shear viscosity and the relaxation time at higher gum concentration. [ABSTRACT FROM AUTHOR]

Fibrous membranes based on natural polymers obtained by the electrospinning technique are a great choice for wound dressings. In order to promote an efficient wound repair, and to avoid antibiotics, antibacterial plant extracts can be incorporated. In the present work, the new electrospun nanofibre membranes based on monobasic phosphate curdlan (PCurd) and polyvinyl alcohol (PVA) were obtained for the first time. To establish the adequate mixing ratio for electrospinning, the behaviour of the PCurd and PVA mixture was studied by viscometry and rheology. In order to confer antimicrobial activity with the nanofibre membrane, clove essential oil (CEO) was incorporated into the electrospun solution. Well-defined and drop-free nanofibres with a diameter between 157 nm and 110 nm were obtained. The presence of CEO in the obtained nanofibres was confirmed by ATR–FTIR spectroscopy, by the phenolic and flavonoid contents, and by the antioxidant activity of the membranes. In physiological conditions, CEO was released from the membrane after 24 h. The in vivo antimicrobial tests showed a good inhibitory activity against E. coli and higher activity against S. aureus. Furthermore, the viability cell test showed the lack of cytotoxicity of the nanofibre membrane with and without CEO, confirming its potential use in wound treatment.