Rheological Evaluation Research Articles

Statistical and rheological evaluation of the effect of salts in partially hydrolyzed polyacrylamide solutions

AbstractPartially hydrolyzed polyacrylamide (PHPA) is the most common anionic copolymer used in Enhanced oil recovery (EOR), but the use of this polymer presents some limitations in the presence of divalent cations. The objective of this work was to evaluate the thermal stability of PHPA in brines containing Na+, Mg2+, and Ca2+ cations (isolated or combined). In this study, the PHPA used at a concentration of 2500 mgL−1 has a MW of 20 × 106 Da. The stability of the polymeric solutions was monitored through rheological analyses for 180 days at 70°C, in the absence of oxygen, using a central composite rotational design. In the absence of dissolved oxygen and cations, the PHPA solution was basically the same as that observed over a period of 30 days. It was observed that Ca+2 ion had the greatest influence on reducing the viscosity of PHPA in all cases. Polymeric solutions with Total dissolved solids (TDS) greater than 1000 mg L−1 showed complete degradation of the polymer in 180 days. The statistical data corroborate the rheological results, showing that only the main effect of Na+ was not statistically significant and that the concentrations of Mg2+ and Ca2+ presented statistically significant effects in their linear components and quadratic components.

Dynamic-Mechanic Analysis and Rheological Modelling of Waste Face Mask Modified Bitumen

Due to the Covid-19 global pandemic, the use of face masks has increased considerably in recent years. Used face masks are released into our environment and become a severe environmental threat. Therefore, researchers have focused on the recycling of waste face masks. Recently, studies have been carried out on the use of waste face masks as additives in bituminous materials, but a detailed rheological characterization has not been made. In this study, modified bitumens were obtained by adding 1%, 1.5%, 2%, 2.5%, and 3% waste face mask (WFM). Subsequently, frequency sweep test was performed on modified bitumen samples through a Dynamic Shear Rheometer (DSR). Thus, the viscoelastic behavior of WFM modified bitumen was investigated at different temperatures and loading rates. Performance analysis was conducted with rheological master curves, which were characterized according to analytical and mechanistic models. In this study, rheological evaluations were performed according to the Christensen-Anderson (CA) Model, Christensen-Anderson-Marasteanu (CAM) Model, Sigmoidal Model (SM), and finally, the mechanistic Huet-Sayegh Model (HSM). According to the results, it was determined that WFM significantly increased the rutting resistance of bitumen and performed better at low and high loading rates than the pure bitumen at each WFM ratio.

Otimização das propriedades reológicas das massas de pães com substituição de farinha de trigo por farinhas de grão inteiro de pseudocereais Andinos germinados

ABSTRACT: This study optimized the rheological parameters of doughs with partial substitution of wheat flour for blends of whole grain flours from germinated Andean pseudocereals such as quinoa (GQF), kiwicha (GKF), and cañihua (GCF) for bread production. The optimization was conducted through a Simplex-Centroid Mixture Design (SCMD) and Desirability Function (DF). Experiments were formulated using 80 to 90% wheat flour and 5 to 15% germinated pseudocereal blends. The rheological evaluation included farinograph, extensograph, and amylography analyses. Results showed that whole flour from germinated pseudocereals increases the water absorption, consistency, and extensibility of the doughs; and decreases its development time, stability, resistance to extensibility, temperature, and peak viscosity. The GQF-GKF blend developed more extensible and stable doughs, while GCF increased its consistency and was recommended for bread production. The data allowed us to obtain response surface models and the optimal substitution percentages to produce bread using GQF-GKF, GQF-GCF, and GKF-GCF blends.

Dough rheology and internal structure of bread produced with wheat flour partially substituted by buckwheat flour: A step towards enhancing nutritional value

Buckwheat flour is a pseudocereal that can be used to improve the nutritional value of staple food, such as bread. However, substituting wheat flour can be challenging due to potential loss of the final product's technological quality. Therefore, understanding the influence of buckwheat inclusion level on dough rheology and bread quality is essential. This study evaluated the effect of wheat flour substituted by buckwheat flour on dough rheology and bread quality over the staling process. Wheat flour was replaced by 0%, 10%, 20% and 30% of buckwheat flour and the resulting dough mixing properties, viscosity profile, gel texture, rheology behaviour and extensibility properties were analysed. Internal bread structure (C-Cell and confocal microscopy), specific volume, density and crumb texture profile were also assessed. The increase in buckwheat level gradually decreased flour water absorption (p < 0.05), dough stability and development time, with increased gluten weakening as evidenced by decreased C2 values (protein strength) of Mixolab. As a result, the dough was less resistant to extension, with decreased extensibility. The highest viscosity profile of the starch paste was observed with 30% buckwheat inclusion level, which may lead to faster bread staling process. A solid-like and elastic behaviour was observed in the rheology evaluation, suggesting an interaction between fibre and starch from buckwheat with gluten proteins. Although changes in dough rheology occurred, the bread quality remained unchanged at levels of up to 20% buckwheat level (p > 0.05), with similar specific volume, density, internal structure and texture profile compared to the control bread (0% buckwheat). In conclusion, buckwheat was found to be a viable wheat flour substitute with only minimal changes in dough behaviour and maintenance of bread technological quality, while enhancing the nutritional profile by increasing fibre content and total essential amino acid.

3D-printed Chlorella vulgaris biocarriers: A novel approach to wastewater treatment

Recently, the use of microalgae in 3D printing has been investigated. It has great potential for use in a wide variety of environmental fields such as wastewater treatment. Microalga Chlorella vulgaris biocarriers were fabricated using 3D printing, and their applicability in wastewater treatment was evaluated. To select a candidate hydrogel to support C. vulgaris, alginate (Alg)/methylcellulose (MC) hydrogels containing 3 % Alg and 2, 5, and 8 % MC were used. Based on the rheological evaluation, the Alg3/MC8 hydrogel containing 3 % Alg and 8 % MC showed gel-like behavior. Moreover, it did not degrade compared to Alg3/MC2 and Alg3/MC5. The microalgal ink Alg3/MC8w/, which is C. vulgaris-laden Alg3/MC8 hydrogel, showed the best printability in the shape fidelity and stackability tests. It could also be stacked into a structure with 30 layers (10.5 mm) at 98 ± 2.3 % accuracy compared to the 3D model. In addition, it achieved removal efficiencies of 52 ± 6 % and 88 ± 6 % for soluble nitrogen and phosphorus, respectively, confirming that it could be applied in wastewater treatment. The results demonstrated that the enhancement of various wastewater treatment procedures can be achieved using 3D-printed microbial biocarriers that offer control over targeted microorganisms.

Effect of adding sodium caseinate, whey protein concentrateand milk protein concentrate on the physical, rheological and sensory properties of yogurt produced from goat milk

Yogurt is a widespread fermented dairy product widely consumed worldwide. The present study aimed to examine the impact on the yogurt's made from goat milk's physicochemical, rheological, and sensory aspects by incorporating varying percentages of Sodium Caseinate (SC), whey protein concentrate (WPC), and cow milk protein concentrate (MPC) during production to produce good quality yogurt. Four different treatments weremade and assigned as control treatment C, treatment C1 (SC was added at a percentage of 1% and 2%), treatment C2 (WPC added at a percentage of 1% and 2%), and treatment C3 (MPC added at a percentage of 1% and 2%). Estimates of pH and total acidity were among the physiochemical tests performed. Rheological evaluations includedviscosity, the ability to separate whey spontaneously, and moisture retention. Texture tests included hardness, springiness, and cohesiveness. A sensory evaluation of the produced yogurt was also done. The results showed an approximation in the additional treatments' total acidity and pH ​​values immediately after manufacturing. Compared to the control treatment, the additional treatments decreased the values of spontaneous whey separation and increased the water holding capacity and viscosity. However, the product's texture was enhanced due to the addition of the three protein components, which contributed to its hardness, springiness, and cohesion. There was an improvement in the sensory properties of the addition treatments compared to the control treatment and directly related to the increment in the addition percentage.The yogurt resulting from the addition of (SC, WPC, and MPC) led to the production of good-quality yogurt.

Rheological and sensorial evaluation of fruit nectar with chia mucilage

Chia mucilage is exuded from chia seed (Salvia hispanica) when dispersed in water. It can be used as an ingredient rich in fiber to improve the nutritional and kinetic stability of food and beverages. The effect of chia mucilage concentration on the physicochemical, rheological, and sensory properties of passion fruit nectar was evaluated. Chia mucilage was extracted and added to passion fruit nectar in different concentrations (0, 0.1, 0.2, 0.4, 0.6, and 0.8% w/w). The color, phase separation, rheology on steady state at 10 °C and 25 °C, and sensorial acceptance and descriptive tests were performed on passion fruit nectars with chia mucilage. Lower phase separation of nectar was observed with mucilage concentration increase, which was associated with rheological behavior. The mucilage use leads to nectars with increased viscosity and yield stress, reflecting the formation of a more resistant network structure with chia mucilage. However, the increase in viscosity reduced the texture acceptance scores by consumers when 0.4% or more of chia mucilage was used. The use of 0.1% and 0.2% mucilage preserved the acceptance scores and sensory properties of fruit nectar, such as fruit flavor and aroma, sweet taste, homogeneity, and shine. On the other hand, the use of 0.8% mucilage caused greater intensity of negative attributes on nectar, such as strange taste, strange flavor, viscous, cloudy, and particulate. In this way, chia mucilage can be used in different concentrations to improve stability and achieve desirable rheological, and sensory characteristics and healthy benefits according to the priority demand of consumers.

An injectable gel based on photo-cross-linkable hyaluronic acid and mesoporous bioactive glass nanoparticles for periodontitis treatment

Guided bone regeneration (GBR) is an effective strategy to promote periodontal tissue repair. The current study aimed to develop an injectable gel for GBR, composed of photo-cross-linkable hyaluronic acid and mesoporous bioactive glass nanoparticles (MBGNs) loaded with antibacterial minocycline hydrochloride (MNCl). Hyaluronic acid modified with methacrylic anhydride (MHA) that could be cross-linked under UV irradiation was first synthesized. Dynamic rheological evaluation of MHA under UV was carried out to determine its in-situ gelling feasibility and stability. Morphological and mechanical characterization was performed to determine the optimal concentration of MHA gels. Sol-gel derived MBGNs loaded with MNCl were further incorporated into MHA gels to obtain the injectable drug-loaded MBGN-MNCl/MHA gels. In vitro antibacterial, anti-inflammatory and osteogenic effects of this gel were evaluated. It was shown that the MHA gel obtained from 3 % MHA under UV treatment of 30s exhibited a suitable porous structure with a compressive strength of 100 kPa. MBGNs with particle size of ∼120 nm and mesopores were confirmed by TEM and SEM. MBGNs had a loading capacity of ∼120 mg/g for MNCl, exhibiting a sustained release behavior. The MBGN-MNCl/MHA gel was shown to effectively inhibit the proliferation of Streptococcus mutans and the expression of pro-inflammatory factors IL-6 and TNF-α by macrophages. It could on the other hand significantly promote the expression of osteogenic-related genes ALP, Runx2, OPN, and osterix of MC3T3-E1 cells. In conclusion, the current design using photo-crosslinkable MHA gel embedded with MNCl loaded MBGNs can serve as a promising injectable formulation for GBR treatment of irregular periodontal defects.

Evaluation of Rheological and Microscopic Properties of SBS-Modified Asphalt Binder with Multiple Regeneration

Evaluation of Rheological and Microscopic Properties of SBS-Modified Asphalt Binder with Multiple Regeneration

Development and Evaluation of Polyherbal Formulation with Carminative Effect

Carminative drugs, which reduce or prevent gastrointestinal flatulence and colic and have historically been used to enhance human health, is examined in this study. The carminative qualities of spices like clove, coriander, cardamom, fennel, nutmeg, black pepper, and ajowan are highlighted in particular. Numerous health benefits, including anti-inflammatory, antiseptic, anti-hypertensive, and myorelaxant qualities, are demonstrated by these spices. To enhance their effects, formulations were made utilizing a geometrical approach and different weights of these powders were combined and evaluated. To confirm the quality and safety of the carminative powder, organoleptic evaluation, physicochemical characteristics, rheological evaluation, and carminative potential were evaluated. The carminative powder, had a pH of 6.5, is free-flowing, non-sticky, and aesthetically pleasing, according to the results. Given the rising popularity of natural treatments and holistic healthcare, the future of carminative herbal medications is bright. Due to their digestive advantages, many herbs and mixtures have grown in popularity, and this pattern is predicted to continue. New carminative herbs and novel formulations may be found as a result of research and development in herbal medicine in the upcoming years. The market for carminative herbal medicines is projected to grow as consumer interest in plant-based treatments for digestive problems rises.

Development of a “Green” Emulsion with a Milk Protein Hydrolysate: An Evaluation of Rheology, Texture, In Vitro Bioactivity, and Safety

Bioactive peptides are promising cosmetic active ingredients that can improve skin health and appearance. They exhibit a broad spectrum of activity, including anti-aging, antioxidant, antimicrobial, and anti-inflammatory effects. The aim of this study was to develop a safe, stable, and efficacious environmentally friendly (“green”) emulsion using a milk protein hydrolysate as a model active ingredient. Potential emulsions were formulated with biodegradable emollients, stabilized with naturally derived mixed emulsifier, and prepared by cold process. They were evaluated for rheological behavior (continuous rotation and oscillation tests), physical stability (dynamic mechanical thermal analysis—DMTA test), and texture profiles, as well as cytotoxic, antioxidant, and antimicrobial effects. Rheological characterization revealed shear-thinning flow behavior with yield point from continuous rotation tests and predominantly elastic character from oscillation (amplitude and frequency sweep) tests, with small structural change detected in the DMTA test. These results implied satisfactory rheological properties and good stability. Texture analysis revealed acceptable spreadability and substantivity of the emulsions. The protein hydrolysate showed antioxidant activity. The developed emulsions showed low antibacterial activity against selected microorganisms, but this was due to the action of preservatives, not peptides. All potential emulsions showed a desirable safety profile. The results obtained provide the basis for the next stage of formulation development, i.e., in vivo efficacy tests.

The feasibility of marine oleogel based on fish oil canning industry by‐products, structured with beeswax and rice bran wax

SummaryThe presence of trans fatty acid in food is often reduced through the use of fat replacers or oleogel technology. However, these alternatives typically encounter a scarcity of resources, specifically vegetable oil, which serves as the primary raw material. In fact, oil derived from marine, particularly fish oil by‐products, can be valorised as a colloidal architecture. Therefore, this study aims to assess the optimal type of oleogelator by applying different concentrations of beeswax (BW) and rice bran wax (RBW) in the generating of oleogel based on fish oil by‐product. Oleogel thermogram showed a shift in the melting point with increasing temperatures for concentrations of 5%, 10% and 15%. Oleogel containing 15% BW and 5% BW had the highest (99.27 ± 0.55%) and lowest (78.20 ± 2.54%) oil binding capacity, respectively. The rheology evaluation showed dynamic shifts in oleogel system as the type and concentration of oleogelator were altered, underscoring the importance of G′ and G″. The use of a 10% oleogelator generated preferable results for both BW and RBW in terms of melting point, OBC, viscous behaviour and appearance of oleogel. Furthermore, this selected oleogel strategy exhibited similar textural properties to commercial margarine when used in a sponge cake as the food model system.

Comb polymer/layered double hydroxide (LDH) composite as an ultrahigh temperature filtration reducer for water-based drilling fluids

In deep-formation drilling, effective filter loss control in ultrahigh-temperature conditions and high-salt conditions faces challenges. Comb polymer/LDH composites (P-LDH) with partially intercalated and partially exfoliated structures were prepared by in-situ polymerization as fluid loss materials. A series of characterization results showed that the P-LDH composites were successfully synthesized. P-LDH had partially intercalated and partially exfoliated structures and excellent thermal stability. In addition, the rheological evaluation results showed that P-LDH had a low viscosity effect while maintaining the rheological properties of the drilling fluid. P-LDH can significantly reduce the filtrate loss of drilling fluids at ultrahigh temperatures and high salt concentrations. At 240 °C and 15 wt% NaCl, the filtration loss was only 6.3 mL, and the high-temperature and high-pressure filtration loss was only 29.6 mL. Through the analysis of drilling fluid particle size and filter cake microstructure, based on hydrogen, ionic bonds, and intercalation effects, P-LDH acted closely with bentonite to promote stable dispersion, improve the drilling fluid’s stability, and form a dense filter cake to reduce the filtration loss. Therefore, P-LDH has broad application prospects in ultrahigh-temperature and high-salinity formation drilling.

Quality Characteristics of Purslane (Portulaca oleracea L.) Leaf and Stem Powder-Supplemented Cupcakes

The current research focused on improving the nutritional quality of cupcakes by using micronutrient-rich vegetables, specifically purslane’s leaves and stems. The purslane leaves and stems were sun-dried and analyzed for their proximate, mineral, and antioxidant potential. After conducting preliminary trials, flour blends supplemented with purslane powders ranging from 2 to 4% were evaluated for their rheological behavior and suitability in bakery cupcakes. The results indicated that purslane leaves and stems are a rich source of crude proteins (18.04 ± 0.61 and 15.62 ± 1.63%, respectively) and mineral contents, especially iron contents (214.28 ± 123.13 and 243.37 ± 5.25 mg/100 g, respectively). The powder retained a significant quantity of phenolic compounds and antioxidant potential after sun-drying. The rheological evaluation indicated the dose-dependent incremental response on dough development and dough stability time. Although cupcakes prepared with purslane leaves and stem powder received lower ratings than the control, statistically, the cupcakes supplemented with 2 to 4% purslane powder were on par with each other. In conclusion, purslane leaves and stems are a rich source of micronutrients and their incorporation in bakery products can improve the consumer’s micronutrient intake.

Modification effects of nanosilica on asphalt binders: A review

Abstract Nanosilica (NS) may be obtained as a by-product in several industrial processes and is associated with high availability and affordability among other nanoadditives. NS has been used for asphalt modification, and improvement in high-temperature performance and several other physical properties has been reported. However, due to the wide varieties and intrinsic variability of asphalt materials, concerns have been raised about the reproducibility of some conclusions, and therefore, a review was conducted. According to the results, NS additives with a purity of over 99% were usually used for modification and the specific surface area was over 100 m2/g, leading to the superior absorption of asphalt and thus improvement in rutting resistance of the mixtures. Due to a lack of guidance for the blending procedures, inconsistency exists among studies in the shear speed, blending duration, and temperature, leading to possible excessive blending and unnecessary energy and time consumption. Rises in NS concentration would cause higher softening point and rotational viscosity, and therefore elevated temperatures for mixing and paving, but penetration would be reduced. According to rheological evaluations, with the rise of NS concentration, the rutting parameter would increase, indicating an improvement in the high-temperature performance, but the low-temperature performance may deteriorate.

Rheological Evaluation and Life Cycle Cost Analysis of the Geopolymer Produced from Waste Ferrochrome Electric Arc Furnace Fume as a Composite Component in Bitumen Modification

Rheological Evaluation and Life Cycle Cost Analysis of the Geopolymer Produced from Waste Ferrochrome Electric Arc Furnace Fume as a Composite Component in Bitumen Modification

Impact of high shear blending on distribution of magnesium stearate on lactose for dry powder inhaled formulations

The use of magnesium stearate along with lactose in Dry Powder Inhaler (DPI) formulations is increasing.The impact of different conditions of high shear blending on the distribution of magnesium stearate on lactose particles was investigated in this study. The formulated blends were manufactured using high shear blending of pre-blended coarse and fine lactose particles with 1.0% (w/w) magnesium stearate under different blending conditions, specifically blending speed and time. The effects of blending conditions on the distribution of magnesium stearate on lactose particles were clearly identifiable by characterizing the formulated blends by means of rheological evaluations, scanning electron microscopy, and chemical surface analysis using time-of-flight secondary ion mass spectrometry (ToF-SIMS). Rheological properties were significantly affected in blends with magnesium stearate compared to blends without magnesium stearate. Blending speed exhibited a strong influence on the distribution of magnesium stearate on lactose surface, while blending time had relatively minor effect.

Medical-Grade PLA Nanocomposites with Optimized Tungsten Carbide Nanofiller Content in MEX Additive Manufacturing: A Rheological, Morphological, and Thermomechanical Evaluation.

The goal of this paper is to investigate tungsten carbide (WC) as a reinforcement in the popular material extrusion (MEX) additive manufacturing (AM) procedure. The impressive characteristics of WC demonstrate its potential as a valuable additive for commonly used polymeric matrices in MEX 3D printing, offering reinforcement and stabilization properties. The mechanical properties of hybrid polymer/ceramic nanocomposites made up of various filler loadings (0-10 wt. %) of medical-grade polylactic acid (PLA) and WC were studied. The mechanical characteristics, structure, and thermomechanical properties of the resulting compounds were fully characterized following the respective standards. The fracture mechanisms were revealed with Scanning Electron Microscopy. Overall, a laborious effort was implemented with fifteen different tests to fully characterize the nanocomposites prepared. In comparison to the raw PLA material, the tensile strength of the 4.0 wt. % WC PLA/WC nanocomposite was improved by 42.5% and the flexural strength by 41.9%. In the microhardness test, a 120.4% improvement was achieved, justifying the properties of WC ceramic. According to these findings, PLA nanocomposites reach high-performance polymer specifications, expanding their potential use, especially in wear-related applications.

Effects of Continuous and Cycled Annealing on the Physicochemical Properties and Digestibility of Water Caltrop Starch.

The effects of treatment time of continuous annealing (ANN) and cycle numbers of cycled ANN on the structural, physicochemical, and digestive properties of water caltrop starch were studied under 70% moisture at 65 °C. It was found that continuous and cycled ANN have no significant effects on the morphology of starch granules. However, the relative crystallinity and content of resistant starch increased pronouncedly, possibly due to crystalline perfection, which also led to the rise in gelatinization temperature and the narrowed gelatinization temperature range of starch. The treatment time in continuous ANN generally showed a pronounced effect on the rheological properties of water caltrop starch. During pasting, the breakdown viscosity and setback viscosity of all treatment decreased, implying that ANN modified starch was less susceptible to the condition in heating and continuous shearing, and less likely to cause short-term retrogradation. In contrast, peak viscosity decreased with increasing treatment time of continuous ANN, indicating crystalline perfection restricted the swelling of starch granules and viscosity development during pasting process, which was consistent with the results of steady and dynamic rheological evaluation. All ANN-modified samples showed pseudoplastic behavior with weak gel viscoelastic characteristic. Under a total annealing time of 96 h, the pasting and rheological properties of water caltrop starch were essentially less affected by annealing cycle numbers. However, multistage ANN showed stronger resistance to enzyme hydrolysis.

Enhanced Elderberry Snack Bars: A Sensory, Nutritional, and Rheological Evaluation.

Interest in functional foods is continuously increasing, having the potential to be an ally in reducing cardiometabolic risk factors. This study focuses on developing and evaluating oat- and millet-based snack bars enriched with freeze-dried elderberry powder (FDEBP), aiming to combine great taste with enhanced nutritional value, antioxidant properties, and prebiotic potential. The research encompassed a sensory evaluation, nutritional assessment, and rheological analysis of the snack bars. A hedonic test was conducted to gauge consumer preferences and overall liking, providing insights into taste, texture, and acceptance. Sensory evaluation revealed positive feedback from participants, and acceptance rating scores ranged from 7 to 8.04, the best score recorded by one of the enhanced bars with 1% FDEBP. The rheological analysis determined the bars' dynamic storage modulus (G') and loss modulus (G″), assessing the material's elasticity and mechanical properties. Results showed that the incorporation of 0.5% and 1% FDEBP in the oat and millet snack bars significantly impacted their rheological properties, enhancing structural strength. Nutritional analysis demonstrated that the snack bars provided a complete mix of macronutrients required in a daily diet. The study sheds light on the potential of functional snack bars enriched with FDEBP, offering a delectable way to access essential nutrients and bioactive compounds in a minimally processed form, without the addition of sweeteners or additives, friendly to the gut microbiota.