Determination of content and antioxidant capacity of natural food colors E160a and E160d in ketchup

After potato, tomato (Solanum lycopersicum) is the world?s second-largest vegetable crop. More than 80% of tomato consumption comes from processed products such as ketchup, tomato juice, pickled tomatoes, sauces, paste, pur?e. Samples of mild ketchup from two different manufacturers (A and B) were selected for the analysis of the content of natural food colors E160a and E160d. Using a UV-Vis spectrophotometric method and Lambert-Beer law, a system of two linear equations with two unknowns was set up, which was used to determine the concentrations of colors E160a and E160d. The antioxidant capacity of the two selected samples was determined using the DPPH assay. The obtained results indicated that the content of colors E160a and E160d was higher in the sample of ketchup B. Also, the DPPH assay showed that the sample of ketchup B had a higher antioxidant capacity.