Beeswax and monoglycerol-based oil foam: Effect of oil type and oleogelator concentration on physicochemical, rheological properties and storage stability

Four oil types (coconut oil, rapeseed oil, sunflower oil, and flaxseed oil) and glycerol monostearate-beeswax mixture (GMS-BW; 1:1), as an oleogelator, at different concentrations (5%, 7.5%, 10%, and 12.5% w/w) were used to fabricate oil foam. Due to the higher overrun (∼38–45%) and foam stability (lower oil loss, 6–8%), intermediate firmness (∼0.55–0.60 N), and smaller bubble size (∼28 µm), sunflower oil foam (SOF) and flaxseed oil foam (FOF) containing 12.5% oleogelator were chosen for further experiments. X-ray diffraction revealed that oil type had no significant effect on polymorphism. Furthermore, FOF sample presented higher melting and crystallization enthalpy than SOF related to the stronger network confirmed by a higher G′ value (130,000 Pa) and yield stress (130 Pa) as well as its longer linear viscoelastic region (P < 0.05). Over storage time, overrun and oil loss of both samples decreased especially at room temperature, whereas firmness increased due to the further crystals' interactions.