JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY, vol.64, no.28, pp.5767-5772, 2016 (SCI-Expanded)
Total chlorine in milk was determined via the molecular absorption of diatomic strontium monochloride at 635.862 nm using high-resolution continuum source graphite furnace atomic absorption spectrometry. The effects of coating the graphite furnace, using different modifiers, amount of molecule-forming element, and different calibrants were investigated and optimized. Chlorine concentrations in milk samples were determined in a Zr-coated graphite furnace using 25 mu g of Sr as the molecule-forming reagent and applying a pyrolysis temperature of 600 degrees C and a molecule -forming temperature of 2300 degrees C. Linearity was maintained up to 500 mu g mL(-1) of Cl. The method was tested by analyzing a certified reference wastewater. The results were in the uncertainty limits of the certified value. The limit of detection of the method was 1.76 mu g mL-1. The chlorine concentrations in various cow milk samples taken from the market were found in the range of 588-1472 mg L-1.