Determination of Impurity Content in Oily Mill Fluids Using Smartphone-Based Technology

The production of olive oil inherently involves the handling of various oily fluids which, depending on the stage of the process, may contain impurities capable of affecting the physicochemical and sensory properties of the final product. Considering this, the detection, quantification, and removal of such substances should be prioritised to ensure the production of a high-quality product. Against this background, this study investigates the potential of using smartphones to predict the impurity content (C) in olive oil. Such devices are noteworthy for their ability to capture and analyse images with high precision, offering a viable alternative to conventional colorimeters. The proposed method encompasses sample preparation, the design of a smartphone-compatible image acquisition system, and the processing of colorimetric coordinates using linear estimation models. One of the most notable findings of this research is that the present approach, which was developed using a low-cost design, is able to estimate the value of the impurity content in oily fluids with an error on the order of 0.07% when C is below 2%.