Recent Advances in Understanding and Use of Oleofoams

Abstract

This review aims at presenting recent advancements on the understanding of oleofoams for food applications. Edible oleofoams are currently based on heating a vegetable oil solution containing a high-melting point component, which crystallize upon cooling. After aeration (mostly by whipping), crystals adsorb to air bubble surfaces. The remaining crystals in excess in the continuous phase form an oleogel. Due to both the presence of crystals at the interface and in the bulk, the resulting oleofoams exhibits high stability to drainage, coalescence, and disproportionation. The mechanisms leading to the high foam stability are still under investigations to understand and to discriminate between bulk and interfacial rheology effects. The research on edible oleofoams are still scarce in comparison to aqueous food foams even if they present promising applications. In the area of molecular gastronomy, oleofoams are already produced. Oleofoams are a great opportunity for food technologists to develop healthier food products with a low fat content associated to new sensorial properties. However, it is important to better understand these systems in order to help food technologists to use oleofoams and it will contribute to expand this new promising area in food science.

Edible oleogels as solid fat alternatives: Composition and oleogelation mechanism implications

“…Oleofoams can be developed by whipping the crystalline structures of oleogels (Fameau & Saint‐Jalmes, 2017). In oleofoams, the crystals absorb air bubbles after aeration and form oleogels in the continuous phase (Fameau & Saint‐Jalmes, 2020). Research with water in oleogel emulsion have suggested that the stabilization of the emulsion is through the 3‐dimensional crystalline network of oleogels immobilizes the dispersed water droplets or the Pickering effect (García‐Ortega et al., 2021; Wijarnprecha et al., 2019).…”

Recent progress in Pickering emulsions stabilised by bioderived particles

“…Oleofoams are much less common than their aqueous-based foam counterparts, with the low surface energy at the air–oil interface making them more difficult to prepare. 116 However, they have received increased interest in recent years, particularly in the food industry as they can provide a reduced calorific content whilst still giving an aerated, smooth texture with similar rheological properties to their full-fat counterparts. 112 Also, in contrast to aqueous foams, the lack of water present leads to less microbial spoilage with less requirement for preservatives.…”

“… 112 Also, in contrast to aqueous foams, the lack of water present leads to less microbial spoilage with less requirement for preservatives. 116 Research is restricted by the polymorphism and concentrations of fat crystals chosen to investigate since below a certain concentration, the crystals provide insufficient coverage to stabilise the air within the oil whereas above the optimal range, the oleogel becomes too difficult to aerate.…”

Foaming and antifoaming in non-aqueous liquids

“…Further information on particle stabilization can be found in reviews by Fameau and Saint-Jalmes [73], and Binks et al [76]. Applications of particle based foam stabilization in food science and other non-petroleum industry applications can be found in a recent review by Fameau et al [84].…”