Assessment of oleogels as a delivery method of curcumin in yellow cake

Abstract: The increasing rate of non-communicable diseases is the primary concern of food scientists to reduce saturated fat consumption and increase the bioavailability of bioactive compounds. This experiment aimed to assess the oxidative stability of curcumin-loaded oleogels and apply them in yellow cake preparation. First, 40 oleogel samples were prepared with 2%, 4%, 6%, and 10% of rice bran (RB) and carnauba (CN) waxes and 0%, 0.1%, 0.2%, 0.4%, and 0.8% curcumin (Cr) in corn oil as the continuous phase. Then oxidative stability of the oleogel samples was evaluated by measuring their peroxide values (PV) at 0, 7, 14, and 28 days under an accelerated oxidative study at 60° C. Results showed that after 28 days of storage, among the RB added samples S4 (RB10%, Cr0%), and S10 (RB4%, Cr0.2%) had the lowest PV, which were 154.33 ± 18.58, and 127 ± 5 meqO2/kg, respectively. On the other hand, among the CN oleogels, S35 (CN6%, Cr0.4%), and S40 (CN10%, Cr0.4%) showed the lowest PV, which were 167.66 ± 4.04, and 191 ± 6.24 meqO2/kg, respectively. As the amount of wax increases, the oleogelator’s ability to solidify liquid corn oil becomes stronger, and the network structure becomes more stable. This strong wax network entraps and immobilizes oil, reducing oil and oxygen interaction. Moreover, curcumin (polyphenol) acts as an antioxidant by transferring a hydrogen (H) atom to the reactive species. Thus, four samples (S4, S10, S35, and S40) were selected for the yellow cake preparation and compared with the control cake sample. The RB added oleogel was a better delivery method of curcumin and fat replacer in the cake than the CN oleogel. However, this bioactive compound is poorly water-soluble; hence it shows low bioavailability. In that case, oleogel could be a breakthrough as a delivery method of curcumin to increase its absorption.