Oleogel-based frying medium: influence of rice bran wax-canola oil oleogel on volatile profile in fried fish fillets

Oleogelation has proven to be a successful strategy for structuring oils. In recent years, the use of oleogels as a deep frying medium has gained popularity as an effective approach to minimise oil uptake and reduce the energy content of fried foods. This study was designed to evaluate an oleogel matrix consisting of rice bran wax and canola oil, prepared by oleogelation technique, as a deep frying medium. Two types of the oleogels (CRBO-3 with 3 g wax/100 g oil; CRBO-6 with 6 g wax/100 g oil) were formulated and these oleogels were tested as a frying medium for fish fillets. The prepared oleogels were compared with refined canola oil (CO, control) and evaluated for both the frying stability of the oils and the volatile profile of the fried fish fillets. In particular, differences were observed in the crystallization and melting profiles of oleogels before and after frying. Lower levels of total polar material, peroxide value and trans fatty acids contents were noticed in fish fillets fried in the oleogels. An increase in wax concentration had an impact on the volatile profile of fish fillets and lead significant increases in p-xylene, pentene-3-ol and nonanoic acid. In general, oleogel-based frying medium contributed to the formation of characteristic fish fillet including aroma notes of pineapple, balsamic and honey when compared to fish fried in refined canola oil. The findings suggest oleogels as an alternative frying medium for fish with reduced calorie value and improved aromatic quality.