Testing adulterated liquid-egg: developing rapid detection techniques based on colorimetry, electrochemistry, and interfacial fingerprinting

To develop rapid detection techniques for liquid eggs' adulteration, three types of adulterations were considered: water dilution, manipulation of yolk ratio in whole egg, and blending different varieties of egg white or yolk. Objective: Establish detection techniques utilizing colorimetry , electrochemistry, and interfacial fingerprinting for these adulterations, respectively. Results: Colorimetry allows for detection (1 min·sample -1 ) of water dilution through linear (R 2  ≥ 0.984) and exponential fitting (R 2  ≥ 0.992); Electrochemistry enables detection (6 min·sample -1 , R 2  ≥ 0.979) of the adulteration of yolk ratio in whole egg; Interfacial fingerprinting technique effectively detects (detection duration: 10 min·sample -1 , detection limit: 1.0–10.0 wt%) the adulteration of different varieties of egg white. Subsequently, through 3D-fluorescence microscopy (interface height variation: 22.49–573.45 μm), interfacial tension variation (65.54–35.48 mN·m -1 ), contact angle variation (89.7°–32.9°), particle size range (free water: 0.94–14.29 μm; protein aggregation: 6.57–10.76 μm), and etc., interfacial fingerprinting mechanism was elucidated. This research contributes novel insights into the detection of adulteration in liquid eggs.