Sunflower Oil–Beeswax Oleogels and Bigels Enriched With Quercetin‐Rich Onion Phenolics for Biscuit Fat Replacement: Physicochemical, Antioxidant, and Stability Outcomes

This study evaluated sunflower oil-beeswax oleogels (OLGL) and bigels (BGL) as fat replacers in biscuits and introduced a phenolic-enriched bigel (BGLX) using a quercetin-rich onion extract. Converting the oleogel to a bigel softened the network and lowered thermal transitions (firmness: 4.37-3.77 N; melting point: 55.4°C-48.4°C for OLGL and BGL, respectively), with only minor, non-significant additional softening in BGLX. Oil binding capacity decreased relative to OLGL (78.35%) in bigels (73.17% BGL; 72.57% BGLX). Phenolic enrichment increased antioxidant capacity in gels (TPC: 3.95-5.62 mg GAE/g; DPPH: 28.15%-39.73% from sunflower oil to BGLX, respectively) and raised thermal resistance (DSC Td: ~229°C to ~248°C for BGL and BGLX, respectively). In biscuits, structured lipids maintained processing functionality and increased moisture retention, with protein and ash unchanged. At Day 0, oxidative status was similar among structured-lipid biscuits; during 90-day ambient storage, peroxide growth was attenuated stepwise and remained within Codex limits (control 8.07 vs. BGLX 4.54 meq O₂/kg). AFM/SEM showed smoother networks in OLGL and rougher, more complex features in bigels, consistent with dual-phase structuring. Practically, bigels enable lower-saturated-fat bakery reformulation, and phenolic enrichment offers an additional, clean-label route to oxidative stability without penalizing texture.