Oleogelation: current developments and perspectives to lipid-based oil structuring

Oleogelation is an efficient oil-structuring technique commonly utilized to form oleogels using vegetable oil. This chapter aims to summarize current developments in the production of oleogels by structuring liquid oil with the help of lipids. The structuration occurs through oleogelators that are classified as high-molecular- and low-molecular-weight oleogelators (LMOGs). LMOGs, importantly waxes, can form a three-dimensional network within the oil at a low concentration (1%–3% w/w). Wax-based oleogels form through the direct dispersion method, giving rise to crystallite formation. The process of oleogel crystallization is similar to fat crystallization, which occurs in three stages, including nucleation, crystal growth, and polymorphic transition. Emulsifiers are amphiphilic molecules that often affect the stages of crystallization in oleogels. The effect of emulsifiers comes from the organization of crystals during the crystallization stages. Majorly the formulated oleogels are characterized through different microscopic studies, molecular characterization, and thermal studies. The field of oleogels has evolved quite progressively since 1960, which has been highlighted in this review through the bibliometric study. The study also confirmed the potential applications of the oleogels highlighting the field of novel delivery systems for drug and nutrient delivery along with their use in replacing saturated solid fat without compromising the organoleptic properties.