Feasibility of Hemp Seed Oil Oleogels Structured with Natural Wax as Solid Fat Replacement in Margarine

Cold-pressed hempseed oil (HSO) is known to have many health benefits due to many phytochemicals and high polyunsaturated fatty acids content. In this study, HSO oleogels were prepared with 3, 5, and 7% natural waxes including sunflower wax (SW), rice bran wax (RBW), beeswax, and candelilla wax to evaluate their potential as solid fat replacements in margarines and spreads. Firmness, crystal structures, and melting properties of these oleogels were evaluated. In general, wax-based HSO oleogels except for RBW-HSO oleogels had lower firmness and weaker crystal network than the corresponding soybean oil (SBO) oleogels. In contrast, RBW-HSO oleogels had similar firmness, comparable or stronger crystal network, and higher melting and crystallization enthalpies compared to those of SBO oleogels. After removing polar compounds from HSO, waxes except for RBW provided oleogels with greater firmness, higher melting and crystallization enthalpies, and stronger crystal network. Therefore, it was concluded that polar compounds negatively affected the physical properties of wax-HSO oleogels but not those of RBW-HSO oleogels. Margarine samples were prepared with SW- and RBW-HSO oleogels, and their firmness and melting properties were examined. The firmness of these margarines indicated that wax-HSO oleogels may achieve the firmness of commercial spreads with less than 3% wax while the firmness of stick margarines cannot be achieved even with 7% wax. Although the properties of wax-HSO oleogels should be further improved, they showed potential as solid fat replacements in margarines and spreads.

Influence of the Mixtures of Vegetable Oil and Vitamin E over the Microstructure and Rheology of Organogels

Candelilla wax (CW) and 12-hydroxystearic acid (12HSA) are classic solid-fiber-matrix organogelators. Despite the high number of studies using those ingredients in oily systems, there is scarce literature using a mixture of oil and antioxidants. Vitamin E (VE) is an important candidate for its lipophilicity and several applications on pharmaceutical, cosmetics, and food industries. In this work, we investigated the influences of mixtures between vegetable oil (VO) and VE on the microstructures and rheological properties of CW and 12HSA organogels. A weak gel (G′′/G′ > 0.1) with a shear-thinning behavior was observed for all samples. The presence of VE impacted the gel strength and the phase transition temperatures in a dose-dependent pattern. Larger and denser packed crystals were seen for 12HSA samples, while smaller and more dispersed structures were obtained for CW organogels. The results obtained in this work allowed the correlation of the structural and mechanical properties of the organogels, which plays an important role in the physical-chemical characteristics of these materials.

Development of Antioxidant-Fortified Oleogel and Its Application as a Solid Fat Replacer to Muffin

Oleogelation has recently received a great deal of attention in the food industry as a novel alternative technology that physically converts liquid oil into semi-solid gel. Since the functional characteristics of oleogels are dependent on the gelators or bioactive compounds incorporated, this study was undertaken to evaluate the rheological properties and oxidative stability of candelilla wax oleogels fortified with glycerol monostearate (GMS) and β-carotene, and also to investigate their applications to muffin as a shortening replacer. The interaction between candelilla wax and GMS contributed to strengthening the oleogel structure. The oleogels with β-carotene showed the lowest peroxide values than the other samples. The muffins prepared with oleogels for shortening had greater specific gravity and harder texture, but there was no significant difference in the specific volume between the shortening and oleogel samples with GMS. In addition, muffins with β-carotene oleogels showed the highest oxidative stability. Therefore, this study indicated that the incorporation of β-carotene and GMS in oleogels positively affected the storage stability of muffin.

Microcrystalline cellulose effects on the rheology of mixed oleogels structured with candelilla wax and saturated fat

The structuration processes of mixed oleogels produced with candelilla wax (CW, 0 or 3%), fully hydrogenated soybean oil (FH, 5-15%), and microcrystalline cellulose (MC, 0-9%) were studied to define their rheological effects. During the cooling CW crystals performed as nucleation sites for FH. The elastic modulus (G’) of oleogels with FH and 3% CW were more than two orders of magnitude higher than those produced with 0% CW. Adding MC to the oleogels increased slightly the G’. Independently of the amount of MC, oleogels structured with increasing amounts of FH and 0% CW showed the elastic properties scaling of colloidal gels. This behavior was lost by adding 3% CW, implying that in mixed FH-CW oleogels, the CW crystal network dominated the oleogel rheology. The flow point and the mechanical reversibility of oleogels and commercial butter (CB) was also determined. CB showed flow points at 44 and 59% strain and mechanical reversibility values of 29 and 35% of G’ measured in a pre-shear step. Adding MC to oleogels structured with FH and 0% CW increased their flow point (37.2%) near those of CB. This effect was not produced in mixed FH-3% CW oleogels. The mechanical recovery of oleogels produced with FH, MC, and 0% CW tend to decrease as the FH content increased. CW and MC did not show a simple concentration–effect relationship for the mechanical recovery. Nonetheless, oleogels structured with 3% CW and 10% FH and 6-9% MC showed mechanical recovery (~60%) close to that of CB.

Variations in Microstructural and Physicochemical Properties of Candelilla Wax/Rice Bran Oil–Derived Oleogels Using Sunflower Lecithin and Soya Lecithin

Candelilla wax (CW) is a well-known oleogelator that displays tremendous oil-structuring potential. Lecithin acts as a crystal modifier due to its potential to alter the shape and size of the fat crystals by interacting with the wax molecules. The proposed work is an attempt to understand the impact of differently sourced lecithin, such as sunflower lecithin (SFL) and soya lecithin (SYL), on the various physicochemical properties of CW and rice bran oil (RBO) oleogels. The yellowish-white appearance of all samples and other effects of lecithin on the appearance of oleogels were initially quantified by using CIELab color parameters. The microstructural visualization confirmed grainy and globular fat structures of varied size, density, packing, and brightness. Samples made by using 5 mg of SFL (Sf5) and 1 mg of SYL (Sy1) in 20 g showed bright micrographs consisting of fat structures with better packing that might have been due to the improvised crystallinity in the said samples. The FTIR spectra of the prepared samples displayed no significant differences in the molecular interactions among the samples. Additionally, the slow crystallization kinetics of Sf5 and Sy1 correlated with better crystal packing and fewer crystal defects. The DSC endotherm displayed two peaks for melting corresponding to the melting of different molecular components of CW. However, all the formulations showed a characteristic crystallization peak at ~40 °C. The structural reorganization and crystal growth due to the addition of lecithin affected its mechanical property significantly. The spreadability test among all prepared oleogels showed better spreadable properties for Sf5 and Sy1 oleogel. The inclusion of lecithin in oleogels has demonstrated an enhancement in oleogel properties that allows them to be included in various food products.

Organogels as nutraceutical carriers: Effect of addition of lecithin, tocopherols, and EPA/DHA on properties of candelilla wax-soybean oil organogels

Organogels are semisolid and 3D systems in which both an organic liquid solvent and other dispersed particles are entrapped. Today there is not much information about the potential of organogels as carriers of lipophilic nutraceuticals. Therefore, in this work, the preparation and characterization of soybean oil-based organogels with candelilla wax (CW) and lecithin, tocopherol, or EPA/DHA were studied. Soybean oil was structured with 0.5, 1.0, 2.0, and 4.0% w/w of CW. In the organogels, the visual appearance, thermal stability, color parameters, microstructure, hardness, and rheological properties were analyzed. Results showed that soybean oil was successfully structured into an array of solid-like organogels varying in concentrations of CW and added nutraceutical compounds. Increasing CW concentration yielded stronger 3D-network gel formation (type 5 or solid organogel). All organogels were stable at 5, 25, and 35°C during the cyclization process. The nutraceuticals affected the color parameters and 3D network structure. Larger crystalline spherulites and a uniform microstructure were observed, especially in organogels formulated with 4.0% w/w of CW and lecithin. In comparison with the control, organogels (4.0% w/w) with tocopherol or EPA/DHA required lower shear stress to flow whereas lecithin required higher shear stress to flow. Texture analysis showed that organogels with nutraceuticals presented higher hardness, this behavior was attributed to the formation of a larger and softer crystal networks. In conclusion, soybean oil-based organogels formulated with lecithin, tocopherol, or EPA/DHA yielded stable organogels with promising properties as nutraceutical carriers.