Assessment of a mobile phone for use as a spectroscopic analytical tool for foods and beverages

Summary A mobile phone was used to perform optical analyses of foods and beverages. The phone’s screen served as illumination source and front view camera recorded images. Reflected intensities were used to discriminate between the different samples analysed by principal component analysis. Samples studied illustrated the technique’s potential analytical capabilities with respect to adulteration and authenticity. Three coloured additives (red, green and blue) in the concentration range 2–10 mg L−1 in a lemon lime beverage were discriminated. Adulteration by up to 25% water of milk with 3% fat content was detected with an estimated detection limit of about 3% water. Changes occurring on a green onion surface over a 48‐h ageing period at room temperature were monitored. Five different cuts from lamb carcasses weighing 9 and 14 kg were classified by the method. Considerable additional work with regard to sampling, data treatment and quantifying results is necessary before the goal of using the technique as a point‐of‐purchase analytical tool can be realised.