Beeswax and monoglycerol-based oil foam: Effect of oil type and oleogelator concentration on physicochemical, rheological properties and storage stability
Sayed Amir Hossein Goli, Mohammad Rezvani, Maryam Abdollahi
Abstract
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.