Tailoring Properties of Mixed-Component Oleogels: Wax and Monoglyceride Interactions Towards Flaxseed Oil Structuring

Abstract

The combination of oleogelators in oil structuring has an untapped potential, since effective pairs have usually been found by serendipity. The aim of this work was to evaluate the combination of berry (BEW) or sunflower wax (SHW) with glycerol monostearate (GMS) in flaxseed oil (FXO) at 5 and 25 °C. The thermal and mechanical properties, microstructure, and stability of oleogels were investigated. Self-standing and translucent gels were obtained from BEW in FXO. However, the mixture BEW:GMS resulted in a decrease of dynamic moduli. Moreover, changes in the crystal network and a reduction of oil binding capacity were noticed. Thus, the GMS prevented the complete organization of BEW in polyunsaturated chains of FXO. Conversely, a positive interaction was found for GMS:SHW, since both alone were not able to impart the structure in FXO. Interestingly, gel was formed with improved properties, even with a small addition of GMS, although an ideal ratio of 1:1 (GMS50:50SHW) was found. Oxidative stability analysis showed that all gels resembled the behavior of liquid oil (~12.00 meqO2/kg) over 30 days storage. Therefore, semi-solid systems with nutritional and techno-functional claims were created by using waxes and fatty-acid derivative oleogelator in a rational fashion; this opened the opportunity to tailor oleogel properties.

Budesonide Compatibility Study With Excipients for Preparation of Nanoparticle

“…The pH of the solution led the development of lamellar structures in the mixture, regardless of the ratios between GMS and budesonide. It promoted the formation of crystal-like structures leading to the formation of fine particles [20,23,24]. The same phenomenon might have occurred in this mixture leading to the formation of the fine particles at 40 °C±2 °C/75% RH±5% RH and 25 °C±2 °C/60% RH±5% RH one-month conditions.…”

“…As an effective stabilizer, polar and non-polar compounds which can form water-in-oil or oil-in-water emulsions act as a shared solvent. These properties also make it helpful as a dispersing agent for pigments in oils or solids in fats, or as a solvent for phospholipids such as lecithin [20,21]. When using glyceryl monostearate in a formulation, the possibility of polymorph formation should be recognized.…”

Application of Analytical Methods for the Comprehensive Analysis of Oleogels—A Review

“…Cryogenic-temperature transmission electron microscopy (cryo-TEM) allows the analysis of the morphology of the basic building blocks, the dimension of the observed platelets varying with the supersaturation of the oleogel [47]. When the initial stage of physical gelation is the self-assembly or self-aggregation of the gelator molecules and the process is influenced by the surface area of the gelator or surface roughness, a scanning electron microscope can also be used for analysis [16]. The major inconveniences related to electron microscopy are the necessities of removing the liquid phase from the system with organic solvents, which might affect the structure or cause polymorphic transitions.…”

“…Monoglicerydes were reported to change the configuration of the beeswax network to a structure reassembling platelets piled upon each other (Figure 2b). Moreover, when glycerol monostearate (GMS) was mixed with sunflower wax (SFW), different crystal networks were observed: a sponge-like network for the GMS:SFW (25:75) combination and a platelet organization with a different display for GMS:SFW (50:50) [16].…”

“…Oleogel properties are influenced by intrinsic factors such as the type of oil and the oleogelators involved in the process [14,15], the interactions amongst the gelator and the oil molecules, but also by impurities or minor components [15]. The influence of the type of oil is explained as follows: the presence of a greater unsaturation degree and bended chains cause a larger molar volume and a higher conformational freedom, and affect the structuring mechanism, different behaviours being registered for polymeric strands in comparison to the lamellar phases [16]. Solvent properties and solubility parameters influence numerous self-assembly gelators, along with external conditions affecting primary structures and forces which lead to epitaxial growth into axially symmetric elongated aggregates [15,17].…”