Chemical Taint in Rindless Gouda Cheese

Abstract

The compound 2-bromo-4-methylphenol was identified as being responsible for a “chemical (phenolic)” taint in brine-salted Gouda cheese manufactured over a 3 month period. The concentration on the surface of cheese manufactured at the beginning of the period was determined to be between 14 and 25 μg/kg (ppb) decreasing to between 1 and 2 μg/kg at the end. It was proposed that 4-methylphenol and active bromine could be the precursors. Attention focused on the brine, which was shown to be a source of 4-methylphenol and a potential source of bromine. Irradiation of the brine with UV light and dosing with sodium hypochlorite solution were considered to be important factors in generating active bromine. Experiments, carried out in model systems, demonstrated that 2-bromo-4-methylphenol could be generated from sodium bromide and 4-methylphenol in the presence of either UV light or sodium hypochlorite, but not in their absence. Keywords: Chemical taint; Gouda cheese; brine salting taint; 2-bromo-4-methylphenol