The aquafaba was prepared from chickpeas soaked for 24 hours and then pressure-cooked for 120 minutes. The cooking liquid was separated from the chickpeas, and its pH was measured at 6.15 ± 0.01 before being adjusted to approximately 5 with lemon juice. Its protein concentration was 1.12% on a wet basis and 17.42% on a dry basis, compared with 9.24% and 73.002% for egg white.

Aquafaba also contained less total material: its total solid content was 6.42%, compared with 12.69% for egg white. These compositional differences were consistent with the aquafaba’s lower ability to expand and stabilize foam in the study’s standardized whipping test. That test produced a marked difference between the two foaming ingredients.

After whisking, egg white reached 781.66% foaming capacity, meaning a much larger volume relative to the initial sample, while aquafaba reached 326.66%. Foam stability after 30 minutes was 97.22% for egg white and 84.03% for aquafaba. Aquafaba is not a single-component foaming agent: the study describes it as a mixture containing soluble proteins, saponins, carbohydrates, polysaccharides and fibrous components.

Proteins and saponins can contribute at interfaces, while soluble carbohydrates and polysaccharides influence the continuous phase. The measured gap nevertheless showed that the chickpea cooking liquid could foam, but did not match the expansion or persistence of egg white under the tested conditions. The researchers selected meringue as a relatively simple model of a foam and pancakes as a more complex fluid system containing starch granules, proteins and lipids.

For pancakes, the control contained 100 g of wheat flour, 40 g of egg white, 20 g of sugar, 2 g of salt, 4.5 g of baking powder and 108.5 g of water. The 50% formulation replaced 20 g of egg white with 20 g of aquafaba, while the 100% formulation replaced all 40 g of egg white with 40 g of aquafaba. For meringue, the formulations contained 250 g of powdered sugar and either 250 g of egg white, 125 g each of egg white and aquafaba, or 250 g of aquafaba.

All formulations were produced in three independent batches, with triplicate analyses and three technical replicates per production replicate. Replacing egg white lowered the density of both product types, a measured indication that the mixtures incorporated more air. Pancake batter density declined from 1.123 ± 0.003 g/mL in the egg-white control to 1.077 ± 0.03 g/mL at 50% substitution and 1.049 ± 0.03 g/mL at full substitution.

Meringue foam density fell from 0.156 ± 0.001 g/mL in the control to 0.138 ± 0.002 g/mL with 50% aquafaba and 0.123 ± 0.001 g/mL with complete replacement. These differences were significant at p < 0.05. Aquafaba therefore generated aerated systems, but the decrease in density did not translate into a stronger final structure.

Rheological measurements were conducted at 25°C and 1 Hz, equivalent to 6.28 radians per second, with strain amplitudes from 0.01% to 200%. In the linear viscoelastic region, the elastic modulus, G′, exceeded the viscous modulus, G″ for all pancake and meringue samples, indicating predominantly elastic, solid-like behavior. The egg-white controls had the highest modulus values.

Aquafaba reduced the elastic response, particularly in meringue, whose G′ values ranged from 0 to 1,600 Pa, compared with a G″ range of 0 to 400 Pa. Pancake G′ and G″ values ranged from 0 to 200 Pa and 0 to 100 Pa, respectively. Aquafaba also shifted the G′–G″ crossover in meringue to lower strain, showing that the substituted foams entered nonlinear behavior earlier.

The nonlinear response also differed by product. Meringues exhibited Type III weak strain overshoot: as strain increased, G′ declined and G″ rose before G″ decreased at the highest strains, a pattern associated with irreversible deformation and flow. At 200% strain, the pancake systems returned to strain softening after earlier strain stiffening, while the meringues shifted from shear thickening to shear thinning.

Chebyshev harmonic analysis gave the same broad distinction: pancakes showed positive third-to-first elastic coefficients and negative viscous coefficients in the nonlinear region, whereas meringues initially showed positive ratios for both before the viscous response became negative at 200% strain. Large-amplitude Lissajous–Bowditch curves separated the elastic and viscous parts of each stress cycle and showed that aquafaba reduced both stored and dissipated energy. The effect was especially pronounced in meringue made with 100% aquafaba.

Wider elastic stress loops in aquafaba-containing pancake samples indicated greater irreversible structural breakdown during flow, while narrower viscous loops and a more fluid-like response in fully substituted meringue indicated altered energy dissipation. The large-strain-to-minimum-strain elastic modulus and viscosity ratios also described the shift from linear to nonlinear behavior. Together, these observations indicated lower mechanical resistance in aquafaba-containing systems, even though the overall types of nonlinear response remained similar across the formulations.

Texture analysis confirmed that the baked products became softer as the replacement level increased. Control pancakes had a hardness of 47.49 ± 0.51 N, compared with 43.42 ± 0.52 N for the 50% formulation and 38.26 ± 2.03 N for the 100% formulation. Springiness, gumminess, chewiness and elasticity also generally decreased with more aquafaba.

For meringue, hardness fell from 69.37 ± 2.28 N in the control to 51.34 ± 1.93 N at 50% replacement and 43.28 ± 1.18 N at full replacement. Meringue fracturability declined from 60.09 ± 1.86 N to 47.67 ± 1.46 N and 42.68 ± 1.59 N, respectively. The texture measurements were consistent with the lower density, modulus and energy responses observed in the rheological analysis.

Scanning electron microscopy and cross-sectional images showed structural changes associated with the lower mechanical resistance. Pancakes containing higher proportions of aquafaba displayed fewer visible pores, while aquafaba-based meringues developed more layered and fragile structures. The images support the interpretation that the mixtures initially incorporated air but were less effective at retaining that aerated architecture during baking.

Color also changed with substitution. In pancakes, increasing aquafaba raised crumb brightness but lowered crust brightness; the highest redness values for both crumb and crust occurred in the 50% formulation. The authors associated the crust differences with the sugars and polysaccharides in aquafaba and their possible influence on Maillard browning and caramelization.

Overall, the study shows that aquafaba can perform useful foaming and structural functions in pancakes and meringues, but it does not reproduce the mechanical resistance of egg white. Its use produced lower-density, softer products with less capacity to withstand large deformation, and microscopy indicated less effective retention of incorporated air during baking. The authors identified several limitations and directions for further work: composition can vary with chickpea cultivar, genotype and preparation conditions, so future studies should test how protein, saponin, starch and soluble-carbohydrate contents affect air incorporation, deformation resistance and structural retention.

The same large-amplitude rheological approach could also be applied to other plant-based, high-shear foods. Sensory assessment, consumer acceptance and shelf-life studies would be needed before the practical performance of the most promising formulations could be fully evaluated.

Subject of Research: Laboratory assessment of aquafaba as an egg-white substitute in pancake batter and meringue foam

Article Title: Investigation of the Effects of Aquafaba Used Egg Replacers on Pancake Batter and Meringue Foam Rheology and Products Properties

Article References: Özyiğit, E., Erkoç, S., Özcan, İ., Kumcuoglu, S., & Tavman, Ş. (2026). Investigation of the Effects of Aquafaba Used Egg Replacers on Pancake Batter and Meringue Foam Rheology and Products Properties. Food Science & Nutrition, 14(10), Article e72392. https://doi.org/10.1002/fsn3.72392

Image Credits: AI Generated

DOI: 10.1002/fsn3.72392

Keywords: aquafaba, egg replacement, pancake batter, meringue foam, food rheology, large-amplitude shear, food texture, chickpea cooking water, plant-based foods, scanning electron microscopy, Investigation, Effects

The scale of the underlying analysis is considerable. The authors screened roughly 1,100 records from major scientific databases including Scopus, Web of Science, PubMed, ScienceDirect, and Google Scholar. After removing duplicates and screening titles and abstracts, 530 studies remained for closer inspection, and 430 underwent full-text assessment against predefined eligibility criteria. The final synthesis drew on 183 studies, spanning molecular mechanisms, physicochemical properties, and industrial applications of both natural and synthetic gelling and foaming agents. This systematic approach matters because knowledge about gelation and foaming has long been scattered across different food systems, from confectionery to dairy to beverages, limiting the development of a unified understanding.

At the molecular level, gelation is a story of networks. A gel forms when dissolved biopolymers assemble into a three-dimensional mesh that traps water and other components, producing the firmness, elasticity, and mouthfeel consumers recognize in jellies, desserts, and confectionery. The review details how different agents achieve this through distinct mechanisms. High-methoxyl pectin, the classic jam-setting polysaccharide, requires an acidic environment around pH 2.5 to 3.5 and high sugar concentrations of 55 to 75 percent. The acid reduces electrostatic repulsion between negatively charged pectin molecules, while sugar binds available water, allowing hydrogen bonds and hydrophobic interactions between methyl ester groups to stabilize junction zones into a thermoreversible network.

Low-methoxyl pectins and alginates take a different route entirely: ionic cross-linking. Alginate, extracted from brown seaweed, gels in the presence of calcium ions through the well-known egg-box model, in which divalent cations nest between the guluronate regions of adjacent polymer chains. This chemistry powers the spherification technique beloved of molecular gastronomy, where an alginate-containing liquid dropped into a calcium chloride solution instantly forms a thin, flexible membrane around each droplet, producing caviar-like spheres. Carrageenans from red seaweed follow yet another path, undergoing a coil-to-helix transition upon cooling before metal ions such as potassium and calcium aggregate the helices into networks. The ion type dictates texture: potassium yields firm, brittle gels with kappa-carrageenan, while calcium produces softer, more elastic structures with the iota form.

Agar demonstrates perhaps the most dramatic thermal behavior of any hydrocolloid. When heated above 85 to 95 degrees Celsius, agarose chains float as random coils; on cooling to between 32 and 45 degrees, they align into ordered double helices stabilized by hydrogen bonds, which then aggregate into a rigid three-dimensional network. The large gap between setting and melting temperatures gives agar gels exceptional thermal stability, remaining solid at room temperature and beyond. This hysteresis, combined with high clarity and low syneresis, explains why roughly 90 percent of extracted agar serves as a gelling agent in meat and fish products and as a texture enhancer in dairy, and why it has become the gelatin substitute of choice for vegetarian and vegan formulations.

Gelatin, the workhorse of confectionery, operates through temperature-induced protein assembly. Derived from the hydrolytic degradation of collagen, it consists largely of glycine, proline, and hydroxyproline, organized into alpha, beta, and gamma polypeptide chains. Dissolved in hot water, its triple-helix structure unwinds into individual strands; as the solution cools, these strands re-form hydrogen bonds and hydrophobic interactions, weaving a mesh that traps water and sets into the familiar semi-solid. Beyond desserts, gelatin retains juices in canned meats, stabilizes marshmallows and gummy candies, and even serves as an edible film material, though its animal origin increasingly conflicts with consumer demand for plant-based alternatives.

Foaming, the review’s second focus, is governed by a different physical principle: the stabilization of gas bubbles within a liquid or semisolid matrix. Proteins act as natural foaming agents because they are amphiphilic, carrying both hydrophilic and hydrophobic regions. When egg whites are beaten, proteins such as ovalbumin and ovotransferrin unfold and realign at the air-water interface, forming a thin elastic film that encapsulates air and lowers surface tension. Surfactants like soy lecithin and monoglycerides perform the same job more efficiently, aligning at the interface to prevent bubble coalescence. In whipped cream, partially coalescing fat globules form a network that locks air bubbles in place, reinforced by a secondary protein layer, producing the smooth, creamy texture essential to consumer satisfaction.

The practical stakes of foam stability extend across the entire food landscape. In bakery, angel food and chiffon cakes depend on egg-white foams that expand during baking, with cream of tartar added to lower the pH and enhance stability. In beverages, the head on beer and the microfoam on a cappuccino both rely on surface-active proteins forming resilient layers around bubbles. In gluten-free baking, where the gluten network is absent, methylcellulose and egg whites provide the aeration and structure needed for a light crumb. Even fats can sabotage the process: oils disrupt the films around air bubbles, forcing formulators to adjust ingredient proportions and processing techniques carefully.

The review also spotlights emerging alternatives driven by the clean-label movement. Aquafaba, the cooking water from chickpeas and other legumes, contains proteins, polysaccharides, and saponins that give it foaming capacity and stability comparable to egg whites in certain applications, making it attractive for vegan and allergen-free formulations. Xanthan gum, produced by bacterial fermentation, remains stable across a remarkable pH range of 2.0 to 12.0 and in high-salt environments, excelling as a foam stabilizer and suspension agent. Yet natural ingredients bring their own problems: batch-to-batch variability in composition, molecular weight, and purity, driven by species, harvest season, and extraction method, can shift gel strength and viscosity unpredictably, complicating industrial standardization.

The authors conclude that the future lies in hybrid systems and advanced processing. Combining polysaccharides with plant proteins may deliver enhanced stability, resistance to thermal degradation, and reduced syneresis in clean-label formulations, while technologies such as high-intensity ultrasound, cold plasma, and high-pressure processing offer ways to tailor the interfacial behavior and rheological properties of non-animal biopolymers to match conventional agents. Ion-induced gelation with gellan gum under high pressure, which sets cold-set desserts without heating, hints at how processing innovation can preserve temperature-sensitive ingredients. Bridging fundamental knowledge of macromolecular interactions with industrial-scale application, the review argues, will be essential for building the next generation of stable, sustainable, and sensory-optimized foods, ensuring that the invisible chemistry inside every jelly and foam keeps pace with what consumers expect on the label.

Subject of Research: Mechanisms and applications of gelling and foaming agents in food systems

Article Title: Review on Gelling and Foaming Agents in Food: Mechanism and Applications

Article References: Kassa, M. G., Teferi, D. A., Satheesh, N., & Asemu, A. M. (2026). Review on Gelling and Foaming Agents in Food: Mechanism and Applications. Food Science &amp; Nutrition, 14(10), Article e72437. https://doi.org/10.1002/fsn3.72437

Image Credits: AI Generated

DOI: 10.1002/fsn3.72437

Keywords: gelling agents, foaming agents, hydrocolloids, pectin, gelatin, agar, carrageenan, alginate, aquafaba, food texture, clean label, plant-based proteins