title: Smart Nonaqueous Foams from Lipid-Based Oleogel.
abstract: Oil foams are composed of gas bubbles dispersed in an oil phase. These systems are scarcely studied despite their great potential in diverse fields such as the food and cosmetic industries. Contrary to aqueous foams, the production of oil foams is difficult to achieve due to the inefficiency of surfactant adsorption at oil-air interfaces. Herein, we report a simple way to produce oil foams from oleogels, whose liquid phase is a mixture of sunflower oil and fatty alcohols. The temperature at which the oleogel formed was found to depend on both fatty alcohol chain length and concentration. The air bubbles in the oleogel foam were stabilized by fatty alcohol crystals. Below the melting temperature of the crystals, oleogel foams were stable for months. Upon heating, these ultrastable foams collapsed within a few minutes due to the melting of the crystal particles. The transition between crystal formation and melting was reversible, leading to thermoresponsive nonaqueous foams. The reversible switching between ultrastable and unstable foam depended solely on the temperature of the system. We demonstrate that these oleogel foams can be made to be photoresponsive by using internal heat sources such as carbon black particles, which can absorb UV light and dissipate the absorbed energy as heat. This simple approach for the formulation of responsive oil foams could be easily extended to other oleogel systems and could find a broad range of applications due to the availability of the components in large quantities and at low cost.
authors.affiliation: Biopolymères Interactions Assemblages, INRA, Rue de la Géraudière, 44316 Nantes, France.
authors.forename: Anne-Laure
authors.initials: AL
authors.lastname: Fameau
authors.affiliation: Department of Chemical and Biomolecular Engineering, North Carolina State University , Raleigh, North Carolina 27695, United States.
authors.forename: Stephanie
authors.initials: S
authors.lastname: Lam
authors.affiliation: Biopolymères Interactions Assemblages, INRA, Rue de la Géraudière, 44316 Nantes, France.
authors.forename: Audrey
authors.initials: A
authors.lastname: Arnould
authors.affiliation: Biopolymères Interactions Assemblages, INRA, Rue de la Géraudière, 44316 Nantes, France.
authors.forename: Cédric
authors.initials: C
authors.lastname: Gaillard
authors.affiliation: Department of Chemical and Biomolecular Engineering, North Carolina State University , Raleigh, North Carolina 27695, United States.
authors.forename: Orlin D
authors.initials: OD
authors.lastname: Velev
authors.affiliation: Institut de Physique de Rennes, UMR CNRS 6251-Université Rennes 1, 35000 Rennes, France.
authors.forename: Arnaud
authors.initials: A
authors.lastname: Saint-Jalmes
mesh_terms: D005233:Fatty Alcohols / Q000737:chemistry*; D008055:Lipids / Q000737:chemistry*; D009930:Organic Chemicals / Q000737:chemistry; D010316:Particle Size; D010938:Plant Oils / Q000737:chemistry*; D000074242:Sunflower Oil; D013499:Surface Properties; D013696:Temperature
chemical_list: D005233:Fatty Alcohols; D008055:Lipids; D009930:Organic Chemicals; D010938:Plant Oils; D000074242:Sunflower Oil; C016021:oleogels