Digital image colorimetric analysis for evaluating lipid oxidation in oils and its emulsion

Optical analytical images were captured by a digital camera, and lipid peroxidation was monitored using colorimetric determination. The Image-J method was shown to have comparable accuracy to the conventional titration (American Oil Chemists' Society) and UV-Vis spectroscopic methods. Over the PV range 3-14 meq.O₂/kg, a good correlation (R² = 0.9836) was found between the proposed method and UV-Vis method with an SD of ±0.0339 meq.O₂/kg. The range and accuracy of detection were determined from the changes in the Image-J intensity values. At equivalent PV, the limit of detection was 0.175 meq.O₂/kg and the limit of quantitation was 0.35 meq.O₂/kg. The proposed Image-J application can be used to develop fast and portable devices for monitoring peroxide values. These have potential applications in quality control for small-scale farmers and small and medium enterprises.