Strong Gel Research Articles

Valorization of Spent Coffee Grounds Oil for the Production of Wax Esters: Enzymatic Synthesis and Application in Olive Oil Oleogels

Spent coffee grounds, the main by-product of the coffee-brewing process, were valorized as a renewable source of lipids for the synthesis of novel wax esters and as an alternative and sustainable oil-structuring agent for the production of oleogels. The lipase-catalyzed reactions were implemented using fatty alcohols both under solvent-free conditions and with limonene as an environmentally friendly solvent. Wax esters were evaluated for their ability to formulate olive oil oleogels through the determination of the physical properties of oleogels. Results showed that high conversion yields were achieved when cetyl and behenyl alcohols were applied under solvent-free conditions, achieving a maximum yield of 90.3% and 91.7%, respectively. In the presence of limonene, the highest conversion yields were 88.9% and 94.5% upon the use of cetyl and behenyl alcohols, respectively. The behenyl wax esters exhibited greater oil-structuring properties, regardless of whether they were derived from solvent or solvent-free conditions. Rheological curves showed that the produced oleogels exhibited a strong gel strength, which was enhanced as the wax ester concentration increased. Frequency sweep curves confirmed the formation of a stable three-dimensional oleogel network and revealed the low dependence of the storage modulus on frequency. Overall, this study demonstrated that producing wax esters from renewable lipid sources has the potential to serve as an effective circular economy paradigm for creating novel oleogels with a broad range of applications.

Colloidal state-based studies on the chloride salts of magnesium- and calcium-induced coagulation of soymilks.

Chloride salts (MgCl2 and occasionally CaCl2) coagulation of the heated soymilks is the key step in manufacturing traditional tofu. In this study, colloidal state diagrams were constructed first, and then the effects of processing parameters, including coagulant concentration, preheating intensity, protein concentration, and coagulation temperature as well as the intrinsic properties (phytate concentration) on the microstructure, protein coagulability, and water holding capacity (WHC) were investigated to gain an overall framework understanding of the Mg2+ and Ca2+ coagulated soymilk process. As the variables changed, the coagulated soymilks displayed one of the following states: colloidal suspension, flocs, weak gel, and strong gel. The microstructures of the coagulated systems also changed to different features with the variation in processing parameters and phytate concentrations. Several interesting results were obtained. It was found that the transformations from colloidal suspension to gel state were usually corresponding to the increase of particle size, the decrease of porosity, and a sharp increase in protein coagulability. The colloidal states of Mg2+ and Ca2+ coagulated soymilks were usually different, but their microstructures were similar. With the increase of protein concentration, the protein coagulability decreased but the WHC was enhanced. The presence of high phytate contents led to form small protein agglomerates, which resulted in worse protein coagulation and WHC. It is expected that this study will deepen the understanding of chloride salts coagulation process.

Improving the Gelation Properties of Pea Protein Isolates Using Psyllium Husk Powder: Insight into the Underlying Mechanism.

The industrial application of pea protein is limited due to its poor gelation properties. This study aimed to evaluate the effects of psyllium husk powder (PHP) on improving the rheological, textural, and structural properties of heat-induced pea protein isolate (PPI) gel. Scanning electron microscopy (SEM), intermolecular forces analysis, the quantification of the surface hydrophobicity and free amino groups, and Fourier transform infrared spectroscopy (FTIR) were conducted to reveal the inner structures of PPI-PHP composite gels, conformational changes, and molecular interactions during gelation, thereby clarifying the underlying mechanism. The results showed that moderate levels of PHP (0.5-2.0%) improved the textural properties, water holding capacity (WHC), whiteness, and viscoelasticity of PPI gel in a dose-dependent manner, with the WHC (92.60 ± 1.01%) and hardness (1.19 ± 0.02 N) peaking at 2.0%. PHP significantly increased surface hydrophobicity and enhanced hydrophobic interactions, hydrogen bonding, and electrostatic interactions in PPI-PHP composite gels. Moreover, the electrostatic repulsion between anionic PHP and negatively charged PPI in a neutral environment prevented the rapid and random aggregation of proteins, thereby promoting the formation of a well-organized gel network with more β-sheet structures. However, the self-aggregation of excessive PHP (3.0%) weakened molecular interactions and disrupted the continuity of protein networks, slightly reducing the gel strength. Overall, PHP emerged as an effective natural gel enhancer for the production of pea protein gel products. This study provides technical support for the development of innovative plant protein-based foods with strong gel properties and enriched dietary fiber content.

Remarkable Stability of Glutathione-Based Supramolecular Gel in the Presence of Oxidative Stress from Hydrogen Peroxide.

Low molecular weight 7-methoxy-3-(p-nitrophenyl)iminocoumarin (MNI) with donor and acceptor groups has been synthesized. The molecule shows typical π-stacking geometry in the crystal structure. In this study, MNI, an achiral small organic molecule, forms a nanostructured supramolecular gel along with a short peptide sequence glutathione (GSH). The self-assembly of the achiral organic coumarin component and chiral biomolecule produces a chiral gel with helical fiber structures. Interestingly, the helicities of chiral gels are controlled by the solvent ratio, where MNI in DMSO and GSH in water has been used. Variation of the solvent ratio from 6:4 to 1:9 for DMSO:H2O results in six gels (4, 5, 6, 7, 8 and 9), where the gel numbers signify the water content ratio. FE-SEM analysis shows gel fibers with right-handed helical structures, which have been further confirmed by circular dichroism (CD) with notable helicity in 4 to 6. This is the first report of controlled chiral helical nanostructured supramolecular gel formation by a solvent mixture with an organic small molecule and biomolecule. Interestingly, storage modulus (G') initially decreases from 4 to 6 and further increases up to 9. An opposite strain (%) trend was observed among these six gels. These unusual solvent-dependent gel properties have been further applied to monitor the stability of the gels in the presence of hydrogen peroxide (H2O2), which converts GSH to oxidized glutathione (GSSG) in general. The oxidative stress from H2O2 disrupts 4 to 6 gels, and precipitation occurs. It is noteworthy to mention that GSSG alone cannot form a gel with the MNI molecule and forms a precipitate. Remarkably, on the other hand, 7 to 9 remain as strong gels even after H2O2 treatment. Among all six gels, 9 shows extraordinary stability of gels even after H2O2 treatment.

Effects of fermentation with Lactobacillus plantarum on rice flour: The role of granular characteristics

This study examined the effects of lactic acid bacteria fermentation on the physicochemical and functional properties of the flours from two rice varieties, Shindongjin (SF) and Hitomebore (HF), both with similar amylose content. Fermentation with Lactobacillus plantarum over 48 h resulted in significant changes. Protein content decreased substantially in both varieties, especially in SF, and amylose content increased. Swelling power and solubility also increased more in SF. The gel hardness of fermented SF increased by approximately 22 %, whereas HF showed minimal change. These differences are due to variations in granule rigidity and starch molecule leaching. SF granules maintained rigidity and a robust external network due to higher amylose leaching. In contrast, the lower initial rigidity and higher amylopectin leaching in HF hindered strong gel network formation. These findings offer insights into the structural and molecular mechanisms of rice fermentation with lactic acid bacteria.

Removal of trace Na and K metal ions by resin-grafted crown ether for electronic-grade N-methyl pyrrolidone purification

The semiconductor industry’s rapid evolution necessitates ultra-high-purity N-methyl pyrrolidone (NMP) as an essential electronic-grade solvent. The development of an efficient coordination material to reduce trace metal ions, particularly Na and K metal ions, to below 1 ppb in NMP solution is a significant challenge. To address this, a novel coordination material, St-DVB-g-ACE, has been developed for the removal of Na and K metal ions from NMP. The material was synthesized by grafting 4′-aminobenzo-15-crown-5-ether onto a strong acid gel resin. The resulting St-DVB-g-ACE-3 exhibited excellent coordination performance for Na and K metal ions, with maximum Langmuir adsorption capacities reaching 20,000 μg/g and 33,333 μg/g, respectively. Of particular interest was the ability of St-DVB-g-ACE-3 to reduce all trace metal ions in industrial-grade NMP to below 1 ppb within a fixed bed column, achieving the stringent requirements for electronic-grade NMP at the G3 level. Additionally, the absorbent enhances the purity of NMP from 99.82 % to 99.84 %, indicating that the material is not dissolved and can exist stably in NMP. Its excellent recyclability and reproducibility make it highly practical for industrial use. Density functional theory (DFT) simulation, complemented by spectral analyses, revealed the interaction force and thermodynamic properties between Na and K metal ions and crown ether ring, and illustrated the interaction between anionic sulfonic group (−SO3−) and metal ions. The prepared resin-grafted crown ether adsorbents are highly effective in the thorough removal of trace metal ions from NMP solution, offering a novel and effective method for the production of electronic-grade NMP.

Carob pulp flour as an innovative source of bioactive molecules for the preparation of high-value-added jellies

The rising demand for healthier alternatives to traditional sugary products has driven the exploration of natural substitutes for sucrose. This study aimed to investigate carob pulp flour (CPF) as a viable alternative to sucrose in the production of high-value jellies with enhanced health benefits. Carob pulp flour was spectroscopically characterized, revealing the presence of bioactive molecules, such as natural antidiabetic polyols and polyphenols. Colorimetric tests demonstrated a significant concentration of polyphenolic molecules in CPF, with a remarkable scavenging activity against radical species in both organic and aqueous environments. Jellies based on CPF (CGC) were successfully prepared and exhibited strong antioxidant activity against ABTS (IC50 0.158 mg mL−1) and DPPH (IC50 0.175 mg mL−1) radicals, maintaining their properties over 15 days, unlike the sucrose-based control, which showed no antioxidant activity. The CPF-enhanced jellies consistently demonstrated higher G′ values (in the range 20–35 °C) than the sucrose-based jellies, indicating improved consistency, elasticity, and strong gel properties, even at higher temperatures. Sensory analysis revealed significant differences, with CPF-based jellies displaying enhanced chocolate (2.3 ± 1.0), ripe fruit (2.3 ± 1.8), and caramel odors (2.0 ± 0.9), as well as increased bitterness and astringency, reduced sweetness, and improved texture. Additionally, CPF-based jellies exhibited significant hypoglycemic properties, with dose-dependent inhibitory effects on α-amylase (57.7 %) and α-glucosidase (50.3 %), and a moderate lipase inhibitory effect (48.6 %) at the maximum concentrations tested. The findings of this study highlight the potential of CPF as a functional ingredient in the food industry, offering a healthier alternative to sucrose in jelly production. The inclusion of CPF not only enhances the antioxidant and sensory properties of jellies but also contributes to significant hypoglycemic effects, making it a promising candidate for the development of functional foods with added health benefits.

Comparing gastric emptying of cellulose nanocrystals with sodium alginate and pectin using a dynamic in vitro stomach model

Cellulose nanocrystals (CNC) are increasingly recognized for their potential in various applications, including packaging, cosmetics, and biomedical engineering. Due to their gelation properties influenced by pH and ionic strength, CNC could impact gastric emptying and satiety, beneficial for managing obesity and diabetes. This study investigated the gastric emptying of CNC (4 % and 8 %, w/w) in comparison with sodium alginate (2 %, w/w) and pectin (2 %, w/w), exploring the effect of divalent cations (Ca2+ and Mg2+) using a dynamic gastric digestion model. CNC, in the presence of Ca2+ and Mg2+, formed a high-viscosity gel network under gastric conditions, leading to delayed gastric emptying. While alginate formed strong gels with Ca2+, it did not significantly delay gastric emptying due to the poor water-holding capacity of its gel network. Pectin showed minimal impact on gastric emptying. Among the treatments, the half-time (t1/2) of gastric emptying for 8 % CNC with Ca2+ was observed to be the longest at 215.4 ± 23.7 min, compared to the shortest times observed with pectin at 15.1 ± 1.4 min. The results suggest that different mechanisms are involved in the gastric emptying effect of different dietary fibers, and CNC is more effective than alginate and pectin assisting in promoting gastric retention and aiding in the management of body weight. This study also introduced a novel application of the dynamic gastric digestion model for estimating digestion energy expenditure, providing insights into the impact of dietary fiber on gastric emptying and satiety enhancement.

The impact of κ-carrageenan on the pea protein gelation by high pressure processing and the gelling mechanisms study

The transition toward sustainable and health-conscious diets has intensified plant-based proteins, particularly pea protein. This research explored the gelation mechanisms of pea protein with κ-carrageenan by high-pressure processing (HPP) as an alternative to traditional thermal methods. Suspensions containing 15% pea protein with 0.1–1% κ-carrageenan were subjected to HPP at 100–600 MPa for 5–30 min. Increasing κ-carrageenan concentration reduced the pressure required to obtain good gels, rendering HPP more energy efficient. Pea protein gels with 1% κ-carrageenan at 600 MPa demonstrated a 27-fold increase in compressive strength compared to 15% pea protein alone by HPP and over 5 times the strength of heat-induced counterparts. Gel textures could be tailored by modulating HPP conditions and κ-carrageenan concentrations. Fourier transform infrared spectroscopy, confocal laser scanning microscopy, and scanning electron microscopy characterized protein unfolding, phase separation, and network formation to study the gelation mechanisms. Results revealed that HPP induced protein tertiary structure unfolding, facilitating phase separation and uniform submicron κ-carrageenan particle distribution in the protein matrix. This, along with a more compact protein network induced by HPP, enhanced gel strength, compensating for limited cysteine in pea protein for disulfide bonds. Higher pressures intensified protein unfolding and aggregation, with κ-carrageenan particles evenly distributing into smaller particles, further strengthening gel structures. Conversely, heating-induced gelation caused more random protein aggregation, leading to coarser and weaker gel networks. This research highlights HPP's effectiveness over traditional heating methods in preparing strong pea protein gels with minimal κ-carrageenan and provides preliminary insights into tailoring HPP and κ-carrageenan for desirable gel textures.

Investigation on the microscopic mechanism of curdlan with different strengths formed by heating

SummaryIn this study, temperature‐dependent changes in the molecular conformation of curdlan were investigated using differential scanning calorimetry (DSC), microscopic observation, particle size analysis and molecular dynamics (MD) simulation. The DSC results showed that the gel formation temperature of curdlan is related to the glass transition temperature (Tg). The results of microscopic observation and particle size analysis showed that the curdlan particles swelled with increasing temperature, and the original rough and irregular surface morphology gradually became relatively smooth. The MD results show that the weak gel is the result of hydrogen bonds and hydrophobic interaction, whereas the strong gel is less affected by hydrogen bonds, and hydrophobic interaction is the main driving force.

Determination of hexachlorophene residue in fruits and vegetables by ultra-high performance liquid chromatography-tandem mass spectrometry.

A modified QuEChERS (Quick, Easy, Cheap, Effective, Rugged and Safe) -LC-MS/MS method was developed for the determination of hexachlorophene in fruits and vegetables. Samples were extracted by acetonitrile and then salted with an acetate buffer system. Extractants neutral alumina (Al-N), strong cation exchange silica gel bonded adsorbent (SCX) and graphitized carbon black (GCB) were used for sample purification. The method demonstrates excellent accuracy and reproducibility. Under optimized conditions, the correlation coefficients of hexachlorophene were higher than 0.995 in the range of 0.5-20 ng/mL. The limit of quantification (LOQ) was 2.0 μg/kg. The average recoveries, assessed at three spiked levels (2.0, 4.0, and 20.0μg/kg) across various matrices including cabbage, celery, tomato, eggplant, potato, radish, cowpea, chives, apple, peach, grape, citrus, bitter melon, banana and hami melon ranged from 72.0 to 100.5% with relative standard deviations from 3.2 to 9.8% (n = 6).

PH-responsive hydrogel containing curcumin-loaded lipid nanocapsules for oral curcumin’s stability, bioaccessibility and intestinal absorption improvement

A liquid formulation with suitable consistency and sustained release characteristics can improve compliance in users with dysphagia.In the study, we prepared curcumin-loaded lipid nanocapsules (Cur-LNCs) and incorporated it in a mixture of sodium alginate, dextrin, calcium chloride and sodium citrate to form a pH-responsive pre-hydrogel solution (SA-DEX:Cur-LNCs). The SA-DEX:Cur-LNCs exhibited a pH-responsive solution-gel conversion: solubilized at near neutral (pH = 7) and rapidly gelatinized to a strong elastic gel at stomach acid (pH = 2.5). The SA-DEX:Cur-LNCs could effectively improve the thermal and pH stability of Cur, and maintain its antioxidant effect. Interestingly, the bioaccessibility of SA-DEX:Cur-LNCs in gastrointestinal was significantly increased to 37.00% when compared with free Cur. The SA-DEX:Cur-LNCs also significantly improved the small intestinal absorption of Cur, being 16 times higher than that of free Cur. Therefore, incorporating lipid nanocapsule in pH-responsive pre-hydrogel provided a new oral administration platform of hydrophobic bioactive compounds for compliance improvement of users with dysphagia.

Exploring the interface dynamics of emulsion gel via a novel non-destructive technique provides insights into the underlying mechanism of gel formation, water mobility, functionality and structural variations

Tri-frequency ultrasound (TFU) at 20-40-60 kHz was used to systematically examine the effects on the multi-scale network structure of an emulsion gel containing orange essential oil prepared with glycosylated whey protein (WP). Treatment intervals of pre-and-post 10, 20, and 30 min were utilized to evaluate the influence and interactions on functional (particle size, zeta-potential), rheological (storage modulus (G′) and loss modulus (G″), and oxidative stability (conjugated diene and peroxide value). The optimized tri-frequency pre- and post-treated sample demonstrated enhanced physical stability as compared to the un-treated sample, as evidenced by droplet size, (from 468.14 ± 0.56 to 214.21 ± 0.42 nm), ζ-Potential (mV) (from −29.67 ± 0.31 to −39.98 ± 1.42), and structural morphology. Structure analysis using FTIR that the aforementioned improvements were made possible through TFU enhanced hydrogen bonds, molecular arrangements with greater order, and improved intermolecular compatibility. XRD results showed gradual shift from 8.32° to 8.64° and from 19.2° to 19.5°, respectively. TFU post-treatment gels exhibited higher viscosity, more pronounced pseudoplastic behavior compare to pre-treatment, attributed to strong interaction forces and three-dimensional gel network. Our results provide valuable insights into the application of multi-frequency ultrasound as a promising technique for designing protein emulsion gels tailored for nutrient delivery systems.

Structural characteristics and gelling properties of citrus pectins after chemical and enzymatic modifications: Conformation plays a vital role in Ca2+-induced gelation

Due to the excellent health benefits of rhamnogalacturonan I (RG-I)-enriched pectin, there has been increasing research interest in its gelling properties. To elucidate its structure–gelation relationship, chemical modifications were used to obtain RG-I-enriched pectin (P11). Then, enzymatic modification was performed to obtain debranched pectins GP11 and AP11, respectively. The effects of RG-I side chains on structural characteristics (especially spatial conformation) and gelling properties were investigated. Among the low-methoxylated pectins (LMPs), AP11, with a loose conformation (Dmax 52 nm) showed the poorest gelling, followed by GP11. In addition to primary structure, spatial conformation (Dmax and Rg) also showed strong correlations (r2 > 0.8) with gelation. We speculate that compact conformation may shorten distance between pectin chains and reduces steric hindrance, contributing to formation of strong gel network. This is particularly important in LMPs with abundant side chains. The results provide novel insights into relationship between spatial conformation and gelling properties of RG-I-enriched pectin.

Exploring the phase behavior of natural egg yolk-carboxymethyl cellulose concentrate: Impact on emulsification and gelling properties

This study developed a dilution-phase diagram method to determine the phase behavior of concentrated egg yolk-carboxymethyl cellulose (EYCM). The results demonstrated that the strength of the electrostatic interaction (SEI) was within the strength limit (1314 mV2), and selective patch binding dominated the formation of soluble complexes. An SEI beyond the strength limit of electrostatic repulsion dominated the formation of alkaline co-solubility. The complex coacervates were formed due to strong electrostatic attraction at SEI > −100 mV2. The acidic co-solubility was formed due to the protonation of carboxymethyl cellulose (CMC). Spectroscopic analysis revealed that the stability of the EYCM spatial structure of the soluble complex was due to the stabilized hydrophobic core, the low content of unstable irregular coils (23.12%) and the high content of highly stabilized β-sheets (24.36%). The different phase behaviors of EYCM affected the emulsification and gelation properties. The acidic and alkaline environments led to co-solubility of the EYCM of a smaller particle size (<362.7 nm), which exhibited a better emulsifying activity. A suitable particle size and depletion attraction improved the emulsification activity and stability of the soluble complexes. Although the complex coacervates had a larger particle size (4160.1 nm), the free CMC-induced depletion attraction contributed to the favorable emulsion stability. In addition, for alkaline co-solubility, the intermolecular folding of LDL, lipid filling and CMC enhancement of the gel framework to form a strong gel. As acidification proceeded, protein unfolding was restricted, the role of lipids and CMC was reduced, and the gel structure gradually diminished.

Fabrication of strong and elastic HIPPEs gel by rigid-flexible double network structure as a novel adipose tissue substitutes

Fat mimics are one of the most common substitutes for animal fats in processed foods. However, basing on high internal phase Pickering emulsion (HIPPEs) gel imitate adipose tissue to achieve the desired strength and elastic, while the formation and stabilization mechanism are barely understood. Here, we proposed a strategy to fabricate rigid-flexible double network using κ-carrageenan (CA) and bacterial cellulose (BC), in oder to improve the mechanical performance of HIPPEs gel. The effects of different ratios of CA/BC (2:1, 4:1, 8:1) and K+ addition on the properties of HIPPEs-CA/BC gels were investigated. Results showed that HIPPEs-CA/BC 8:1 & K+ exhibited better rheological, textural, oil holding capacity and organoleptic properties. Thermal softening behavior of HIPPEs-CA/BC 8:1 & K+ was similar to the pork adipose tissue. The microstructure of gel demonstrated that HIPPEs-CA/BC 8:1 & K+ was featured with honeycomb-like pore and network walls, which in turn comprise interpenetrated double network structures. Meanwhile, it showed an ultrahigh stress, high Young's modulus and good cyclic compress behavior. Additionally, the hydrogen bonds and K+-cross-linked were proved to play crucial roles in facilitating the formation of a stable and elastic CA/BC matrix. This study establishes structure-performance mechanisms in strongly and elastically structured HIPPEs gels, providing an advanced strategy for developing HIPPEs gel with promising applications in adipose tissue substitutes.

Extraction and characterization of pectin from coffee (Coffea arabica L.) pulp obtained from four different coffee producing regions

The pectin was extracted using H2SO4, HNO3, and HCl from the pulp of four coffee varieties (Harar, Sidama, Jimma, and Guji) collected from different regions of Ethiopia. The effect of extraction temperature, time, solid-to-liquid ratio, types of acid and coffee varieties on the physiochemical properties and yield of pectin were studied. A maximum pectin yield, which was 12.7 %, was obtained from Harar coffee pulp treated with H2SO4. The equivalent weight of the extracted pectin varied from 1111 to 1667 g/mol. The methoxyl contents of the extracted pectin ranged from 4.23 to 7.13 %. The degrees of esterification and anhydrouronic acid of the pectin ranged from 53 to 68.5 % and 35.5 to 68.8 %, respectively. The results show the yield and physiochemical properties of the coffee pulp pectin depend on extraction parameters, acid types, and coffee varieties. Moreover, the pectin extracted from coffee pulp showed strong gelling properties.

Strong and Thermo-Switchable Gel Adhesion Based on UCST-Type Phase Transition in Deep Eutectic Solvent.

It remains a great challenge to achieve strong and reversible hydrogel adhesion. Hydrogel adhesives also suffer from poor environmental stability due to dehydration. To overcome these problems, here reversible adhesive gels are designed using a new switching mechanism and new solvent. For the first time, the study observes UCST (upper critical solution temperature)-type thermosensitive behaviors of poly(benzyl acrylate) (PBnA) polymer and gel in menthol:thymol deep eutectic solvents (DESs). The temperature-induced phase transition allows adjusting cohesive force, and hence adhesion strength of PBnA gels by temperature. To further improve the mechanical and adhesion properties, a peptide crosslinker is used to allow energy dissipation when deforming. The resulting eutectogel exhibits thermal reversible adhesion with a high switching ratio of 14.0. The adhesion strength at attachment state reaches 0.627MPa, which is much higher than most reversible adhesive hydrogels reported before. The low vapor pressure of DES endows the gel excellent environmental stability. More importantly, the gel can be repeatedly switched between attachment and detachment states. The strong and reversible gel adhesive is successfully used to design soft gripper for the transport of heavy cargos and climbing robot capable of moving on vertical and inverted surface in a manner similar to gecko.

Comparison of dry (air classification) and wet fractionated pea protein on protein molecular structure and gelling properties

AbstractDry fractionation is an environmentally friendly and cost‐effective method to separate protein fractions. While most research has focused on the structure and functional properties of pea protein isolates (PPI), the information on dry fractionated pea protein (DFPP) is limited. This study compared DFPP (protein content (PC): 50.7%, insoluble fiber: 17%), to PPI (PC: 80.1%, insoluble fiber: 8.33%), in terms of the protein structure, solubility, and heat‐induced gelation. SDS‐Page, size‐exclusive chromatographic, and Fourier‐transform infrared spectrophotometer analysis indicated that DFPP contained the major protein components in pea, and their native structures were well maintained. Whereas for PPI, some proteins were lost during wet extraction, and partial protein unfolding and aggregation were observed. At neutral pH, DFPP showed significantly higher solubility (44.64 ± 0.55%) than PPI (12.09 ± 1.42%). Interestingly, DFPP showed good gelling capacity as reflected by lower gelling concentration and higher gel mechanical strength and elasticity compared to those made from PPI. The DFPP gels were twice higher in mechanical strength (7.71 ± 0.21 kPa) than that prepared from PPI at pH 7. Strong gels were also obtained for DFPP at pH 5. The gel morphology revealed phase separation between protein and polysaccharides by heating, with stick‐shaped fiber (10–25 μm) dispersed in the continuous protein networks. Eventually, the polysaccharides including fiber and starch helped strengthen the gel network by acting as fillers. This knowledge will help to expand the applications of DFPP as a gelling ingredient in food formulations, but also allow industry to benefit from the dietary fiber co‐exist in the protein to develop healthier food products using a holistic approach.

Evaluating the Performance of Class F Fly Ash Compared to Class G Cement for Hydrocarbon Wells Cementing: An Experimental Investigation.

The following study presents the results of research in the field of the performance of geopolymers consisting of Class F fly ash with an alkaline activator solution consisting only of sodium metasilicate (Na2SiO3) and water. The performances of this geopolymer are compared to the those of American Petroleum Institute (API) Class G cement. This comparison is to evaluate the potential of the geopolymer as an alternative to cement in cementing hydrocarbon wells in the oil and gas industry. The gap in the research is determining the performance properties that restrict the use of fly ash in the oil and gas industry. Using only sodium metasilicate as an activator with water, the solution creates a strong binding gel for the geopolymer and activates the aluminosilicate properties of the fly ash. This geopolymer is compared with Class G cement without additives to determine their base performances in high pressure and high temperature conditions, as well as note any properties that are affected in the process. This commences by formulating recipes of these two materials from workable ratios and concentrations. The ratios are narrowed down to the best working models to proceed to comparative performance testing. The tests included exploring their vital performances in fluid loss and thickening time. The results produced suggest that Class G cement generally has less fluid loss at low temperature than the geopolymer but could not maintain its integrity and structure as temperatures increased. Class G cement exhibited stability, consistencies of 100 Bcs (Bearden Consistency Units), and a faster thickening time of 1 h and 48 min when placed under high temperature and high-pressure conditions, respectively. However, the geopolymer showed more consistency regarding fluid loss with respect to rising pressure and temperature, and smoother, less fractured samples emerging from both tests. Though the geopolymer showed stronger performances in thickening and water retention, the experiments showed that it is not a uniform and consistent material like Class G cement. Through the use of different additives and intricate design, the sample may show success, but may prove more difficult and complex to apply than the industry standard and uniform content of Class G cement.