MGC and SAT of OGs
Table 1 shows the results of fatty acid composition of vegetable oils and monoglycerides obtained by GC. The difference in the composition of saturated (SFA), monounsaturated (MFA) and polyunsaturated (PFA) fatty acids was observed in both oils and MY. CA was found to be rich mostly in medium-chain MFA and PFA (66.28 and 27.78%), while CN is mainly composed of short-chain SFA (90.82%). FA composition for these oils is similar to that reported by other authors (Garcia-Andrade et al., 2020), however, the FA profile of MY was different from that reported by Giacomozzi et al. (2021), (C16:0 43.91±0.07% and C18:0 53.65±0.07%). Even being the gelling agent Myverol, the product used for this investigation had a higher percentage of C16:0 (palmitate, 58.72±0.10%) and lower percentage of C18:0 (stearate 39.67±0.11%). However, it is possible that the degree of saturation of the oils affected the properties of the oleogel.
The MGC of MY at room temperature was different for each type of oil (CA = 2.5% w/w, CN = 2% w/w) (Fig. 1), this due to differences in their chemical composition (Table 1), where a composition mostly saturated in CN allows MY to retain the liquid phase more easily. However, for comparative purposes, we continued with 2.5% w/w MY in both oils in the following evaluations. It is possible that using a lower storage temperature may require a lower amount of gelator due to reduced intermolecular Brownian motion, however, a lower temperature also promotes sub-α crystallization, and consequently there is a greater likelihood of early polymorphism (Lopez-Martinez et al., 2014). The MGC values found in this work for CA and CN are lower than those reported by other authors for oils with high triolein content using a commercial monoglyceride (~3.5% w/w) (Aguilar-Zárate et al., 2019). It is known that this concentration depends on the solubility of the gelling agent in the vegetable oil, as well as the cooling rate and temperature. However, the solubility is closely linked to the solvent composition. In addition, a higher concentration of gelant results in lower solubility, which allows greater molecule-molecule interaction of the gelant, promoting self-assembly and having higher oil retention capacity.