Introduction Considering the adverse effects of saturated fatty acids and particularly trans-fats found in shortenings on human health, the development and application of oleogels in food production have become essential. Oleogelation is a valuable method for producing semi-solid and gel-like structures from trans-free unsaturated liquid oils. Nowadays, multi-component oleogels, formulated by combining high-molecular-weight and low-molecular-weight gelators, offer new horizons in the design of fat substitutes. In this context, the method of emulsifier incorporation (whether as powder or molten mixture) may significantly influence both the physicochemical properties and functional performance of the resulting oleogels. Moreover, utilizing compounds such as methylcellulose (MC) in oleogel production typically requires complex and costly methods. To overcome this, MC can be added to the molten mixture of emulsifiers and dissolved directly. The primary focus of this research is to investigate the synergistic interplay between the specific ratios of Lactic Acid Esters of Mono- and Diglycerides (LACTEM) and Diacetyl Tartaric Acid Esters of Mono- and Diglycerides (DATEM) and the structural support provided by MC. Materials and Methods This study investigated the synergistic effect of combining LACTEM with DATEM at various ratios (30:10, 10:30, 40:0, 0:40) alongside a constant amount of Distilled Monoglycerides (DMG). Furthermore, the effect of direct dissolution of MC (0% and 2%) on the textural, physicochemical, fatty acid profile, and Solid Fat Content (SFC) of the resulting oleogels was evaluated in comparison with commercial shortening. The preparation method involved melting the emulsifier blend at 70°C, followed by the direct addition and dissolution of MC at 80°C. This molten matrix was cooled at 25°C for 24 h to initiate full co-crystallization of the surfactants and the polymer. In the next step, the mixture was pulverized using a laboratory mill (spray chilling would be utilized at an industrial scale). The resulting powder was then added to liquid canola oil at a concentration of 15% (w/w). The mixture was heated to 70°C until the oil becomes completely transparent. Finally, the samples were cooled at 25°C for 24 h to form the oleogel. Results and Discussion Regarding Oil Binding Capacity (OBC), some treatments exhibited a slight decline after 30 days; however, samples containing LACTEM/DATEM and MC maintained their OBC throughout the 30-day period. In terms of textural hardness, samples containing two different ratios of LACTEM/DATEM emulsifier, with and without MC, exhibited greater similarity to the control sample. Notably, samples with the higher DATEM ratio showed no statistically significant difference compared to the shortening sample .Also, the peroxide value (PV) of the oleogel samples was significantly higher than that of the shortening sample (p < 0.001). However, the rate of PV increase during the second 15-day period was lower in all oleogel samples. Specifically, the LACTEM/DATEM10-30-MC2 sample exhibited the lowest rate of PV increase. In this sample, the peroxide value at day 30 increased by 1.93-fold compared to day 15, whereas the shortening sample showed a 5.06-fold increase in peroxide value over the same period. It should be noted that the peroxide value (PV) only reflects primary oxidation products; therefore, for a more comprehensive assessment of oxidative stability and the formation of secondary oxidation products, future studies are recommended to incorporate additional indices, such as the p-anisidine value (p-AV) or thiobarbituric acid reactive substances (TBARS). Furthermore, despite the higher solid fat content (SFC) inherent in conventional shortening, the optimized oleogels offered a superior nutritional profile, achieved through a 16.77–17.7% reduction in saturated fatty acids and almost-total elimination of trans isomers. Conclusion In conclusion, the synergistic effect of low-molecular-weight emulsifiers and methylcellulose via direct dissolution offers a viable strategy for promoting public health, as it effectively eliminates trans fats while preserving the essential functional characteristics of the lipid system.

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