Foam Formation Research Articles

Effects of Emulsifier Type and Ingredient on the Foam Stability of Meringue

Food foams provide texture and structure for many food products, such as meringues. Meringues, a fundamental of culinary arts, commonly consist of whipped egg white and sugar and have about most of the air phase. These types of composition allow for making different products with the same ingredients; thus, meringue design is essential to investigate foam stability and ability. This study aims to examine the foam stability of meringue using the different components such as protein as emulsifiers (egg white and gelatin) and the composition of sugars (icing and granule) on the foam stability and formation of meringue. Using gelatin as an emulsifier showed the foam more stable than egg white (>24 h), and adding the icing sugar with gelatin made the foam texture smoother. On the other hand, foam formation was faster when using emulsifier egg white, but stability was less than gelatin. The more stable foam produced by the combination of emulsifier and sugar ingredients would provide a better texture of meringue after baking, a smooth surface, no hole, and a more crunchy sweet taste. It was concluded that the composition of the ingredients and type of emulsifier would affect the stability and ability of foam, resulting in the character of the meringue after baking.

Onsite coalescence behavior of whey protein-stabilized bubbles generated at parallel microscale pores: Role of pore geometry and liquid phase properties

In the formulation of (food) foams, an excess of protein is needed to prevent instant coalescence of bubbles from happening at (sub)millisecond time scales. However, protein adsorption and its influences on coalescence stability rarely have been investigated under such conditions of short time scales and high protein concentrations. In the current study, the coalescence stability of whey protein isolate-stabilized bubbles was studied using a microfluidic device, for a wide range of process conditions, including bubble-forming pore geometries and liquid phase properties. The bubble formation time was varied via the applied pressure, and the corresponding extent of bubble coalescence was quantified via the analysis of bubble sizes obtained through high-speed recordings. The experimental results of bubble coalescence as function of bubble formation time, in the presence of various protein concentrations, were also captured in a semi-empirical model. The amount of proteins accumulating at the surface of coalescing bubbles can be derived from a mass balance, with protein adsorption towards the surface of coalescing bubbles assumed to follow a Langmuir isotherm. The model showed a good fit with the experimental results, and we found that as the protein concentration increases from 2.5 to 7.5% wt., in our device the minimum time required to stabilize bubbles decreases from 0.5 to 0.1 ms. From a practical perspective, our microfluidic device can be used as an efficient tool to capture the instant, (sub)milliseconds, behavior of bubble coalescence, providing closer insights for industrial-scale production of (food) foams that also takes place at these time scales.

Design and engineering characterization of a horizontal tubular bioreactor with spiral impeller for cell cultivation

Aerated stirred tank bioreactors (STRs) are the norm for commercial production of biologicals but tend to exert high shear forces from high impeller tip speeds, direct sparging, bubble disruption at the surface and foam formation. In this work, a novel 5 liter horizontal tubular bioreactor (HTB) fitted with a spiral impeller was designed for cell cultures. The abiotic and engineering characterization of the HTB was undertaken in terms of fluid flow pattern, mixing time (θm), minimum agitation speed Njs, volumetric oxygen mass transfer coefficient (kLa), and power consumption (P). The bioreactor showed optimum operability between 2 and 3 litre, and comparable mixing time ranges, power consumption and volumetric oxygen mass transfer coefficients (kLa) between 5 and 16 h−1 to a STR and other conventional systems. An ANOVA analysis disseminated that impeller immersion and mixing speeds had significant effects on mixing times, while aeration rates and mixing speeds significantly impacted kLa. The abiotic and engineering characterization investigations revealed that the bioreactor design supported good surface aeration with bubble entrainment for oxygen mass transfer while imparting low energy into the system, which are key attributes in promoting a low shear environment for cell culturing.

Implementation of Ambon Banana Peel (Musa Paradisiaca) as Foaming Agent of Banana Fruitghurt using Foam Mat Drying Method

Fruitghurt is a product of lactic acid fermentation, namely L. bulgaricus and S. Thermopillus in an acidic state enriched by nutrients from fruit such as Ambon banana but has a short shelf life. Bananas have a role as an additional nutrient in the form of glucose which then becomes a nutrient for lactic acid bacteria. Foam mat drying itself is a drying method that is better than other types of drying because it does not require large production costs and protects the structure of the material through the formation of foam. Application of foam mat drying on fruitghurt using Ambon banana peel extract as a foaming agent is expected to increase the shelf life of fruitghurt as well as an alternative foaming agent derived from vegetable protein Ambon banana peel contains a protein content of about 0.64% when bananas experience a good level of maturity. In the manufacture of fruitghurt powder, the research method used is Response Surface Methodology (RSM) with variables changing the concentration of banana peel extract as a foaming agent, the concentration of maltodextrin as a binder and mixing time. The resulting fruitghurt powder will be analyzed for water content, total acid analysis and pH analysis. The research data were processed using minitab 19 software. The best fruitghurt powder results were found in the 9th variable, namely the minimase variable, where the optimum conditions were banana peel extract concentration of 2.38 ml, maltodextrin concentration of 30 grams and stirring time of 20 minutes. Fruitghurt variable 9 has a pH of 5 after drying which is in accordance with SNI 01-2981-2009, water content is 0.64% and total acid is 1.08%

PENGARUH VARIASI KONSENTRASI HPMC TERHADAP MUTU FISIK DAN STABILITAS SEDIAAN SHAMPO EKSTRAK ETANOL DAUN KATUK (Sauropus androgynus (L) Merr)

The Aims of this study was to determine effect of HPMC concentration variation to etanol extract Sauropus androgynus (L) Merr shampoo physical properties. True experimental laboratories design was used as design study. Shampoo was formulated in three formulation which used HPMC variation consentration were F1 (1%), F2 (2%) , F3 (3%). Shampoo was evaluated physical properties included organoleptic, pH, viscosity, foam forming, and stability test at 6oC, 300C and 40oC. Organoleptic test was observed by visual observation. pH, viscosity, foam forming, and stability test from three formulation were observed by one way anova statistic. The result showed that HPMC concentration variation didn’t influence to physical properties foam forming and pH shampoo but there had influence to physical properties viscosity. All formulation of formulation unstable during 6 weeks storage.

Formulation and evaluation of antidandruff shampoo using mannosylerythritol lipid (MEL) as a bio-surfactant

Abstract Dandruff is a dermatological, harmless, non-inflammatory, chronic scalp condition caused by Malassezia species and recognisable by the white flakes of dead skin in the hair. Mannosylerythritol lipids (MEL) are non-ionic glycolipid surfactants (biosurfactants) with excellent surface-active properties. Their skin compatibility, biocompatibility, biodegradability and remarkable antimicrobial properties make them a potential alternative to conventional surfactants. In the current study, an anti-dandruff shampoo was formulated with different concentrations of sodium lauryl sulphate (SLS) and MEL as surfactants. Two anti-dandruff agents, salicylic acid and benzoic acid, were used. The other ingredients used were xanthan gum, sodium EDTA, urea, Tween 80 and distilled water. The various physicochemical parameters evaluated were colour, clarity, odour, texture, pH, skin irritation, percentage of solid content, dispersibility for dirt, foam formation and foam stability, critical micelle concentration, washability, surface tension, visual stability and antimicrobial test using recommended procedures. The pH ranged from 5.15 to 6.5, the physical appearance was golden yellow, the solids content ranged from 25.1% to 28%, surface tension ranged from 30.64 mN m−1 to 38.00 mN m−1, CMC concentration ranged from 30.14 g/L to 30.16 g/L and foam value ranged from 190 mL to 105 mL. Antimicrobial activity was determined with Staphylococcus aureus (DSM 3463) and Malassezia furfur (ATCC14521). The zone of inhibition ranged from 10 mm to 17 mm (S. aureus) and 14.5 mm to 24 mm (M. furfur), respectively. The shampoo formulated with MEL only (formulation C) showed lower foaming and anti-dandruff activity than the synthetic shampoo (formulation A). However, the anti-dandruff activity increased when MEL was used in combination with SLS (formulation B). This shows that the antimicrobial properties of MEL and SLS together with other antimicrobial agents such as salicylic acid and benzoic acid enhance the properties of the shampoo. SLS can be completely replaced by a combination with biosurfactants to reduce the use of chemical surfactants and improve the anti-dandruff properties.

Surfactant in a Polyol-CO2 Mixture: Insights from a Classical Density Functional Theory Study.

Silicone-polyether (SPE) surfactants, made of a polydimethyl-siloxane (PDMS) backbone and polyether branches, are commonly used as additives in the production of polymeric foams with improved properties. A key step in the production of polymeric foams is the nucleation of gas bubbles in the polymer matrix upon supersaturation of dissolved gas. However, the role of SPE surfactants in the nucleation of gas bubbles is not well understood. In this study, we use classical density functional theory to investigate the effect of an SPE surfactant on the nucleation of CO2 bubbles in a polyol foam formulation. We find that the addition of an SPE surfactant leads to a ∼3-fold decrease in the polyol-CO2 interfacial tension at the surfactant's critical micelle concentration. Additionally, the surfactant is found to reduce the free energy barrier and affect the minimum free energy pathway (MFEP) associated with CO2 bubble nucleation. In the absence of a surfactant, a CO2-rich bubble nucleates from a homogeneous CO2-supersaturated polyol solution by following an MFEP characterized by a single nucleation barrier. Adding a surfactant results in a two-step nucleation process with reduced free energy barriers. The first barrier corresponds to the formation of a spherical aggregate with a liquid-like CO2 core. This spherical aggregate then grows into a CO2-rich bubble (spherical aggregate with a vapor-like CO2 core) of a critical size representing the second barrier. We hypothesize that the stronger affinity of CO2 for PDMS (than polyether) stabilizes the spherical aggregate with the liquid-like CO2 core, leading to a lower free energy barrier for CO2 bubble nucleation. Stabilization of such an aggregate during the early stages of the nucleation may lead to foams with more, smaller bubbles, which can improve their microstrustural features and insulating abilities.

Foam-free production of the rhamnolipid precursor 3-(3-hydroxyalkanoyloxy) alkanoic acid (HAA) by Pseudomonas putida

Surfactants represent a large group of industrial relevant substances and can be generated chemically, but also biologically. Important microbial producers are several Pseudomonas species, mainly known for their ability to produce rhamnolipids. For safety reasons, recombinant Pseudomonas putida is preferred for heterologous production of rhamnolipids as well as its precursor 3-(3-hydroxyalkanoyloxy) alkanoic acid (HAA), which is a promising platform substance. The surface-active properties of HAA combined with classical submerged aeration cause strong foam formation making biotechnological production in stirred tank bioreactors challenging. Therefore, a foam-free bioprocess for HAA production was developed in this study. The combination of headspace aeration, overpressure up to 8 bar, and temperature reduction prevented oxygen limitation, shortened process time, and enhanced the maximum HAA concentration to 1.71 g l− 1 with a space-time yield of 0.08 g l− 1 h− 1.Graphical

Metallic foam with cross flow heat exchanger: A review of parameters, performance, and challenges

AbstractThe cross‐flow heat exchanger involves a tractor moving between two fluids that flow in a direction perpendicular to each other, and one of the fluids is often a liquid and the other is a gas. This type of heat exchanger has been studied in many previous studies for its importance in air conditioning applications and many industrial applications. In this type of heat exchanger, the surface area for heat transfer is very large. Therefore, many techniques have been used to improve the thermal and dynamic performance of this type of heat exchanger. In this study, previous studies that used metallic foam as one of the ways to improve the performance of heat exchangers were reviewed. The most important techniques that were used in previous studies during the process of evaluating the thermal performance of a cross‐flow heat exchanger in the presence of different types of metal foam were clarified. The use of metal foam depends on important factors, including (1) the type of material, where copper and aluminum were used in most of the previous studies, due to their availability and ease of foam formation using these materials, in addition to the good thermal properties, (2) porosity, where the porosity value of metal foam ranged between 0.85 and 0.98 in the previous studies, (3) the density of pores, most of the studies ranged between 10 and 40 PPI.

The Influence of the Surface Chemistry of Cellulose Nanocrystals on Ethyl Lauroyl Arginate Foam Stability.

Guanidine-based surfactant ethyl lauroyl arginate (LAE) and cellulose nanocrystals (CNCs) form complexes of enhanced surface activity when compared to pure surfactants. The LAE-CNC mixtures show enhanced foaming properties. The dynamic thin-film balance technique (DTFB) was used to study the morphology, drainage and rupture of LAE-CNC thin liquid films under constant driving pressure. A total of three concentrations of surfactant and the corresponding mixtures of LAE with sulfated (sCNC) and carboxylated (cCNC) cellulose nanocrystals were studied. The sCNC and cCNC suspension with LAE formed thin films, with stability increasing with surfactant concentration and with complex rheological properties. In the presence of LAE, the aggregation of CNC was observed. While the sCNC aggregates were preferentially present in the film volume with a small fraction at the surface, the cCNC aggregates, due to their higher hydrophobicity, were preferentially located at film interfaces, forming compact layers. The presence of both types of aggregates decreased the stability of the thin liquid film compared to the one for the LAE solution with the same concentration. The addition of CNC to LAE was critical for foam formation, and foam stability was in qualitative agreement with the thin films' lifetimes. The foam volume increased with the LAE concentration. However, there was an optimum surfactant concentration to achieve stable foam. In particular, the very resistant foam was obtained with cCNC suspensions that formed the interfaces with a complex structure and rheology. On the other hand, at high LAE concentrations, the aggregates of CNC may exhibit antifoaming properties.

Lightweight, Thermally Insulating, Fire‐Proof Graphite‐Cellulose Foam

AbstractFoam materials are widely used in packaging and buildings for thermal insulation, sound absorption, shock absorption, and other functions. They are dominated by petroleum‐based plastics, most of which, however, are not biodegradable nor fire‐proofing, leading to severe plastic pollution and safety concerns. Here, a fire‐proofing, thermally insulating, recyclable 3D graphite‐cellulose nanofiber (G‐CNF) foam fabricated from resource‐abundant graphite and cellulose is reported. A freeze‐drying‐free and scalable ionic crosslinking method is developed to fabricate Cu2+ ionic crosslinked G‐CNF (Cu‐G‐CNF) foam with a low energy consumption and cost. Moreover, the direct foam formation strategy enables local foam manufacturing to fulfil the local demand. The ionic crosslinked G‐CNF foam demonstrates excellent water stability (the foam can maintain mechanical robustness even in wet state and recover after being dried in air without deformation), fire resistance (41.7 kW m−2 vs 214.3 kW m−2 in the peak value of heat release rate) and a low thermal conductivity (0.05 W/(mK)), without compromising the recyclability, degradability, and mechanical performance of the composite foam. The demonstrated 3D G‐CNF foam can potentially replace the commercial plastic‐based foam materials, representing a sustainable solution against the “white pollution”.

Enhancing the thermal conductivity of PEG composites with freeze-drying and surface treatment of MXene and CNT

To enhance the thermal properties of polymer composite materials, it is essential to appropriately configure thermal paths. Three-dimensional (3D) thermally conductive networks can serve as an excellent means for building high-speed conductive pathways in polymer composites. The MXene/acid-treated carbon nanotube/polyethylene glycol (MX/O-CNT/PEG) composite material has a 3D foam structure, and the focus is on the acid-treatment of the CNTs and foam formation of the PEG. The thermal conductivity of the synthesized composite material with 40 wt% filler loading and 3D foam was 580% higher than that of pure PEG, and it is superior to that of the composite material prepared by randomly dispersing fillers. Therefore, this work describes an advanced process to significantly improve the thermal conductivity of polymer composites.

Bioaerosol Release from Concentrated Microbial Suspensions in Bubbling Processes

Bursting bubbles are one of the most common mechanisms in aerosols’ formation from natural and artificial waterbodies. The presence of microbial materials in the liquid could cause their aerosolization and generation of bioaerosols. The process depends on a number of parameters of the gas and liquid involved. This project investigated the influence of the air flow, bubble size, the temperature of the liquid and its surface tension on the efficiency of bioaerosol generation. It was found that the bioaerosol is more efficiently produced at higher air flow rates and smaller bubble size. The influence of the liquid temperature was also identified to be quite high, reaching an order of magnitude of the bioaerosol concentration over the temperature range from 4 °C to 38 °C. The addition of surfactants did suppress the foam formation, which was found to have a negative effect on the process; the rate of the bioaerosol generation increased with the increase in the antifoam concentration.

Benchmarking of different microbes for their biosurfactants antifungal action against plant pathogens

The biotic stress caused by phytopathogens (bacteria, fungus, yeast and insect pests) is a primary factor in yield loss of plants. Biocontrol agents and their active compounds are used to manage such plant pathogens. Here, in our study, we screened four bacterial isolates identified as Bacillus cereus, B. anthracis, B. velezensis and Serratia marcescens after morphological, biochemical and molecular characterization (16s rDNA sequencing) for production of biosurfactant by foam forming activity, oil spreading tests and emulsification activity. Highest foam stability (75 min) and maximum emulsification activity E24% (75%) was observed by B. velezensis strain. Among all the four isolates, Bacillus velezensis strain produced maximum biosurfactant (0.349±0.004 g/50 mL). Biosurfactant of all the four bacterial isolates were checked for fungal inhibiton on PDA plate(s). Bacillus velezensis showed comparatively the highest percent inhibition 58.82, 88.15, 78.45,72.68, 83.96, 75.47, 68.07 and 88.44% against Colletotrichum falcatum, Fusarium oxysporum f sp. ciceri, Helminthosporium maydis, F. oxysporum f. sp. lycopersici, Aspergillus niger, Mucor sp., Helminthosporium oryzae and Rhizoctonia solani, respectively. Bacillus velezensis biosurfactant among all the four bacterial isolates was found to be most effective against the tested phytopathogens.

Immobilization of Lipoxygenase, Catalase, and Lipase for a Reactor Design Targeting Linoleic Acid Hydroperoxidation

AbstractHydroperoxy‐9Z,11E‐octadecadienoic acid (13‐HPODE) can be obtained from safflower oil in an enzyme cascade utilizing lipase, lipoxygenase (LOX), and catalase for in situ oxygen generation. The application of immobilized enzymes may open a new path to a cost‐efficient production of 13‐HPODE, which is used for the synthesis of green note aroma hexanal. Ten immobilization supports are compared for immobilization of lipoxygenase‐1 from Glycine max (LOX‐1) and oxirane‐based Immobead 150 P proves to be best with a maximum LOX‐1 activity of 22 470 U g−1. The immobilizate is successfully recycled in eight consecutive batches and maintains full activity over a period of 16 h using a 3D‐printed column reactor. Catalase from Micrococcus lysodeikticus and LOX‐1 are co‐immobilized on Immobead 150 P allowing a constant production of 13‐HPODE for up to six cycles with a maximum product conversion of 45% and a 13‐regioselectivity of 83% . In this two‐enzyme system with H2O2‐dosage, foam generation is significantly reduced. Co‐immobilization of LOX‐1 and lipaseis possible; however, rapid lipase deactivation occurs. Therefore, a two‐reactor approach with oil hydrolysis in the first reactor is proposed. Immobilized lipases from C. rugosa are suitable for safflower oil hydrolysis and maintain full activity over ten hydrolysis cycles.Practical applications: Linoleic acid hydroperoxide (13‐HPODE) is the starting material for the synthesis of the green note aroma compound hexanal. The byproduct of the hydroperoxide splitting is ω‐oxododecenoic acid, which is currently not employed industrially. The bifunctional oxodocecenoic acid is interesting as precursor for the synthesis of polymer building blocks. Simple one‐step derivatization of the oxo‐group can yield suitable C12 monomers such as dicarboxylic acids, ω‐amino acids, or ω‐hydroxy acids. Cost‐efficiency is a key parameter to incorporate these new biobased building blocks for polymer applications. In this approach, immobilized enzymes are used for the synthesis of 13‐HPODE starting from safflower oil with in situ oxygen generation to prevent excessive foam formation. A two‐reactor concept is designed to circumvent hydroperoxide‐induced lipase deactivation. Direct comparison of both batch and continuous process is performed and provides information for the implementation of the enzyme cascade and the design of an optimized reactor system.

Facile Synthesis of Formaldehyde-Free Bio-Based Thermoset Resins for Fabrication of Highly Efficient Foams

Bio-based biodegradable foams were formulated from a crosslinkable network structure combining starch, furfuryl alcohol, glyoxal, and condensed tannin in the presence of p-toluenesulfonic acid (pTSA) and azodicarbonamide (AC) as a foaming agent. More importantly, the reinforcement of gelatinized starch-furanic foam using tannin, originating from forestry, resulted in an excellent compressive strength and lower pulverization ratio. Moreover, the addition of tannin guaranteed a low thermal conductivity and moderate flame retardancy. Fourier transform infrared (FTIR) spectroscopy approved the successful polycondensation of these condensing agents under the employed acidic conditions. Moreover, the catalytic effect of pTSA on the foaming agent induced liberation of gases, which are necessary for foam formation during crosslinking. Scanning electron microscopy (SEM) showed foam formation comprising closed cells with uniform cell distribution and appropriate apparent density. Meanwhile, the novel foam exhibited biodegradation under the action of Penicillium sp., as identified by the damage of cell walls of this foam over a period of 30 days.

Foam-in-Vein: Characterisation of Blood Displacement Efficacy of Liquid Sclerosing Foams.

Sclerotherapy is among the least invasive and most commonly utilised treatment options for varicose veins. Nonetheless, it does not cure varicosities permanently and recurrence rates are of up to 64%. Although sclerosing foams have been extensively characterised with respect to their bench-top properties, such as bubble size distribution and half-life, little is known about their flow behaviour within the venous environment during treatment. Additionally, current methods of foam characterisation do not recapitulate the end-point administration conditions, hindering optimisation of therapeutic efficacy. Here, a therapeutically relevant apparatus has been used to obtain a clinically relevant rheological model of sclerosing foams. This model was then correlated with a therapeutically applicable parameter-i.e., the capability of foams to displace blood within a vein. A pipe viscometry apparatus was employed to obtain a rheological model of 1% polidocanol foams across shear rates of 6 s-1 to 400 s-1. Two different foam formulation techniques (double syringe system and Tessari) and three liquid-to-gas ratios (1:3, 1:4 and 1:5) were investigated. A power-law model was employed on the rheological data to obtain the apparent viscosity of foams. In a separate experiment, a finite volume of foam was injected into a PTFE tube to displace a blood surrogate solution (0.2% w/v carboxymethyl cellulose). The displaced blood surrogate was collected, weighed, and correlated with foam's apparent viscosity. Results showed a decreasing displacement efficacy with foam dryness and injection flowrate. Furthermore, an asymptotic model was formulated that may be used to predict the extent of blood displacement for a given foam formulation and volume. The developed model could guide clinicians in their selection of a foam formulation that exhibits the greatest blood displacement efficacy.

Potent Application of Scrap from the Modified Natural Rubber Production as Oil Absorbent

The production of raw natural rubber always ends up with leftover latex. This latex is later collected to produce low grades of rubber. The collection of this latex also depends on the latex's quality. However, reproducing the latex may not be applicable if the latex contains many specks of dirt which will eventually be discarded. In this work, an alternative solution was to utilize such rubber in a processable form. This scrap rubber (SR) from the production of natural rubber grafted with polymethyl methacrylate (NR-g-PMMA) production was recovered to prepare an oil-swellable rubber. The rubber blends were turned into cellular structures to increase the oil swellability. To find the suitable formulation and cellular structure of the foam, the foams were prepared by blending SR with virgin natural rubber (NR) at various ratios, namely 0/100, 20/80, 30/70, 50/50, 70/30, 80/20, and 100/0 (phr/phr). The foam formation strongly depended on the SR, as it prevented gas penetration throughout the matrix. Consequently, small cells and thick cell walls were observed. This structure reduced the oil swellability from 7.09 g/g to 5.02 g/g. However, it is interesting to highlight that the thermal stability of the foam increased over the addition of SR, which is likely due to the higher thermal stability of the NR-g-PMMA waste or SR. In summary, the blending NR with 30 phr of SR provided good oil swellability, processability, and morphology, which benefit oil recovery application. The results obtained from this study will be used for further experiments on the enhancement of oil absorbency by applying other key factors. This work is considered a good initiative for preparing the oil-absorbent material based on scrap from modified natural rubber production.

Foaming and Physicochemical Properties of Commercial Protein Ingredients Used for Infant Formula Formulation.

Protein, as one of the main ingredients for infant formula, may be closely related to the undesirable foam formed during the reconstitution of infant formula. Demineralized whey powder (D70 and D90), whey protein concentrate (WPC), and skimmed milk powder (SMP) are the four protein ingredients commonly used in infant formula formulation. The foaming and physicochemical properties of these four protein ingredients from different manufacturers were analyzed in the present study. Significant differences (p < 0.05) in foaming properties were found between the samples from different manufacturers. SMP showed a highest foaming capacity (FC) and foam stability (FS), followed by D70, D90, and WPC. Although the protein composition was similar based on reducing SDS-PAGE, the aggregates varied based on non-reducing SDS-PAGE, probably resulting in the different foaming properties. Particle size, zeta potential, and solubility of the protein ingredients were assessed. The protein structure was evaluated by circular dichroism, surface hydrophobicity, and free sulfhydryl. Pearson's correlation analysis demonstrated that FC and FS were positively correlated with random coil (0.55 and 0.74), β-turn (0.53 and 0.73), and zeta potential (0.55 and 0.51) but negatively correlated with β-strand (-0.56 and -0.71), free sulfhydryl (-0.56 and -0.63), particle size (-0.45 and -0.53), and fat content (-0.50 and -0.49). The results of this study could provide a theoretical guidance for reducing formation of foam of infant formula products during reconstitution.

Liquid Foaming Agent for Liquid Loading Reduction in Gas Producing Wells

The main objective of this research was to develop a liquid foaming agent for optimizing gas production in wells belonging to the Santa Rosa field in Área Mayor de Anaco, Venezuela. In this research, three liquid foaming agent formulations were developed with an anionic and amphoteric surfactants mixture, performing tests to evaluate foaming and lifetime on samples with different produced water/hydrocarbon condensate ratios. A liquid drag test was also carried out, explaining the liquid recovery performance after applying the developed formulations at different dosages and finally evaluated products results were compared with a commercial one. Formulation 1 obtained a higher liquid recovery compared to the other formulations, in addition, recovered liquid amount in dynamic drag tests decreased as the condensates composition increased in four samples evaluated. Formulation 1 and commercial product used as a reference did not have statistically significant differences.