The number of publications, as a result of searching for hydrogels and oleogels for food applications in the last 10 years, shows that oleogels are getting more attention while hydrogels remain as a topic of interest. Moreover, the increasing number of publications dealing with food and obesity reveals that the food industry still has an important role in this regard.

Oleogels are semi-solid materials containing a large fraction of liquid oil entrapped in a network of structuring molecules. In the food industry, these formulations can be used to mimic fats and to deliver bioactive compounds. In the last decade, there has been increasing interest in these structures, not only from a scientific point of view, i.e., studying new molecules, methodologies for gelification, and new structures, but also from a technological point of view, with researchers and companies exploring these structures as a way to overcome certain challenges and/or create new and innovative products. One of the exciting applications of oleogels is the delivery of functional molecules, where the incorporation of oil-soluble functional compounds can be explored not only at the macroscale but also at micro- and nanoscales, resulting in different release behaviors and also different applications. This review presents and discusses the most recent works on the development, production, characterization, and applications of oleogels and other oleogel-based systems to deliver functional molecules in foods.

This study was aimed at evaluating the physical conformation and oxidative stability of beeswax oleogels when fortified by the incorporation of β-carotene (complex-beeswax oleogels). Rheological evaluation showed the presence of a strengthened structural conformation in the oleogels with β-carotene in comparison with that in oleogels without β-carotene; this was verified by the increase in rheological parameters. Small angle X-ray scattering data show that the lamellar crystal structure of the oleogels with β-carotene exhibits similar d-spacings and lower radius of gyration (R_g) values for all concentrations due to the stronger oleogel network. X-ray diffraction measurements provide useful information on the crystal polymorphism type and arrangement of the internal lamellar phases of the crystals. Oil binding capacity is also affected by the incorporation of β-carotene into the oleogel and proven to be higher for the complex-beeswax oleogels, which enhances the ability of the oleogels to retain an oil phase within their crystalline network. The oxidative profiles of the complex-beeswax oleogels were studied during storage, and beeswax at the concentrations of 4, 6, and 8% revealed higher oxidative stability than that at the concentration of 2%. In this study, the possibility of tailoring the properties of oleogels is demonstrated considering the foreseen applications of oleogels in food products, such as in texturizers, as well their capacity to deliver bioactives and thus add value to food products.