Valorization of Pangasius byproduct oil in wax-structured oleogels as a potential butter substitute for reduced-fat chocolate-based products

Abstract

Despite the extensive use of various vegetable oils in oleogel development, sustainable sources, such as belly Pangasius oil derived from industrial byproducts, offer a promising alternative as the liquid phase in oleogel systems. This research aimed to determine the optimal type and concentration of rice bran wax (RBW) and candelilla wax (CW) oleogelators based on Pangasius byproduct oil and to evaluate their application in producing reduced-fat chocolate-based products. The selected oleogel systems were further assessed, and the properties of the resulting chocolate products were characterized. The 5% CW oleogel exhibited superior gelling and oil binding capacity (99.86 ± 0.13%). Differential scanning calorimetry of oleogels with 2.5%, 5%, and 7.5% oleogelator concentrations showed a shift in melting points with increasing temperature. Rheological analysis revealed dynamic changes in G' and G" values as the oleogelator concentration increased. Application of the 5% CW oleogel yielded optimal results, producing chocolate products with physical and sensory characteristics comparable to those made with commercial butter. Substituting 50% of the butter with oleogel resulted in products with similar physical attributes and sensory acceptance. Hedonic testing showed no significant differences in most parameters across substitution levels (p > 0.05), with an average acceptance score exceeding 7 on a 9-point scale. Notably, the total energy content of the chocolate product was reduced by 43.77% with 100% oleogel substitution. Eventually, this proof of concept highlights the potential of Pangasius byproduct oil as a sustainable liquid phase in oleogel technology, opening new possibilities for its application in confectionery.