Cream Layer Research Articles

SEM-Guided Finite Element Simulation of Thermal Stresses in Multilayered Suspension Plasma-Sprayed TBCs

This study presents novel insights into thermal stress development and crack propagation mechanisms in single- and multilayered suspension plasma-sprayed (SPS) coatings of gadolinium zirconate (GZ) and yttria-stabilized zirconia (YSZ), thermally treated at 1150 °C. By combining image processing with finite element simulation, we pinpointed sites of high-stress concentration in the coatings, leading to specific cracking patterns. Our findings reveal a dynamic shift in the location of stress concentration from intercolumnar gaps to pores near the top coat/thermally grown oxide (TGO) interface with TGO thickening at elevated temperatures, promoting horizontal crack development across the ceramic layers. Significantly, the interface between the ceramic layer and TGO was found to be a critical area, experiencing the highest levels of both normal and shear stresses. These stresses influence failure modes: in double-layer SPS structures, relatively higher shear stresses can result in mode II failure, while in single-layer systems, the predominant normal stresses tend to cause mode I failure. Understanding stress behavior and failure mechanisms is essential for enhancing the durability of thermal barrier coatings (TBCs) in high-temperature applications. Therefore, by controlling the interfaces’ roughness along with improving interfacial toughness, the initiation and propagation of cracks can be delayed along these interfaces. Moreover, efforts to optimize the level of microstructural discontinuities, such as intercolumnar gaps and pores, within the creaming layer and close to the TGO interface should be undertaken to reduce crack formation in the TBC system.

Novel concentrated O/W emulsion co-stabilized by like-charged chitosan nanoparticle and ethyl lauroyl arginate (LAE) surfactant at very low dosages

Emulsions co-stabilized by like-charged cationic ethyl lauroyl arginate (LAE) and positively charged chitosan/sodium tripolyphosphate (CS-TPP) nanoparticles at low doses were prepared. The effects of CS-TPP nanoparticle concentration, LAE concentration, and pH on storage stability and mean droplet diameter were investigated, and the emulsion microstructure was examined by confocal laser scanning microscopy. The emulsions formed by LAE and CS-TPP were O/W emulsions, different from W/O emulsions formed by CS-TPP alone. The stability of the emulsions co-stabilized by LAE and CS-TPP was superior to that of the emulsions stabilized by LAE alone or CS-TPP nanoparticles alone. The emulsions could maintain good stability with 0.5 mM LAE and 0.08 wt% CS-TPP at pH ranging from 3.5 to 5.5. After standing and layering, the upper cream layer of CS-TPP+LAE emulsions could form stable high internal phase emulsions. For the novel emulsion, LAE dominated the formation of emulsion droplets, and adsorbed CS-TPP nanoparticles played a crucial role in the emulsion stability. The adsorbed CS-TPP nanoparticles discretely attached to oil droplets could form a strawberry-like construct, which could prevent the coalescence of emulsion droplets through electrostatic repulsion and steric hindrance. This work demonstrates the capacity of low dose food-grade emulsifiers and stabilizers to form stable emulsions.

Biorefining of liquid insect fractions by microfiltration to increase functionality

Insects are gaining attention as sustainable protein sources, necessitating the evaluation of gentle processing techniques for decontamination and fractionation of edible insects. Microfiltration was shown to be an effective alternative to thermal treatments for microbial decontamination of soluble insect protein. In this study, mealworm and cricket fractions extracted at pH 3 and 8, obtained through a microfiltration (0.2 μm polyethersulphone membrane) process, were assessed. This microfiltration process yielded a cream layer, a retentate containing protein aggregates, and a decontaminated permeate containing smaller-sized proteins (mostly <75 kDa). Microfiltration improved the permeates’ foamability to values higher than whey protein isolate (215–317% vs. 163%), while the retentates retained the gelling properties of up to ≈5000 Pa. Additionally, stable lipid droplets resembling plant-based oleosomes were recovered from the cream layer. This study shows that microfiltration is promising for simultaneous decontamination and fractionation, providing distinct fractions for diverse food applications.

Diagnostic Evaluation of the IS1081-Targeted Real-Time PCR for Detection of Mycobacterium bovis DNA in Bovine Milk Samples.

The ability of Mycobacterium bovis (M. bovis) to survive in bovine milk has emerged as a serious public health concern. The first objective of this study was to evaluate the diagnostic utility of IS1081-targeted real-time PCR for the detection of M. bovis DNA in different fractions of bovine milk. In a model study, bovine milk samples were spiked with serially diluted M. bovis BCG to investigate the detection limit of M. bovis DNA in whole milk and milk fractions (cream, pellet, and pellet + cream combined) using IS1081 real-time PCR. The assay was then used to detect M. bovis DNA in whole milk and milk fractions from naturally infected animals. The results showed that the IS1081 real-time PCR was more sensitive when detecting M. bovis DNA in the cream layer alone and cream + pellet combined compared to whole milk or the pellet alone. While PCR-based diagnostic assays for the detection of M. bovis in milk samples provide a quicker diagnostic tool for bovine tuberculosis, safe processing, and handling of M. bovis-infected milk samples remain a challenge and pose a human health risk. PrimeStore Molecular Transport Medium (MTM) has been shown to rapidly inactivate infected specimens while preserving nucleic acid for subsequent Molecular analysis. Therefore, the secondary objective of this study was to evaluate the ability of MTM to inactivate M. bovis BCG in spiked milk samples as well as its ability to preserve BCG DNA for the PCR assay. The results showed that MTM can successfully inactivate BCG alone or in spiked milk samples while preserving DNA for the PCR assay. The CT values of M. bovis BCG alone and spiked milk samples aliquoted in MTM and without MTM were similar at various dilutions. Taken together, our results indicate that using DNA extracted from the milk cream fraction alone or combined milk cream and pellet improved the recovery rate of M. bovis DNA in bovine milk samples. MTM has the potential to provide a safe and rapid sample processing tool for M. bovis inactivation in milk samples and preserve DNA for molecular diagnostics.

Reduced skin permeation and penetration of clobetasol propionate when Dermovate cream is applied at short time intervals with emollients

AbstractBackgroundDermovate cream containing 0.05% clobetasol propionate is a very potent topical corticosteroid (TCS) used in the treatment of severe inflammatory dermatoses. Regular emollient therapy should continue alongside clobetasol propionate treatment, however, the impact on drug delivery to the skin when both products are applied at similar times is unknown.ObjectivesTo assess whether application of emollients at similar times to Dermovate cream alter the delivery of clobetasol propionate to the skin.MethodsThis study was conducted using ex vivo human skin mounted in Franz cells. Dermovate cream was applied before or after three different emollients, Hydromol Intensive cream, Doublebase gel, and Diprobase ointment at 5‐ or 30‐min intervals. Drug delivery to the skin was assessed up to 24 h using high‐performance liquid chromatography.ResultsSignificantly reduced clobetasol propionate delivery to the skin was observed when Dermovate cream was applied either before or after the three different emollients, compared to the application of Dermovate cream alone. The data suggest in situ formation of a mixed Dermovate cream and emollient layer which reduces clobetasol propionate delivery relative to the original product. Applying Dermovate cream after any emollient generally resulted in larger reductions in drug delivery to the skin, compared to when the steroid was applied first. This was attributed to the emollients forming an additional barrier to drug delivery at the skin‐formulation interface.ConclusionsThese findings indicate that applying Dermovate cream at similar times as emollients can significantly reduce drug delivery to the skin and that separating the application of the two products by intervals of up to 30 min is not sufficient to mitigate this effect.

Resistive Switching Property of Raw Organic Cow Milk for Memory Application

Organic material-based computer memory devices are critical for lowering the amount of electronic waste. Toward this end, we here present the resistive switching property of metal-insulator-metal type devices consisting of active layers made of raw organic cow milk. Our devices were made up of fat-free, medium cream, and full cream raw cow milk active layers sandwiched between indium-doped tin oxide and silver electrodes. These devices were created without the use of heat or electricity, and because they use cow milk as their active layers, they do not pollute the environment. The medium-fat milk film had a higher weight percentage of metallic ions than the fat-free and full-cream milk films, according to energy-dispersive X-ray spectroscopy analysis of the active layers. As a result, electrical characterization and memory studies revealed that conductive filaments driven by a space-charge-limited conduction mechanism were responsible for the “S-type” memory characteristics of the medium-fat milk-based device, with switching at remarkably low VSET=+0.48V and VRESET=−0.25V. Furthermore, with over 30 write/erase cycles, this device demonstrated better non-volatile computer memory device prospects. Hoping conduction-driven conductive filaments, on the other hand, were linked to the behavior of devices that use fat-free and full-cream milk. Overall, our findings show that the fat and ion content of milk plays an important role in the morphology, transport, and switching of these devices.

Fabrication of dual-functional cellulose nanocrystals/fluorinated polyacrylate containing coumarin derivatives by RAFT-assisted Pickering emulsion polymerization for self-healing application

Polymeric coatings are easy to be damaged by harsh environment condition, which causes cracks and loss of function. Inspired by the natural self-healing phenomenon, we successfully synthesized dual-functional cellulose nanocrystals/fluorinated polyacrylate containing coumarin derivatives by RAFT-assisted Pickering emulsion polymerization. The amphiphilic and photo-responsive copolymer, PDMAEMA-b-PGMA-b-P(HFBA-co-VBMC) was synthesized by RAFT process, followed by characterization using FT-IR, SEC, 1H NMR and UV–vis. The cellulose nanocrystals were modified by the copolymer, which were confirmed via XPS, UV–vis and so on. Besides, the droplet size of Pickering emulsion gradually increased and the creaming layer gradually decreased as the pH value increased. The TEM result showed that the modified cellulose nanocrystals were effectively anchored on the outside of latex particles. The size of the spherical-like latex particles increased and the stability of latex particles was worse with increasing pH value. Finally, the finished fabric had excellent water resistance due to the combination of micro- or nanoscale hierarchical structure and low surface energy. Moreover, the latex film exhibited excellent repeatability of self-healing ability. The fabric coating achieved the intrinsic and superficial dual-functional self-healing performance by the reversible [2 + 2] cycloaddition of coumarin groups. This strategy provides a powerful guide for preparing the high-performance waterborne fluorinated polyacrylate coating.

Strain- and serotype-dependent affinity of Shiga toxin-producing Escherichia coli for bovine milk fat globules.

Shiga toxin-producing Escherichia coli (STEC) are widely detected in raw milk products intended for human consumption. Although STEC are a worldwide public health problem, the pathogenicity of STEC in cheese remains unclear. In fact, bacterial association with compounds in raw milk cheeses could reduce their pathogenicity. A previous study showed the association of 2 STEC strains with raw milk cream in a natural creaming assay. Different concentrations of each strain were required to saturate the cream. In this study, we hypothesized that all STEC strains could be associated with milk fat globules (MFG) in raw milk and that the bacterial load required for saturation of the cream is serotype dependent. We evaluated the affinity of STEC strains belonging to the O157:H7, O26:H11, and O103:H2 serotypes for bovine raw milk cream and analyzed saturation of the cream layer by natural creaming assay. We used 12 STEC strains and 3 strains belonging to another pathotype to assess the effects of serotypes on this phenomenon. We performed sucrose density gradient centrifugation assays with 2 STEC model strains to confirm the results obtained by natural creaming. The localization of STEC within MFG-enriched creams was observed by confocal and electron microscopy. We recovered approximately 10 times more STEC from the cream layer after natural creaming than from raw bovine milk. The concentration of STEC required to saturate the cream layer (the saturation concentration) was estimated for each strain by nonlinear regression, highlighting a strain and serotype effect. Moreover, the concentration of STEC in the cream was milk fat level dependent. However, even in nonsaturating conditions, a high level of STEC was still present in the aqueous phase, after fat separation. Thus, natural creaming should not be used as the sole preventive measure to remove STEC from naturally contaminated raw milk. The results of our study suggest that cream saturation is a complex mechanism, most likely involving specific interactions between STEC and raw MFG.

Modified cotton fabric with durable anti-fouling performance for separation of surfactant-stabilized oil-in-water emulsions

Membrane applications for the separation of surfactant-stabilized emulsions are often constrained by a deficiency in permeability and anti-fouling properties. Herein, special wetted cotton fabric with a protective layer (P-MH@CF) for durable anti-fouling performance was synthesized by a two-step method, which was related to interfacial ion migration technology and unilateral spraying treatment. Permeability of water and separation performance of P-MH@CF membrane were investigated systematically. Emulsions stabilized by anionic, cationic, or non-ionic surfactant were successfully separated with high efficiency. In the process of separation, the oil droplets surrounded by surfactants were difficult to demulsify and gathered physically on the membrane surface to form a “cream layer”. The stearic acid acted as a protective layer, like a quilt, protecting the membrane from contamination. The membrane retained robust reusability for separation even after the “cream layer” had been washed off, which was promising for the remediation of oily wastewater containing surfactants.

Plant-Based Milks: Alternatives to the Manufacture and Characterization of Ice Cream

This study investigated the potential use of dietary fibers (psyllium and pectin fibers added in different proportions of 0–10%) to improve the rheological, textural, and sensory characteristics of vegetable ice cream using vegetable milk (almond and hemp milk). Hemp milk was obtained from the peeled seeds of the industrial hemp plant, which includes varieties of Cannabis sativa, which have a low content of the psychotropic substance tetrahydrocannabinol (THC) and are grown for food. The rheological characteristics of the mix and ice cream were determined by using the Haake Mars rheometer. Compared with the control sample, the viscosities of the mix in all samples analyzed were enhanced with the addition of dietary fibers, due to the occurrence of interactions and stabilizations. The viscoelastic modules G′ G″ were determined on ice cream samples at a temperature of −10 °C. The elastic and viscous modulus showed high values with the increase of the addition of 6% dietary fibers. The textural characteristics were assessed by the shear strength of a layer of ice cream at a temperature of −4 °C. Hardness, firmness, and adhesiveness were influenced by the size of their ice crystals, the fat content, and the percentage of dietary fibers added. The sensory analysis of the ice cream showed higher overall scores for the almond milk ice cream, because the sweet taste was appreciated with a maximum score, while the hemp milk ice cream was evaluated for flavor and taste.

Creaming Layers of Nanocellulose Stabilized Water-Based Polystyrene: High-Solids Emulsions for 3D Printing

Oil-in-water emulsions stabilized using cellulose nanofibrils (CNF) form extremely stable and high-volume creaming layers which do not coalesce over extended periods of time. The stability is a result of the synergistic action of Pickering stabilization and the formation of a CNF percolation network in the continuous phase. The use of methyl cellulose (MC) as a co-emulsifier together with CNF further increases the viscosity of the system and is known to affect the droplet size distribution of the formed emulsion. Here, we utilize these highly stable creaming layer systems for in situ polymerization of styrene with the aim to prepare an emulsion-based dope for additive manufacturing. We show that the approach exploiting the creaming layer enables the effortless water removal yielding a paste-like material consisting of polystyrene beads decorated with CNF and MC. Further, we report comprehensive characterization that reveals the properties and the performance of the creaming layer. Solid-state NMR measurements confirmed the successful polymerization taking place inside the nanocellulosic network, and size exclusion chromatography revealed average molecular weight (Mw) of polystyrene as approximately 700,000 Da. Moreover, the amount of the leftover monomer was found to be less than 1% as detected by gas chromatography. The dry solids content of the paste was ∼20% which is a significant increase compared to the solids content of the original CNF dispersion (1.7 wt%). The shrinkage of the CNF, MC and polystyrene structures upon drying—an often-faced challenge—was found to be acceptable for this composite containing highly hygroscopic biobased materials. At best, the two dimensional shrinkage was no more than ca. 20% which is significantly lower than the shrinkage of pure CNF being as high as 50%. The paste, which is a composite of biobased materials and a synthetic polymer, was demonstrated in direct-ink-writing to print small objects. With further optimization of the formulation, we find the emulsion templating approach as a promising route to prepare composite materials.

Effect of high-pressure homogenization on structural changes and emulsifying properties of chicken liver proteins isolated by isoelectric solubilization/precipitation

This study investigated the effect of high-pressure homogenization (HPH) (0, 20, 40 and 60 MPa) on the emulsifying properties and structural changes of chicken liver (CL) proteins isolated by isoelectric solubilization/precipitation (ISP) (with the acid/alkaline solubilization at pH 2.0, pH 3.0, pH 11.0 and pH 12.0 respectively and the precipitation at pH 5.5). Results showed that HPH could significantly decrease the particle size. With the increase of homogenization pressure, the solubility of the same ISP-isolated CL-proteins increased significantly and that of alkali-isolated proteins was the highest (P < 0.05). The preferable emulsifying activity index (EAI) and emulsifying stability index (ESI) were obtained at pH 11.0 after 40 MPa treatment (reaching 34.90 m2/g and 37.77% respectively), which appeared the highest creaming layer. Compared with other treatments, the corresponding same ISP-isolated CL-proteins at 40 MPa HPH had highest surface hydrophobicity index (H0) and free sulfhydryl content. After HPH, Raman spectroscopy revealed that the same ISP-isolated CL-proteins presented a decrease in α-helix accompanied by the increase of the β-sheet to be beneficial to the formation of stable emulsion. This study showed that suitable HPH combined with ISP treatments promoted the emulsifying stability of proteins.

The Effect of High-Pressure Treatment and Skimming on Caprine Milk Proteins

Background: Proteins are susceptible to HP-treatment and there is a need to determine the applicability of HP-treatment in dairy production. The aim of this study was to determine the effect of HP-treatment at 200–500 MPa (tconst. = 10 min; Tconst. = 20 °C) and skimming of HP-treated milk on the content of nitrogen compounds and protein composition of caprine milk. Methods: The content of nitrogen (total, non-casein, non-protein) was determined using the Kjeldahl method. Casein fractions and whey proteins were separated using SDS-PAGE electrophoresis. Color parameters were measured in the CIELAB color space. Results: HP-treatment decreased (p &lt; 0.05) the content of non-casein nitrogen and soluble whey proteins. Skimming decreased the content of nitrogen compounds, and the noted decrease was more pronounced in HP-treated milk. Pressure and skimming had no influence on the proportions of α-, β-, κ-casein, β-lactoglobulin and α-lactalbumin. Total color difference (ΔE) increased with a rise in pressure, particularly in skim milk. Conclusion: HP-treatment led to a loss of protein solubility at pH 4.6 in caprine milk. In HP-treated milk, skimming did not induce changes in protein composition, despite a decrease in the content of nitrogen compounds after the separation of the cream layer. Higher values of ΔE in skim milk than in whole milk point to changes in colloidal phase components.

Ultrasonic assisted oil-in-water emulsions stabilized by flaxseed protein isolate: influence of different oils

In this study, the physicochemical properties and stability of ultrasonic assisted flaxseed protein isolates (FPI) emulsions containing medium chain triglycerides (MCT), soybean oil, flaxseed oil, or docosahexaenoic acid (DHA) algae oil were investigated. The particle size distribution, zeta-potential, turbiscan stability index (TSI), and backscattering profiles were determined. The results showed that the emulsions containing flaxseed oil had the smallest droplet size and the lowest TSI value after 30 min ultrasonic treatment. Flaxseed oil emulsions showed the best storage stability with minimum clarified layer and cream layer after 10 days storage. MCT emulsions were more sensitive to salt, and less stable than other oil emulsions. Soybean oil, flaxseed oil, and DHA oil emulsions had good stability under low ionic strengths (0–50 mM NaCl), and became unstable under high ionic strengths (150 and 300 mM). Thermal treatment had great influence on the particle size distribution of emulsions. The particle size of the four oils emulsions increased after heating at 90 °C for 30 min. However, the particle size of DHA oil and flaxseed oil emulsions decreased after heating at 50 °C for 30 min. In conclusion, ultrasonic treatment is one of the effective ways to improve stability of FPI-stabilized emulsions, which are based on the oil type and ultrasound intensity. The effects of oil type and chain length on particle size and stability of FPI-stabilized emulsions could be further studied.

Physico-chemical and sensory acceptance of Carica papaya leaves extract edible O/W emulsion as prospective natural remedies

Carica papaya Linnaeus commonly known as papaya is widely grown in Malaysia as a herbaceous plant with phytochemicals for a variety of use, particularly in the medical field. The therapeutic medicinal way of treating dengue fever using papaya leave extract mainly involves consumption a raw concoction and is very distasteful. Therefore, a study was carried out to develop stable emulsion with an acceptable taste through a ternary phase diagram system (TPDS), which comprised virgin coconut oil (VCO), isolated whey protein (WPI) and Carica papaya leaves extract (CPLE). The TPDS was developed using Chemix Software version 3.6 to identify the existence of homogenous phase region. In the first phase, a total of 11 selected samples (named as A to K) with concentrations ranging from 20% to 30% (w/w) of WPI from the homogenous phase region were used to select the best emulsion selection. Sample I with a composition of 25, 30 and 45% (w/w) comprising VCO, WPI and CPLE was selected and considered as the best and stable emulsion. In the second phase, sample I (renamed as sample M) underwent an addition of + 2% (sample L) and reduction of −2% (sample N) VCO. Analysis was carried out such as emulsion stability test (creaming index), pH value, viscosity, color and storage stability (4, 28 and 45 °C). The control sample was CPLE without any VCO or WPI. Sensory evaluation was also conducted to handpick the best formulation favored by 30 panellists. The sensory evaluation was conducted on samples L, M, N and CPLE using 7-point hedonic scale for preference on color, viscosity, odor, bitterness and overall acceptance attributes. The results showed that centrifugation test exhibited a stable emulsion for all the three samples (p > 0.05) L, M and N. In fact, there were differences between all the samples (p < 0.05) for pH, viscosity, and coloration of L* and b* values. For the storage stability test, all formulations were stable at 4 °C and there were no creaming layer and color changes developed except for sample L which was considered unstable at 28 °C and 45 °C. As for sensory preference, the color and bitterness was considered similar as compared to control (p < 0.05) except viscosity, odour and overall acceptance. In conclusion, sample N with compositional concentrations of 23% (w/w) VCO, 32% (w/w) WPI and 45% (w/w) CPLE was considered the most acceptable emulsion as it did not develop immiscible creaming layer and color changes at 4 °C and 28 °C. Based on the selected formulation, at least 270 ml emulsion by taking 3 tablespoons daily for 3 days in a row is needed as recommended by the Ministry of Health (MOH) in helping to increase the chances of curing dengue fever.

Sodium hexametaphosphate’s impact on hydrodynamic parameters of milk fat globule membrane

Being able to stabilise milk fat globule particles after pasteurisation over time and reduce the phase separation and migration rate of the cream layer would be of great interest. This study examined the prolonged destabilisation of MFGM emulsions after blending with sodium hexametaphosphate (SHMP) with respect to particle migration, fat globule size distribution, phase separation, variations in the raw signal and serum‐phase protein levels. Low SHMP levels in blended MFGM reduced the interactions between fat droplets during heating. Low SHMP concentrations are recommended for stabilising MFGM.

Mechanical and Enzyme Assisted Fractionation Process for a Sustainable Production of Black Soldier Fly (Hermetia illucens) Ingredients

This study aimed at effective fractionation of Hermetia illucens into lipid and protein, taking into account the insects’ anatomy. A hybrid approach was developed, separating the exoskeleton by mechanical pressing and fractionating the slurry by sonication and enzymatic treatment. Microscopy showed the peripheral fat bodies were tightly attached to muscle fibers. Blanching caused protein aggregation and entrapment of fat in the protein matrix, resulting in 25.0% loss in fat extraction, compared to only 3.3% loss for unblanched larvae. After centrifugation of the juice obtained from unblanched larvae a cream layer rich of lipids and proteins, a supernatant with soluble protein, and a pellet including mainly insoluble protein were obtained. Blanched juice centrifugation formed a lipid fraction, a reduced cream layer, and more pellet. Whereas sonication hardly affected the fractionation, enzymatic treatment resulted in solubilisation of pellet protein and an increased lipid layer. Absence of blanching is very effective to extract more lipids (>80%) from whole larvae in the form of a cream layer, while blanched-enzymatic treatment extracted most lipids in a clear lipid layer (>40%). For all treatments around 50% of protein was recovered in the residue and the other 50% mainly in the pellet after centrifugation.

Southern-style Pad Thai sauce: From traditional culinary treat to convenience food in retortable pouches.

Pad Thai, a Thai dish of stir-fried rice noodles and other ingredients, is one of the culinary heritages of Thailand. In the southern region of Thailand, Pad Thai has different characteristics from other areas because coconut milk and curry paste are used to produce a thick sauce prior to cooking. To commercially distribute this uniquely local culinary treat in a convenient form all over Thailand and other export markets, a shelf-stable sauce using heat sterilization should be developed. Retort processing technology with retort pouches can be used for this purpose. However, phase separation and lipid oxidation can occur and subsequently reduce the overall quality of retorted southern-style Pad Thai sauce. The application of an appropriate stabilizer and antioxidant can be used to prevent such problems. Thus, the objective of this study was to investigate the effects of stabilizers and antioxidants on the stability of retorted southern-style Pad Thai sauce. Southern-style Pad Thai sauce was prepared according to the traditional recipe in the presence of different stabilizers (2.3% potato starch (PS) + 0.1% xanthan gum (XG), 0.5% soy lecithin (LT), and 4% whey protein isolate (WPI)) and antioxidants (500 mg/kg ascorbyl palmitate + 500 mg/kg α-tocopherol (As + Toc), 100 mg/kg ethylenediaminetetraacetic acid (EDTA), 200 mg/kg butylated hydroxytoluene (BHT), and As+Toc+EDTA+BHT (mixed antioxidants)). Samples were packed in retort pouches and processed in a retort at 121°C with an F0 value of 3.57 min. Results showed that the retorted southern-style Pad Thai sauce can be stabilized by 2.3% PS plus 0.1% XG in combination with mixed antioxidants. PS and XG helped stabilize the sauce with a desirable viscosity, water holding capacity, and color without any creaming layer and negative effect on sensory properties. Mixed antioxidants improved the oxidative stability of the retorted sauce by retarding the changes in the peroxide value and color during retorting. Consequently, the processing of southern-style Pad Thai sauce in retortable pouches could increase the market demand for this traditional product due to its convenience and ready-to-use features.

Addition of cationic guar-gum and oleic acid improved the stability of plasma emulsions prepared with enzymatically hydrolyzed egg yolk

The plasma, which is an effective contributor to the emulsifying properties of egg yolk, could offer new pathways in emulsification technology. This study investigated the influence of cationic guar gum (CGG) and oleic acid (OA) on the emulsion stability of the subtilisin-hydrolyzed natural plasma (NP). The results showed that the enzyme-hydrolyzed plasma (EP) contributed to the higher ζ-potential, smaller D[4,3] and lower initial interface tension of the droplets than the NP, which improved emulsion stability. The enzymatic hydrolysis of plasma enhanced the electrostatic repulsions of the droplets and accelerated the adsorption of proteins at the interface. As the addition of CGG increased from 0.020% to 0.040% (w/v), the EP droplets with higher ζ-potential and smaller D[4,3] were formed because of the interactions between the interface membrane. The addition of CGG at 0.030% (w/v) significantly increased the emulsifying stability index of the EP (from 22.9 to 55.4). After 375 min of holding, the cream layer decreased from 68% to 58% when 0.040% (w/v) CGG and 1% (v/v) OA were added to the emulsion. These results confirmed that the EP with CGG and OA enhanced the viscosity and the weak-gel structure, which improved the stability of the emulsion.

Effect of acidic moisture-conditioning as pretreatment for aqueous extraction of flaxseed oil with lower water consumption

Acidic moisture-conditioning plus low temperature drying (AMCLTD) was applied as a pretreatment on flaxseed kernel, for the first time, prior to aqueous extraction (AEP) of flaxseed oil with lower water consumption. Limited information is available on how different pretreatments affect the free oil recovery during AEP. The use of AMCLTD pretreatment with 0.3 M citric acid and drying at 70 °C for 1 h resulted in approximately 83.27 ± 0.67% free oil recovery with thinner cream layer than the sample without pretreatment. Confocal laser scanning microscopy and transmission electron microscopy observations reveal that the coalescence of oil bodies and shrinkage of protein bodies resulted in the decrease of cream and the increase of free oil from AEP. Interestingly, the lowest mean particle size of AMCLTD sample proved that this pretreatment was beneficial to flaxseed comminution. Moreover, the pretreatment showed no significant effect on the fatty acid composition and quality of flaxseed oil. These results demonstrated that AMCLTD pretreatment holds high potential for high-quality flaxseed oil extraction from AEP.