Fabrication and characterization of oleogels structured by phycocyanin/fucoidan/xanthan gum co-stabilized by beeswax...

Application of hydrophilic biopolymers to structure the oil through oleogelation can be accomplished using indirect methods. Accordingly, in the present study, foam-templated oleogel based on phycocyanin (PC), fucoidan, and xanthan gum (XG), co-stabilized by beeswax, was fabricated. The results showed that PC had a remarkable capacity to form foam. Also, on account of XG inclusion, stable foams, in which air bubbles were spherical in shape, were obtained. Cryogels (i.e., dried foams) could be formed without structural collapse after the freeze-drying process. They had oil absorption capacities of 68-84 times their own weights. Fucoidan had a positive contribution to the foaming capacity, cryogel density, and oil absorption capacity. All oleogels, co-stabilized by beeswax, were solid-like without oil leakage. The rheological properties, including amplitude, frequency, and temperature sweep tests, as well as parameters obtained from them, like parameters related to LVR (e.g., G'_LVR, tan δ_LVR, and yield point), Power law model, weak gel model, and Arrhenius model, represented different responses in terms of XG concentration and presence of fucoidan. By examining Fourier transform-infrared spectra, rearrangements in the secondary structure of the protein part in PC owing to the aeration and occurrence of van der Waals interactions were perceived for cryogels and oleogels, respectively. This study provides insights into the fabrication and characterization of PC/fucoidan/XG-based oleogels, and the results suggest the application of PC, fucoidan, and XG for oil structuring purposes.