## 1 Introduction  
Fat is a significant component of many food products providing energy and fat-soluble vitamins (A, D, E, and K) and contributing to food's sensory and textural properties [1]. Solid fats are used in lipid-based food formulations to provide a suitable texture, high oxidative stability, and increased shelf life. Palm oil is produced from _Elaesis guineensis_ belonging to the family of Arecaceae. This oil can provide sufficient solid oil in blends with unsaturated oils. It is a suitable source of fully natural hard fat for food products such as margarine, pastry, and shortening to provide solid fat functionality and increased stability [2]. Fat is chemically a mixture of triacylglycerol molecules. High melting point triacylglycerol molecules are crystalline at room temperature and form a three-dimensionalnetwork that can physically trap lower melting point triacylglycerolglycerol molecules in this structural framework. These crystalline TAGs contain saturated and/or trans fatty acids [3]. To produce solid fatty acids, the process of partial hydrogenation was developed with the view that hydrogenated oils are derived from healthy vegetable oils and also have lower levels of saturated fatty acids, and gradually replaced the use of animal fats in food [4]. Partially Hydrogenated Oils (PHOs) are key ingredients in margarine, shortening, and bakery products. However, these oils are a source of trans fatty acids. Over the past twenty years, clinical and epidemiological studies have shown that consumption of trans fatty acids leads to an increase in low-density lipoprotein (LDL, bad cholesterol), a decrease in high-density lipoprotein (HDL, good cholesterol), and an increase in plasma TAG levels [5]. These effects increase the risk of cardiovascular disease and insulin resistance. It is also shown that some saturated fatty acids increase plasma LDL levels when substituted for carbohydrates in the diet, although the association between saturated fatty acid intake and cardiovascular disease is still debated [6]. Despite some disagreements in the scientific community, dietary guidelines recommend reducing the consumption of saturated fatty acids and eliminating trans fatty acids. In 2015, the US Food and Drug Administration announced that, with a three-year compliance period, hydrogenated oils should be removed from the GRAS list, meaning that after 2018, this primary source of trans fatty acids will not be allowed in foods [7]. Interestingly, even after much negative publicity and rejection of such foods, they are still seen in the market. This is because trans and saturated fatty acids are responsible for the formation of the network and play an important role in the texture and mouthfeel [3]. In recent years, using various methods, scientists have modified the physical properties of oil with low viscosity to be similar to the solid and elastoplastic properties of fat. Among these, a strategy called oleogel has been developed to reduce or replace fat [8]. In these systems, the oil combines with components that alter the physical properties of the oil by various molecular interactions such as hydrogen bonding and hydrophobic interactions so that its fluidity is reduced and its rheological properties are similar to those of fat. The continuous phase of these oil gels is lipid and shows the physical properties of the hydrogel [9, 10]. Oleogels are produced by a direct method in the case of hydrophobic oleogelators such as wax, mono and diglycerides, and ethylcellulose, and by two indirect methods (using hydrophilic polymers), including emulsion and foam templated approaches [11]. Margarine or oleomargarine is food in the form of plastic or water in oil emulsion that should not contain less than 80% fat [12]. A high amount of margarine is fat (depending on the type of margarine), and the structural stability of margarine is affected by the available fat and the characteristics of the crystal network. Therefore, it is necessary to produce margarine with low saturation and desirable structural properties.