Physical Properties of Soybean Oleogels and Oil Migration Evaluation in Model Praline System

The present study examined the physical properties of soybean oleogels and commercial confectionery filling fats and evaluated the oil migration properties in model praline systems. Soybean oleogels were prepared using different oleogelators namely monoglyceride (MAG oleogels) and a mixture of sorbitan tri‐stearate (STS) with lecithin (50:50) (Lec‐STS oleogels). Both MAG oleogels and Lec‐STS oleogels demonstrated a flat solid fat content (SFC) profile with zero SFC at 40 °C. At low temperature, MAG oleogels and Lec‐STS oleogels demonstrated a non‐flowing gel‐like property due to the ability of the oleogelator to entrap liquid oil. In addition, oleogels also showed thixotropic behavior indicating the possible capability to prevent migration of filling fats to coatings and also good flow ability during pumping though manufacturing equipment. The textural property of oleogels also did not change significantly upon storage indicating good structural stability. When used as in a model praline system, oleogels demonstrated a migration delaying property.     

Oxidative stability and characterization of oleogels obtained from safflower oil-based beeswax and rice bran wax and their effect on the quality of cake samples

Safflower oil-based oleogels were produced from beeswax and rice bran wax. Oleogels demonstrated higher oxidative stability than shortening at the cooking temperature. Peroxide values in shortening, rice bran wax oleogels, and beeswax oleogels samples were found in the range of 4.8–27.76, 13.21–20.45 and 4.30–7.72 meqO₂kg⁻¹ oil. Following oleogelation, there was no significant change in fatty acid composition of safflower oil. In addition, after baking process, the changes in the major fatty acids were not determined to be significant. Solid fat content ratios (carried out at 35°C) of rice bran wax oleogels, in beeswax oleogels and in shortening samples were defined in the range of 4.10%–7.70%, 0.80%–5.00%, and 9.61%, respectively. The highest oil binding capacity was revealed in beeswax oleogels with 99.93%–99.98%. The shortest crystallization time was determined as 3 min in oleogel containing 10% rice bran wax. Cakes consisted of oleogel were acceptable in terms of texture and sensory properties compared to cake produced with shortening. Sensory results revealed that some cakes produced with oleogels were found to be more acceptable as compared with control group samples. In this respect, oleogels produced with safflower oil-based beeswax and rice bran wax could be used instead of commercial solid fat widely used in the cake industry.     

Influence of pH and protei thermal treatment on the rheology of pea protein-stabilized oil-in-water emulsions

The influence of emulsion pH and previous thermal treatment of the protein on the rheological behavior of pea protein-stabilized emulsions has been studied. Oil-in-water emulsions with 65% weight oil and 6% weight pea protein isolate were prepared. Emulsion pH was varied between 3.5 and 7.0. In addition to this, the protein aqueous phase was submitted to different previous thermal treatments by modifying temperature from 25 to 90°C and heating time from 20 to 60 min. To study the influence of the above-mentioned variables, droplet size distribution and steady-state flow curves were determined, and linear viscoelastic measurements were carried out. An increase in the pH of the emulsion initially leads to an increase in emulsion viscosity and viscoelastic functions, as well as to a decrease in the mean droplet size, up to an emulsion pH close to the protein isoelectric point, where a singular rheological behavior is found. An increase in temperature or heating time on the protein aqueous phase yields higher values of steady-state viscosity and linear viscoelasticity functions, up to a complete denaturation of the protein.     

Effect of oil unsaturation and wax composition on stability,properties and food applicability of oleogels

Oleogelation is emerging as one of the most exigent oil structuring technique. The main objective of this study was to formulate and characterize rice bran/sunflower wax-based oleogels using eight refined food grade oils such as sunflower oil, mustard oil, soybean oil, sesame oil, groundnut oil, rice bran oil, palm oil, and coconut oil. Stability and properties of these oleogels with respect to oil unsaturation and wax composition were explored. Sunflower wax exhibited excellent gelation ability even at 1%–1.5% (w/v) concentration compared to rice bran wax (8%–10% w/v). As the oleogelator concentration increased, peak melting temperature also increased with increase in strength of oleogels as per rheological studies. X-ray diffraction and morphological studies revealed that oleogel microstructure has major influence of wax composition only. Sunflower wax oleogels unveiled rapid crystal formation with maximum oil binding capacity of 99.46% in highly unsaturated sunflower oil with maximum polyunsaturated fatty acid content. Further, the applicability of this wax based oleogels as solid fat substitute in marketed butter products was also scrutinized. The lowest value of solid fat content (SFC) in oleogel was 0.20% at 25°C, resembling closely with the marketed butter products. With increase in oil unsaturation, oleogels displayed remarkable reduction in SFC. Depending upon prerequisite, oleogel properties can be modulated by tuning wax type and oil unsaturation. In conclusion, this wax-based oleogel can be used as solid fat substitute in food products with extensive applications in other fields too.     

Physical Properties of Candelilla Wax,Monoacylglycerols, and Fully Hydrogenated Oil Oleogels

Oleogels have been studied in the past decade due to their potential to replace saturated fat in foods. Oleogelators have been mostly studied alone or in binary systems. Sometimes a single oleogelator cannot achieve all the technological properties necessary for a specific food application. Thus, the aim of this work was to investigate the interaction between candelilla wax (CLX), monoacylglycerols (MAG), and a fully hydrogenated oil (hardfat [HF]) in soybean and high‐oleic sunflower oils and to evaluate their physical properties. The concentration of the total oleogelator was between 5% and 10%, from pure CLX (5%), sample OP, up to many combinations of MAG, HF, and CLX samples O1, O2, O3, O4, O5, and O6. Samples were evaluated according to their microstructure, melting properties, rheological behavior, hardness, oil‐binding capacity (OBC), and thermal stability. Results showed that the addition of MAG and HF to CLX created a softer gel but improved its rheological properties. Changes in the physical properties were related to the various proportions of CLX, MAG, and HF rather than the overall concentration of structuring agents. For example, for a total concentration of 5% of the structuring agent, a decrease in the CLX concentration from 5% to 3% and the addition of HF and MAG resulted in a softer crystalline network. Increasing the overall concentration of oleogelators by increasing the amount of HF and/or MAG and maintaining the concentration of the CLX constant did not improve the hardness of the gel. This study showed that at least 3% of CLX must be added to the system to obtain a semisolid material independently of the amount of MAG and/or HF added.     

Optimization of the composition of low-fat oil-in-water emulsions stabilized by white lupin protein

The effect of composition (protein, xanthan gum, and oil content) of lupin protein-stabilized emulsions on their physical properties—droplet size distribution, rheological behavior, and texture—was studied. Droplet size distribution was measured by laser light-scattering experiments, rheological parameters were determined from oscillatory and steady-state flow measurements, and texture responses were obtained from texture profile analysis. Response surface methodology was used to optimize the emulsion composition using commercial mayonnaise parameters as a standard. An increase in protein, xanthan gum, or oil content produced, in the experimental range considered, an increase in the rheological and textural parameters studied, as well as a decrease in the average oil droplet diameter. It was possible to produce stable lupin protein-stabilized emulsions with physical properties similar to those of commercial mayonnaise for a wide variety of protein, xanthan gum, and oil concentration values, which may be designed to suit market specifications.     

Utilization of Beeswax Oleogel-Shortening Mixtures in Gluten-Free Bakery Products

Formulating gluten-free bakery products with acceptable physical properties generally requires a high amount of fat. As the fat used in these products is often high in saturated fatty acids, the objective of this study was to evaluate beeswax (BW) containing oleogels for partial replacement of the shortening in gluten-free aerated products. Oleogels prepared with BW were cocrystallized with a commercial cake shortening in the laboratory scale crystallization unit. Then, the resulting blends were evaluated in the gluten-free cake formulations. When the BW oleogel was used alone, the overrun values of the batter samples decreased, indicating reduced air-holding ability. Product porosity and specific volume of the samples were also diminished with complete replacement of the shortening with BW oleogel. Nevertheless, 45%, 30%, and 15% replacement of the shortening with BW oleogel resulted in batter and baked product properties comparable to those of the control products. Rheological and textural measurements, microscopy, and bubble size distribution suggested that gradual replacement of shortening with oleogels may be an alternative method for a partial reduction of saturated fat without altering the physical properties of gluten-free aerated products.     

Propolis and carnauba wax-based safflower oil oleogels as fat substitutes in cakes: Production,oxidative stability,and characterization

In this study, safflower oil oleogels were made using propolis wax and carnauba wax in three different concentrations each, and their effectiveness as a fat substitute in cake was evaluated afterward. Oleogels' oxidative stability and characterization were looked into. In oleogels, the oil binding capacity, solid fat content, and crystallization time were all assessed. The cakes underwent an examination for moisture content, texture, and sensory evaluation. Additionally, analyses of fatty acid composition, free fatty acidity, oxidative stability (peroxide value, conjugated diene-triene), 3-monochloropropane-1,2-diol (3-MCPD), and glycidyl were carried out both before and after baking in oleogels and shortening. Several of the physical, textural, and sensory qualities of the oleogel-based cakes were acceptable when compared to those of the shortening-based cakes. The general acceptability of cakes made with carnauba wax was very high and almost under control. The acceptability of cakes made with propolis wax oleogels was lower than this. The study of these criteria has shown that safflower oil-based carnauba and propolis wax oleogels can be utilized to produce high-quality, healthful cakes with a high amount of unsaturated fatty acids. Practical Applications : To replace fat phases in cake products high in saturated fatty acids and to enhance the fatty acid profile of the cakes, safflower oil-based oleogels with propolis wax and carnauba wax are a very good option. The results obtained provide useful information for the production of high-quality cakes with higher unsaturated fatty acid content, recommended for a healthier diet, with these oleogels containing different concentrations of oleogelator.     

Oleogel Fabrication Based on Sodium Caseinate,Hydroxypropyl Methylcellulose,and Beeswax: Effect of Concentration,Oleogelation Method,and Their Optimization

In the present study, the oleogel preparation with hydroxypropyl methylcellulose (HPMC) (0–2 g/100 g), sodium caseinate (CN) (0–4 g/100 g), beeswax (0–5 g/100 g), and oleogelation method (foam and emulsion template) was optimized using response surface methodology (RSM) to attain the desirable oil retaining ability, rheological, and textural characteristics. For all the chosen responses, the quadratic model was the best-fitting model with a determination coefficient of R² > 0.91. Results exhibited that the HPMC and CN concentrations were the most influential tested factors on the oil binding capacity, textural, and rheological characteristics of the oleogels due to the formation of more complex and strong network. There was a significant improvement in oil binding capacity and structure recovery of samples by beeswax addition. To produce oleogel similar to industrial shortening, the optimization method was done based on maximum oil binding capacity and thixotropic recovery and other responses were chosen equal to those of shortening values (ɳ_a = 330 Pa.s, G′ = 276,543 Pa, A value = 164,308 Pa s rad⁻¹, and firmness = 44.99 g). As regards the optimized level of structuring agents and responses (ɳ_a = 317 and 329 Pa.s, G′ = 249,782 and 260,997 Pa, A value = 180,022 and 180,373 Pa s rad⁻¹, and firmness = 44.37 and 36.98 g corresponding to Optimization 1 and Optimization 2, respectively), fabrication of oleogels with at least 90 g/100 g trans-free and low saturated oil and attributes close to industrial shortening is possible.     

Functional Food Ingredients Based on Sunflower Protein Concentrates Naturally Enriched with Antioxidant Phenolic Compounds

The functional properties of three sunflower protein concentrates having different content of phenolic compounds (mainly chlorogenic and caffeic acids) obtained from sunflower oil cake, a by-product of the oil industry, were evaluated. Sunflower protein concentrates exhibited high water solubility and moderate water-imbibing and water-holding capacities. It was possible to obtain foams and emulsions of different stability at different pH and ionic strength from these protein concentrates, as well as self-supporting gels produced by thermal induction. The presence of phenolic compounds not only conferred antioxidant activity and changed the color of protein products, but also reduced the water imbibing capacity of sunflower protein concentrates, the stability of the emulsions obtained, and the hardness of protein gels. In contrast, phenolic compounds did not modify the water holding capacity, their water solubility or their foaming properties. These results suggest that these protein products may be used as functional ingredients in the food industry.     

Structure and Physical Properties of Plant Wax Crystal Networks and Their Relationship to Oil Binding Capacity

The microstructure, melting and crystallization behavior, rheological properties and oil binding capacity of crystalline networks of plant-derived waxes in edible oil were studied and then compared amongst different wax types. The critical concentrations for oleogelation of canola oil by rice bran wax (RBX), sunflower wax, candelilla wax, and carnauba wax were 1, 1, 2, and 4 %, respectively, suggesting RBX and sunflower wax are more efficient structurants. A phenomenological two-phase exponential decay model was implemented to quantify the oil-binding capacity of these oleogels. Parameters obtained from this empirical model were then evaluated against microscale structural attributes such as crystal size, mass distribution and porosity to determine the structural dependence of oil-binding capacity. Gels containing candelilla wax exhibited the greatest oil-binding capacity, as they retained nearly 90 % of their oil. This is due to the small crystal size as well as the spatial distribution of these crystals. Using a microscopic to macroscopic approach, this study examines how the structural characteristics unique to each wax and resulting oleogel system affect functionality and macroscopic behavior.     

Determining the structure and stability of essential oil-sunflower wax and beeswax oleogels

In this study, essential oil oleogels were produced using eucalyptus, lavender, lemon peel and tea tree oils with sunflower and beeswax. The physicochemical, thermal, textural, and structural features of the oleogels were determined. For the essential oils used, an addition level of less than 15% of beeswax (BW) was insufficient to form stable oleogels, whereas an addition level of 10% of sunflower wax (SW) was sufficient to form stable oleogels. The acid and peroxide values of the gels were higher than those of the oils. All of the oleogels exhibited peaks around 3.70 and 4.10, indicating the presence of β' polymorphic forms. The hardness and stickiness values of the oleogels were influenced by the type and level of wax addition, as well as the viscosity of the oil used. Based on the thermal analysis results, the oleogels based on beeswax exhibited lower melting properties compared to those based on sunflower wax. The thermogravimetric data indicated that the polymeric matrices formed by the waxes, which depended on the type and level of wax addition, affected the vaporization of the volatiles. In conclusion, oleogels represent a green and sustainable approach for reducing the loss of volatile or bioactive compounds from various essential oils, which are widely used in the food, cosmetics, and pharmaceutical industries.     

Characterization and comparison of oleogels and emulgels prepared from Schizochytrium algal oil using monolaurin and MAG/DAG as gelators

Oleogels and emulgels were developed with winterized algal oil from Schizochytrium spp. rich in ω-3 fatty acids (FAs) to overcome physical limitations of using a highly unsaturated lipid source in food applications. Both gel types were developed using monolaurin or a combination of mono- and diacylglycerols (MAG/DAG) as the gelator at concentrations of 8%, 10%, or 12% (w/w) in oil or emulsion. A 30-day oxidation study was conducted using peroxide value, p-Anisidine value, and change in FA composition to measure the level of oxidation. Oleogel and emulgel samples exhibited a higher oxidative stability than bulk algal oil and oil-in-water emulsion as control groups, respectively. The 12% monolaurin oleogel outperformed others in oxidative stability, preventing oxidation of approximately 11.66% and 7.86% of EPA and DHA, respectively, compared to algal oil. Physical characteristics including thermal behavior, solid fat content (SFC), rheology, morphology, and polymorphism were studied. Results indicated that MAG/DAG oleogels and monolaurin emulgels were the most physically stable. The SFC of 12% MAG/DAG oleogel at 30°C was 10.27% whereas 12% monolaurin oleogel was only 4.51%. Both gel types developed with monolaurin and MAG/DAG could be used for different applications as they exhibited desirable qualities such as oxidative stability and improved physical characteristics.     

Study on the Introduction of Solid Fat with a High Content of Unsaturated Fatty Acids to Gluten-Free Muffins as a Basis for Designing Food with Higher Health Value

Background: Shortenings are high in undesirable nutritionally saturated fatty acids. The aim of the study was to produce gluten-free muffins (GFM) of increased health quality and available to people intolerant to gluten, in which the shortenings were replaced with solid oleogels, consisting of 95% rapeseed oil. Methods: The dough and baked products were subjected to physical, textural, and structural analyses. Moreover, the fatty acids composition, chemical quality of fats extracted from muffins, and color of the products were determined. The dough was also observed at 600× magnification in bright field and polarized light microscopy, and microtomographic analysis of the structure of GTM was performed. Results: There was no effect of the type of lipids on physical properties, including water content in gluten-free muffins. However, the baked products differed in total porosity and brightness, as well as intensity of red and yellow colors. The use of rapeseed oil oleogels, instead of shortening in the muffin recipe, resulted in a decrease in the dietary undesirable SFA in lipid fractions (by approximately 40%), an increase in the content of MUFA (by approximately 30%), and an increase in the content of PUFA (by approximately 15%), with acceptable chemical quality. Conclusions: Research confirms the possibility of obtaining products with increased nutritional value available to consumers on a gluten-free diet.     

Physical Properties of Beeswax,Sunflower Wax,and Candelilla Wax Mixtures and Oleogels

To be able to tailor and optimize the physical properties of oleogels for various food applications, more information is needed to understand how different gelators interact. Therefore, the objectives of this study were to evaluate the interactions between binary mixtures of beeswax (BW), candelilla wax (CLW), and sunflower wax (SFW) in pure form as well as in 5% wax oleogels made with soybean oil, in terms of their crystallization and melting properties, crystal morphology, solid fat content, and gel firmness. CLW:BW mixtures had eutectic melting properties, and oleogels from these mixtures with 40:60 to 90:10 CLW:BW were firmer compared to oleogels made with one wax. The main components in SFW and BW appeared to cocrystallize or crystallize at the same temperature, but nonlinear changes in melting point and solid fat content profile of oleogels prepared with the mixed waxes indicated that SFW dominated oleogel formation. In addition, oleogels prepared with mixtures of SFW and BW had lower firmness compared to oleogels prepared with one wax, indicating an incompatibility between the two waxes. The main wax components in SFW and CLW never cocrystallized, and low levels of CLW appeared to prevent SFW from forming a crystalline platelet network. This resulted in low firmness of oleogels made from mixtures of 90:10 to 60:40 SFW:CLW compared to oleogels prepared with one wax. However, the firmest oleogels of all mixtures were made from 10:90 SFW:CLW. Changes in gel firmness and melting properties with mixed wax oleogels were likely to be due to changes observed in the crystal size and morphology. In addition, the firmest gels were shown to result from mixtures that were predicted to have >40% hydrocarbon content, and a high hydrocarbon to wax ester ratio, but minor components such as free fatty acids and fatty alcohols may have also influenced firmness.     

Proteins of the castor bean—Their preparation,properties, and utilization

Summary This article is a review of technical papers and information that are now available on the proteins of the castor bean. Included among the various aspects of the subject are the following: The chemical composition of castor bean seeds and castor cake; the preparation and properties of their proteins, including the toxic albumin riein, its properties, physiological reactions and amino acid content; the allergenic properties of castor bean protein; the utilization of castor bean cake or pomace for feeding, fertilizer and industrial purposes. An extensive bibliography is appended. A part of this paper was prepared while the author was previously connected with the Bureau of Agricultural and Industrial Chemistry of this Department.     

Effect of Evening Primrose (Oenothera biennis) Oil Cake on the Properties of Polyurethane/Polyisocyanurate Bio-Composites

Rigid polyurethane/polyisocyanurate (RPU/PIR) foam formulations were modified by evening primrose (Oenothera biennis) oil cake as a bio-filler in the amount of 5 to 50 wt.%. The obtained foams were tested in terms of processing parameters, cellular structure (SEM analysis), physico-mechanical properties (apparent density, compressive strength, brittleness, accelerated aging tests), thermal insulation properties (thermal conductivity coefficient, closed cells content, absorbability and water absorption), flammability, smoke emission, and thermal properties. The obtained results showed that the amount of bio-filler had a significant influence on the morphology of the modified foams. Thorough mixing of the polyurethane premix allowed better homogenization of the bio-filler in the polyurethane matrix, resulting in a regular cellular structure. This resulted in an improvement in the physico-mechanical and thermal insulation properties as well as a reduction in the flammability of the obtained materials. This research provided important information on the management of the waste product from the edible oil industry and the production process of fire-safe RPU/PIR foams with improved performance properties. Due to these beneficial effects, it was found that the use of evening primrose oil cake as a bio-filler for RPU/PIR foams opens a new way of waste management to obtain new “green” materials.     

Profile and Functional Properties of Seed Proteins from Six Pea (Pisum sativum) Genotypes

Extractability, extractable protein compositions, technological-functional properties of pea (Pisum sativum) proteins from six genotypes grown in Serbia were investigated. Also, the relationship between these characteristics was presented. Investigated genotypes showed significant differences in storage protein content, composition and extractability. The ratio of vicilin:legumin concentrations, as well as the ratio of vicilin + convicilin: Legumin concentrations were positively correlated with extractability. Our data suggest that the higher level of vicilin and/or a lower level of legumin have a positive influence on protein extractability. The emulsion activity index (EAI) was strongly and positively correlated with the solubility, while no significant correlation was found between emulsion stability (ESI) and solubility, nor between foaming properties and solubility. No association was evident between ESI and EAI. A moderate positive correlation between emulsion stability and foam capacity was observed. Proteins from the investigated genotypes expressed significantly different emulsifying properties and foam capacity at different pH values, whereas low foam stability was detected. It appears that genotype has considerable influence on content, composition and technological-functional properties of pea bean proteins. This fact can be very useful for food scientists in efforts to improve the quality of peas and pea protein products.     

Toxic Compound, Anti-Nutritional Factors and Functional Properties of Protein Isolated from Detoxified Jatropha curcas Seed Cake

Jatropha curcas is a multipurpose tree, which has potential as an alternative source for biodiesel. All of its parts can also be used for human food, animal feed, fertilizer, fuel and traditional medicine. J. curcas seed cake is a low-value by-product obtained from biodiesel production. The seed cake, however, has a high amount of protein, with the presence of a main toxic compound: phorbol esters as well as anti-nutritional factors: trypsin inhibitors, phytic acid, lectin and saponin. The objective of this work was to detoxify J. curcas seed cake and study the toxin, anti-nutritional factors and also functional properties of the protein isolated from the detoxified seed cake. The yield of protein isolate was approximately 70.9%. The protein isolate was obtained without a detectable level of phorbol esters. The solubility of the protein isolate was maximal at pH 12.0 and minimal at pH 4.0. The water and oil binding capacities of the protein isolate were 1.76 g water/g protein and 1.07 mL oil/g protein, respectively. The foam capacity and stability, including emulsion activity and stability of protein isolate, had higher values in a range of basic pHs, while foam and emulsion stabilities decreased with increasing time. The results suggest that the detoxified J. curcas seed cake has potential to be exploited as a novel source of functional protein for food applications.     

Comparing responses of grain legumes, wheat and canola to applications of superphosphate

Phosphorus (P) is a major deficiency of soils of south-western Australia (WA). The fertilizer P requirements are not known for grain legumes being evaluated for neutral to alkaline, fine textured soils in WA. To rectify this, glasshouse and field experiments were undertaken to compare the responses of several grain legume species, wheat and canola to applications of single superphosphate and the results are reported in this paper. The glasshouse experiments measured responses of dried tops, harvested at 26 to 42 days after sowing, to P that was freshly-applied (current P) and previously-applied (previous P). Responses in the glasshouse were measured using yield, P concentration and P content (P concentration multiplied by yield) of oven dried tops of the following: wheat (Triticum aestivum), canola (Brassica napus), faba bean (Vicia faba), chickpea (Cicer arietinum), lentil (Lens culinaris), field pea (Pisum sativum), albus lupin (Lupinus albus) and narrow leaf lupin (Lupinus angustifolius). Field experiments in 1994 and 1995 compared seed (grain) yield responses of faba bean, chickpea, lentil, albus lupin and wheat to applications of current P. The P was banded (drilled) with the seed while sowing at 5 cm depth. Canola and wheat produced very large yield responses to increasing applications of current P. Responses were much smaller for albus lupin, faba bean and chickpea. Responses for lentil, narrow leaf lupin and field pea, fell in between responses of the small and large seeded species. Similar trends for responses were obtained as measured using yield, P concentration, or P content. For soils treated with previous P, similar trends were observed as for current P, but differences in yield responses between species were much less marked and the response curves tended to become more sigmoid. In the field experiments, grain yield responses to current P of albus lupin and chickpea were less than that for wheat. Relative to wheat, faba bean was the most responsive grain legume to applications of current P, with lentil producing similar responses to wheat in one experiment at a newly cleared, P deficient site.