Legume milk-based yogurt mimetics structured using glucono-δ-lactone.

The potential to produce protein-structured vegan yogurts with legumes was explored to offer an alternative to conventional polysaccharide-based varieties. Glucono-δ-lactone (GDL) was employed as a slow acidifying agent and was investigated for its ability to generate cold-set, yogurt-like gels using soy and lentil milks made using minimal processing steps. Soy (5.3 % protein) and lentil (6.1 % protein) milks were successfully gelled by GDL at concentrations of 0.5 % and 1 % w/w. Soy and lentil milks experienced similar acidification profiles and demonstrated good fits with double-exponential decay models. The physical properties of these legume gels were evaluated and compared to a commercial stirred dairy yogurt. Penetration tests were carried out on intact gels, then repeated after stirring. All intact soy samples demonstrated significantly stronger gel structures compared to the commercial yogurt, and most experienced greater amounts of brittleness. Results showed that the stirring of gels caused a notable decrease in firmness and brittleness in the soy gels, making them more similar to the control. Power-law modelling of viscosity curves demonstrated that all samples experienced non-Newtonian flow behavior (n < 0.29). Susceptibility to syneresis was measured by the degree of liquid loss following centrifugation. The optimization of protein type and GDL concentration to replicate the physical properties of dairy-based yogurts can enhance their consumer acceptance and provide a more customizable and controlled approach alternative to traditional fermentation methods.

Oleosome interfacial engineering to enhance their functionality in foods.

This study aimed to increase the physical stability of native sunflower oleosomes to expand their range of applications in food. The first objective was to increase the stability and functionality of oleosomes to lower pH since most food products require a pH of 5.5 or lower for microbial stability. Native sunflower oleosomes had a pI of 6.2. One particularly effective strategy for long-term stabilization, both physical and microbial, was the addition of 40% (w/w) glycerol to the oleosomes plus homogenization, which decreased the pI to 5.3 as well as decreasing oleosome size, narrowing the size distribution and increasing colloidal stability. Interfacial engineering of oleosomes by coating them with lecithin and the polysaccharides xanthan and gellan, effectively increased stability, and lowered their pI to 3.0 for lecithin and lower than 3.0 for xanthan. Coating oleosomes also caused a greater absolute value of the ζ-potential; for example, this amount was shifted to -20 mV at pH 4.0 for xanthan and to -28 mV at pH 4.0 for lecithin, which provides electrostatic stabilization. Polysaccharides also provide steric stabilization, which is superior. A significant increase in the diameter of coated oleosomes was observed with lecithin, xanthan and gellan. The oleosome sample with 40% glycerol showed high storage stability at 4 °C (over three months). The addition of glycerol also decreased the water activity of the oleosome suspension to 0.85, which could prevent microbial growth.

Enzymatic glycerolysis for the conversion of plant oils into animal fat mimetics.

Substituting animal-based fats with plant-based fats of similar stability and functionality has always posed a significant challenge for the food industry. Enzymatic glycerolysis products are systems formed by converting native triacylglycerols in liquid oils into monoacylglycerols and diacylglycerols, mainly studied in the last few years for their unique structural ability. This study aims to modify and scale up the glycerolysis process of different plant oils, e.g., shea olein, palm olein, tigernut, peanut, cottonseed, and rice bran oils, with the goal of producing animal fat mimetics. The reactions were conducted at 65 °C, with a plant oil:glycerol molar ratio of 1:1, and without the addition of water, using a lab-scale reactor to convert up to 2 kg of oil into solid fat. Product characteristics were comparable at both laboratory and pilot plant scales, supporting the commercial viability of the process. Oil systems containing higher levels of both saturated and monounsaturated fatty acids, such as shea olein and palm olein, displayed higher solid fat content at elevated temperatures and broader melting profiles with significantly higher melting points. Comparison of the thermal softening behavior and mechanical properties of these systems with those of pork, beef, and lamb fat showed their high potential to replace adipose fat in the new generation of plant-based meat analogs.

Erratum: Removal notice to "Oleosome interfacial engineering to enhance their functionality in foods" [Curr. Res. Food Sci. 6 (2023) 100465].

[This corrects the article DOI: 10.1016/j.crfs.2023.100465.].

Oleosome interfacial engineering to enhance their functionality in foods.

This study aimed to increase the physical stability of native sunflower oleosomes to expand their range of applications in food. The first objective was to increase the stability and functionality of oleosomes to lower pH since most food products require a pH of 5.5 or lower for microbial stability. Native sunflower oleosomes had a pI of 6.2. One particularly effective strategy for long-term stabilization, both physical and microbial, was the addition of 40% (w/w) glycerol to the oleosomes plus homogenization, which decreased the pI to 5.3 as well as decreasing oleosome size, narrowing the size distribution and increasing colloidal stability. Interfacial engineering of oleosomes by coating them with lecithin and the polysaccharides xanthan and gellan, effectively increased stability, and lowered their pI to 3.0 for lecithin and lower than 3.0 for xanthan. Coating oleosomes also caused a greater absolute value of the ζ-potential; for example, this amount was shifted to -20 mV at pH 4.0 for xanthan and to -28 mV at pH 4.0 for lecithin, which provides electrostatic stabilization. Polysaccharides also provide steric stabilization, which is superior. A significant increase in the diameter of coated oleosomes was observed with lecithin, xanthan and gellan. The oleosome sample with 40% glycerol showed high storage stability at 4 °C (over three months). The addition of glycerol also decreased the water activity of the oleosome suspension to 0.85, which could prevent microbial growth.

Decontamination of water co-polluted by copper, toluene and tetrahydrofuran using lauric acid.

Co-contamination by organic solvents (e.g., toluene and tetrahydrofuran) and metal ions (e.g., Cu2+) is common in industrial wastewater and in industrial sites. This manuscript describes the separation of THF from water in the absence of copper ions, as well as the treatment of water co-polluted with either THF and copper, or toluene and copper. Tetrahydrofuran (THF) and water are freely miscible in the absence of lauric acid. Lauric acid separates the two solvents, as demonstrated by proton nuclear magnetic resonance (1H NMR) and Attenuated Total Reflection-Fourier Transform Infrared Spectroscopy (ATR-FTIR). The purity of the water phase separated from 3:7 (v/v) THF:water mixtures using 1 M lauric acid is ≈87%v/v. Synchrotron small angle X-Ray scattering (SAXS) indicates that lauric acid forms reverse micelles in THF, which swell in the presence of water (to host water in their interior) and ultimately lead to two free phases: 1) THF-rich and 2) water-rich. Deprotonated lauric acid (laurate ions) also induces the migration of Cu2+ ions in either THF (following separation from water) or in toluene (immiscible in water), enabling their removal from water. Laurate ions and copper ions likely interact through physical interactions (e.g., electrostatic interactions) rather than chemical bonds, as shown by ATR-FTIR. Inductively coupled plasma-optical emission spectrometry (ICP-OES) demonstrates up to 60% removal of Cu2+ ions from water co-polluted by CuSO4 or CuCl2 and toluene. While lauric acid emulsifies water and toluene in the absence of copper ions, copper salts destabilize emulsions. This is beneficial, to avoid that copper ions are re-entrained in the water phase alongside with toluene, following their migration in the toluene phase. The effect of copper ions on emulsion stability is explained based on the decreased interfacial activity and compressional rigidity of interfacial films, probed using a Langmuir trough. In wastewater treatment, lauric acid (a powder) can be mixed directly in the polluted water. In the context of groundwater remediation, lauric acid can be solubilized in canola oil to enable its injection to treat aquifers co-polluted by organic solvents and Cu2+. In this application, injectable filters obtained by injecting cationic hydroxyethylcellulose (HEC +) would impede the flow of toluene and copper ions partitioned in it, protecting downstream receptors. Co-contaminants can be subsequently extracted upstream of the filters (using pumping wells), to enable their simultaneous removal from aquifers.

Hardness, plasticity, and oil binding capacity of binary mixtures of natural waxes in oliveoil.

In this study, olive oil oleogels structured with less than 4% binary blends of sunflower wax (SFW), rice bran wax (RBW), candelilla wax (CDW), and beeswax (BW) were characterized. Among the different binary wax oleogels, samples structured with 3% (w/w) of binary mixtures of SFW and RBW, as well as binary mixtures of CDW and BW, displayed a high oil binding capacity relative to any other mixtures. Moreover, in some binary wax oleogels, back extrusion hardness and elastic constant were significantly higher than that of oleogels prepared using the individual waxes. This was interpreted as a synergism between these waxes. Image analysis of oleogel brightfield micrographs indicated that the samples with a higher elastic constant had a lower box-counting fractal dimension and larger crystals, suggesting that this increase in the elastic constant was a consequence of the lower fractal dimension of the wax crystal network, in agreement with established fractal structural-mechanical models for van der Waals colloidal networks. The crystal structure of the individual waxes and their blends showed orthorhombic perpendicular subcell packing arrangements, which did not change upon mixing, suggesting this length scale did not play a role in the observed synergism. The melting point of binary mixtures of waxes in olive oil was in the range of 43.2 °C to 67.4 °C and pseudo-ideal mixing behavior was observed. The hardness and plasticity (brittleness) of the 2% and 3% binary wax mixtures in olive oil characterized using back extrusion, were similar to those of a commercial soft margarine, suggesting a potential use of the wax oleogels as margarine or spread replacers.

Higher palmitic acid and dipalmitoyloleate levels are correlated to increased firmness in commercial butter.

The physical properties of butter are impacted by the fatty acid and triacylglycerol composition of the milkfat. Increased butter hardness and melting temperature results in decreased consumer satisfaction since these affect the culinary performance and spreadability. During the winter of 2021, consumers reported anecdotal evidence of an increase in butter hardness, leading to news reports blaming the increased hardness on palm oil-based supplementation of cows' feed. Commercial butter samples were collected from across Canada to test the correlation between fatty acid and triacylglycerol composition, and hardness. We determined that palmitic acid (r = 0.74) and dipalmitoyloleate (r = 0.72) were significantly and positively correlated to commercial butter hardness (P < 0.01). However, due to restricted access to existing historical data on the chemical composition of milk fat and hardness of butter, it was not possible to compare the firmness of butter in 2021 with butter produced in the past.

Encapsulation of cycloastragenol in phospholipid vesicles enhances transport and delivery across the skin barrier.

Cycloastragenol (CA) is a plant saponin that functions as a telomerase activator, and it has been made as an oral anti-aging supplement and use as active ingredient in topical cosmetic products. The anti-aging performance in cosmetic products have only been evaluated by description of skin appearance, while direct topical penetration of CA across the skin barrier still needs to be confirmed. The objective of this work was to design encapsulation vehicles to deliver CA across the skin barrier using commercially available ingredients through scalable processes, and to prove its topical penetration. Phospholipid vesicles including liposomes, ethosomes, and transethosomes were prepared using soy and sunflower phospholipids and different penetration enhancers, including ethanol and surfactants. The loading capacity of CA was analyzed using high performance liquid chromatography, and the topical penetration of CA was evaluated using Franz diffusion cells with pig skin. Transethosomes using Tween 80, Span 40, or dicetylphosphate as the penetration enhancer showed better CA delivery across the skin barrier than ethosomes or emulsifier α-gels. Results of this work provide evidence that CA encapsulated in phospholipid vesicles can be transported across the skin barrier. These encapsulation systems could be used for the design of CA-containing anti-aging cosmetic products.

Particle filled protein-starch composites as the basis for plant-based meat analogues.

Rapid swelling, high amylopectin starches including Thermally Inhibited (TI), Chemically Modified (CM), and Granular Cold- Swelling (GCS) were assessed for their supporting matrix forming potential and properties. Starches displayed identical calorimetric profiles with no endothermic events, and completely amorphous structure as judged by powder X-ray diffraction. However, they each provided different textural attributes. The starches were combined with pea protein isolate at a total concentration of 47%w/w (d.b.) to create a proteinacious supporting matrix. The starch protein matrix was then tested in a non-cold-set dough state as well as in a cold-set state after storage for 24h at 5oC. In the non-cold-set state, hardness increased with the addition of protein. CM was the softest dough and was difficult to work with, while TI and GCS were harder, with TI having the greatest resilience. Once cold-set, the textural properties changed, and GCS was not able to form a solid structure, instead remaining a viscoelastic dough. The hardness and storage modulus (G') of TI and CM displayed a negative correlation with the addition of protein due to matrix disruption. However, the combination of TI starch and pea protein at a ratio of 70% starch and 30% protein in the dry fraction displayed a synergistic effect, with increased resilience, chewiness, and ductility. FTIR of TI starch and protein at the same 70:30 ratio provided further evidence for the existence of an interaction between pea protein and TI starch. The results support the use of TI rapid swelling starch and pea protein isolate as a supporting matrix for application in meat analogue systems.

Dataset on the small- and large deformation mechanical properties of emulsion-filled gelatin hydrogels as a model particle-filled composite food gel.

In this article we present data related to the original research articles 'Effect of matrix architecture on the elastic behavior of an emulsion-filled polymer gel' (Gravelle et al., 2021) and 'The influence of network architecture on the large deformation and fracture behavior of emulsion-filled gelatin gels' (Gravelle and Marangoni, 2021). The small deformation elastic (Young's) modulus and large deformation fracture behavior of emulsion-filled composite gelatin gels are reported as a function of filler volume fraction (ϕf = 0 - 0.32). Homogeneous and heterogeneous network architectures were achieved by varying electrostatic interactions between matrix and filler. The effect of emulsion droplet physical state (solid fat or liquid oil) and gelator concentration (2, 4, 6, or 8% gelatin) were also evaluated. The reported elastic modulus, and fracture properties were obtained from large deformation uniaxial compression tests. Power law scaling behavior was identified for the elastic modulus as a function of both ϕf and gelator concentration, which are also reported. This data is relevant to the evaluation of network properties on the applicability of small deformation particle reinforcement theories and models describing the fracture mechanics of filled composites such as fat-filled food systems.

Zein-Bonded Graphene and Biosurfactants Enable the Electrokinetic Clean-Up of Hydrocarbons.

Nonaqueous phase liquids (NAPL, e.g., hydrocarbons and chlorinated compounds) are common groundwater pollutants. Electrokinetic remediation of NAPLs uses electric fields to draw them toward electrodes and remove them from groundwater. The treatment requires NAPL mobility. Emulsification increases mobility, but at a risk for downstream receptors. We propose using alkaline aqueous solutions of zein and graphene nanoparticles (GNP) to form conductive materials, which could also act as barriers to control NAPL migration. Alkaline zein-GNP solutions can be injected in the polluted soil and solidified by neutralizing the pH (e.g., with glacial acetic acid, GAA). Shear rheology experiments showed that zein-GNP composites were cohesive, and voltammetry showed that GNP increased electrical conductivity of zein-based materials by 3.5 times. Gas chromatography-mass spectroscopy (GC-MS) demonstrated that the electrokinetic treatment of model sandy aquifers yielded >60% and ∼47% removal of emulsified toluene in freshwater and in salt solutions, respectively (with 30 min treatment using a 10 V differential voltage between a zein-GNP and an aluminum electrode. NaCl was used as model salt contaminant. The conductivity of surfactant solutions was lower in saline water than in freshwater, explaining differences in toluene removal. Toluene-water emulsions were stabilized using the natural surfactants lecithin and saponin. These surfactants acted synergistically in stabilizing emulsions in either freshwater or salt solutions. Lecithin and saponin likely interacted at toluene-water interfaces, as indicated by the morphology, interfacial tension and compressional rigidity of toluene-water interfaces with both components (relative to interfaces of either lecithin or saponin alone). The compressional behavior of interfacial films was well-described by the Marczak model. Electrokinetic treatment of saturated model sandy aquifers also decreased the turbidity of emulsions of water and either tricholoroethylene (TCE, by ∼41%) or diesel (by ∼75%), in the presence of a bacterial biosurfactant. This decrease was used as semiquantitative indicator of NAPL removal from water.

Tempering of cocoa butter and chocolate using minor lipidic components.

Chocolate manufacture includes a complex tempering procedure to direct the crystallization of cocoa butter towards the formation of fat crystal networks with specific polymorphism, nano- and microstructure, melting behavior, surface gloss and mechanical properties. Here we investigate the effects of adding various minor non-triglyceride lipidic components to refined cocoa butter and chocolate on their physical properties. We discover that addition of saturated phosphatidylcholine and phosphatidylethanolamine to neutralized and bleached cocoa butter or molten and recrystallized commercial chocolate at 0.1% (w/w) levels, followed by rapid cooling to 20 °C in the absence of shear, accelerates crystallization, stabilizes the desirable Form V polymorph and induces the formation of chocolate with an optimal microstructure, surface gloss and mechanical strength. Final chocolate structure and properties are comparable to those of a commercial tempered chocolate. Minor lipidic component addition represents an effective way to engineer chocolate material properties at different length scales, thus simplifying the entire tempering process.

Effects of partially replacing animal fat by ethylcellulose based organogels in ground cooked salami.

Partial fat replacement in cooked salamis was formulated using organogels made with canola oil, ethylcellulose (EC; 6, 8, 9, 10, 11, 12 and 14%) and three types of surfactants; i.e., glycerol monostearate (GMS), stearyl alcohol/stearic acid (SOSA) and soybean lecithin (Lec). Texture profile analysis (TPA) and back extrusion tests indicated that increasing EC polymer concentration leads to harder gels regardless of the surfactant used. However, using GMS resulted in the hardest gel, whereas Lec did not strengthen the gel (mechanical stress test), but plasticized it. In general, gel hardness had a distinct effect on the binding of the organogel particle to the meat matrix, with softer gels adhering better under progressive compression. Substituting animal fat with organogel did not affect the main TPA parameters in most salami formulations, and canola oil by itself was also not significantly different from the pork and beef fat control. Using canola oil resulted in very small oil globules compared to the animal fat control, while structuring the oil yielded a microstructure with larger fat particles/globules, similar to the control. Color evaluation revealed a shift to yellow of the treatments with organogels compared to the control, but lightness and redness were not altered. The results demonstrate the potential use of structured vegetable oil to manufacture coarse ground meat products with lower saturated fat and a more favorable nutritional profile while resembling the traditional ground products.

A new fractal structural-mechanical theory of particle-filled colloidal networks with heterogeneous stress translation.

This work addresses the role of rigid inclusions in determining the elastic modulus of particle-filled colloidal networks by modifying an established fractal scaling model. The approach acknowledges the heterogeneous nature of stress distribution at length scales beyond the colloidal aggregates, while maintaining structural information at the level of individual clusters. This was achieved by introducing a scaling factor to account for system heterogeneity which contains intrinsic information about the network's capacity to form load-bearing links. Rigid fillers bound to the network induce stress concentration, but additionally serve as junction zones which introduce additional load-bearing pathways. This gives rise to the observed increase in the modulus with filler volume fraction. The proposed relationship between the load-bearing network connectivity and scaling behavior may have additional implications on the fractal dimension determined by rheological methods. Further, this model accommodates an experimentally observed correlation between the scaling behavior of the modulus associated with the addition of fillers and that arising from increasing structurant concentration. The modified fractal model thus provides an alternative view of how fillers contribute to the small- and large-deformation mechanical behavior of filled colloidal gels in a manner consistent with experimental observations.

Lipase-catalyzed glycerolysis extended to the conversion of a variety of edible oils into structural fats.

Lipase-catalyzed glycerolysis was recently shown to be a viable technique to structure cottonseed and peanut oils into structural fats by converting native triacylglycerols into partial glycerides without changing overall fatty acid composition. Here, this approach was extended to a variety oils of differing fatty acid compositions. Reactions were performed at 65 â€‹°C for 48 â€‹h at a triacylglycerol:glycerol molar ratio of 1:1, using the non-regiospecific Candida antarctica lipase B. In all oil systems, a 20 â€‹°C increase in crystallization onset temperature was observed following glycerolysis. Solid fat content increases resulting from glycerolysis were greatest for oils containing >10% saturated fat along with a high oleic acid content. The solid fat content of tigernut oil at 5 â€‹°C increased from 8% to 34% following glycerolysis. Tigernut glycerolysis product was used to make margarine with plasticity similar to commercial margarine and butter. This research demonstrates that glycerolysis is a general strategy to convert liquid oils into structural fats used in food applications, and thus replace palm oil and hydrogenated fats.

Molecular Origins of Polymorphism in Cocoa Butter.

Cocoa butter displays complex crystallization behavior and six crystal polymorphic forms. Although the crystal structure of cocoa butter has been studied extensively, the molecular interactions between cocoa butter triacylglycerols in relation to polymorphic transformations from metastable forms (forms III and IV) to stable crystal forms (forms V and VI) remain largely unknown. In this review, the triclinic polymorphism and melting profiles of the major triacylglycerols in cocoa butter-POP, POS, and SOS-are reviewed, and their binary and ternary phase behaviors in metastable (pseudoß') and stable (ß2) crystal forms are discussed. We also attempt to clarify how the transformation of cocoa butter from form IV to V, as a critical step in the tempering of chocolate, is controlled by POS interactions with both POP and SOS. Moreover, we show how the crystal forms V and VI of cocoa butter are templated by crystal forms ß3 and ß1 of POS, respectively.

Trypan blue removal from water with zein sorbents and laccase.

ABSTRACT: Zein-based materials were used to remove Trypan blue from water under flow conditions and in batch tests. In flow tests, zein dissolved at pH = 13 was injected in sand columns and subsequently coagulated with CaCl2, to create an adsorbent filter which removed over 99% of Trypan blue. Batch tests were conducted using zein powder, zein dissolved at pH = 13 and coagulated with CaCl2, Fe2Cl3 or citric acid, and zein dissolved in ethanol and then coagulated with water. The highest Trypan blue removal was achieved with zein powder (4000 mg Trypan blue/kg sorbent, as determined through spectrophotometry), followed by zein coagulated with Fe2Cl3 (500 mg Trypan blue/kg sorbent) and with other salts (140 mg Trypan blue/kg sorbent). Differences in the sorption efficiency are attributed to differences in the surface area. The sorption isotherm of Trypan blue onto zein-based sorbents was a Type II isotherm, suggesting physisorption. Desorption of Trypan blue was limited when zein-based coagulated sorbents were immersed in pure water. Trypan blue could be degraded by free laccase in water, as determined through spectrophotometry and electrospray ionization mass spectroscopy (ESI-MS). Trypan blue could also be degraded by laccase when zein-based laccase-containing sorbents were prepared at pH = 10, using Fe2Cl3 as coagulant. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1007/s42452-020-04107-w.

Physical properties of zein networks treated with microbial transglutaminase.

Potential improvements to the physical properties of brittle, self-assembled zein networks through microbial transglutaminase crosslinking were investigated. The formation of crosslinked heteropolymers was also explored with networks containing zein and either soy or pea protein isolates as supplemented lysine sources. The observed SDS-PAGE bands did not show any evidence of zein crosslinking. Soy and pea isolates underwent extensive crosslinking on their own, but heteropolymers were not observed in multiprotein networks with zein. Despite the lack of crosslinking observed, rheological and textural analysis revealed that the enzymatic treatment of zein produced a weaker, more brittle structure. With no significant changes in secondary structure, determined through FTIR, the observed behaviour was primarily attributed to glutamine deamidation by microbial transglutaminase in the absence of sufficient lysine through changes to the hydrophobicity of the protein such that non-covalent bonding within network was modified.