Oil‐Assisted Thermal Processing ( OATP ) of In‐Shell Eggs: A Novel Approach Towards Functional Egg Powder Engineering

ABSTRACT Avian eggs are globally consumed, typically heat‐treated to denature proteins and enhance palatability. However, novel processing methods are required to improve the functional performance while preserving nutritional quality. This study investigated a novel oil‐assisted thermal processing (OATP) using vegetable oils as non‐polar heating media. The objective was to determine the synergistic effect of oil type and temperature on moisture loss, structural changes, and functional performance of the resulting egg albumen and yolk powders. In‐shell eggs were immersed in canola or corn oil at 100°C–170°C, freeze‐dried, and milled into powder. All treatments were performed in triplicate, and data were analyzed using one‐way ANOVA with Tukey's post hoc test ( p < 0.05). Moisture loss exhibited non‐linear temperature dependence, peaking at 130°C for canola oil (30.6%, 40–42 min) and corn oil (28.9%, 50–55 min), significantly exceeding water‐boiled eggs (2.26%, 12 min). The higher thermal conductivity of canola oil enhanced heat transfer, reducing residual moisture by 35% compared to water boiling. OATP at 100°C–150°C significantly improved the albumen powder dispersibility index (0.59–0.82) compared with water‐boiled eggs (0.22). Corn oil‐processed eggs showed lower dispersibility (0.37–0.49) but higher water rehydration capacity (4.86%–6.42%). The maximum foaming capacity (85.8%) and emulsifying activity (12.9 m 2 /g) were achieved at 130°C with canola oil. Three mechanistic regimes were identified: diffusion‐dominant (100°C–130°C), optimal denaturation (130°C), and over‐aggregation (≥ 150°C). Compared to conventional boiling, OATP offers superior temperature control, enabling tailored production of egg powders with enhanced solubility, hydration, and interfacial properties for diverse food applications.