Colour Profile, Functional Groups Characteristics and Heavy Metals of Red Food Colours Sold in Minna Main Market.

Abstract

This study assessed the functional group characteristics, colour profile and heavy metal contents of eight (8) commercial red liquid food colourant samples popularly sold in Minna markets. The brands and the package information were noted and the functional groups, colour profile and heavy metals concentrations were analysed using standard methods. The FTIR spectra revealed that all the cred colourant samples exhibited aromatic ring (C=C), hydroxyl (–OH), azo (–N=N–), sulfonate (S=O) confirming their identity as a sulfonated synthetic azo dye. Weaker sulfonate groups were also identified amongst the liquid red colourants; FCRL, ACRG and (ACRL. Red liquid colourants had higher values of brightness index than the powdered sample with colourant sample ACRG having the highest brightness index (BI). Heavy metal analysis variations in the concentrations of As, Cd, and Pb and among the samples with BDRP having the highest value of lead, cadmium and arsenic at 0.013 m/kg, 0.09 mg/kg and 0.047 mg/kg respectively. Although all concentrations were below international permissible limits, the consistent presence of these metals raises concerns regarding production quality and consumer safety. The findings underscore the need for stricter quality control and regular monitoring of food colourants in Nigerian markets to mitigate potential health risks associated with its usage.