A method of monitoring and optimizing the concentration of an additive composition in a fuel ethanol and determining total ethanol content in a fuel ethanol composition, the additive composition comprising a denaturant combined with a corrosion inhibitor the method comprising: (a) adding an inert fluorescent tracer to the corrosion inhibitor to form a traced corrosion inhibitor formulation, the traced corrosion inhibitor formulation is then combined with the denaturant to form the additive composition; (b) adding a known amount of the additive composition to the fuel ethanol to create a treated fuel ethanol, wherein the known amount is calculated to provide an optimum concentration range for the additive composition in the treated fuel ethanol, and wherein the inert fluorescent tracer is Rhodamine B base; c) measuring the fluorescent signal for the inert fluorescent tracer in the treated fuel ethanol at a point subsequent to adding the known amount of the additive composition; (d) determining the concentration of the additive composition in the treated fuel ethanol based upon the measured fluorescent signal of the inert fluorescent tracer at the point subsequent; (e) if the determined concentration of the additive composition is above the optimum concentration range, diluting the treated fuel ethanol by adding a known additional volume of the fuel ethanol, wherein said additional volume is calculated to bring the concentration of the additive composition in the treated fuel ethanol into the optimum concentration range; and (f) if the determined concentration of the additive composition is below the optimum concentration range, adding an additional known amount of the additive composition, wherein said additional known amount is calculated to bring the concentration of the additive composition in the treated fuel ethanol into the optimum concentration range, wherein the treated fuel ethanol is mixed with gasoline to form a fuel ethanol composition and wherein the fluorescent signal is used to determine total ethanol content in the fuel ethanol composition. (a) adding an inert fluorescent tracer to the corrosion inhibitor to form a traced corrosion inhibitor formulation, the traced corrosion inhibitor formulation is then combined with the denaturant to form the additive composition; (b) adding a known amount of the additive composition to the fuel ethanol to create a treated fuel ethanol, wherein the known amount is calculated to provide an optimum concentration range for the additive composition in the treated fuel ethanol, and wherein the inert fluorescent tracer is Rhodamine B base; c) measuring the fluorescent signal for the inert fluorescent tracer in the treated fuel ethanol at a point subsequent to adding the known amount of the additive composition; (d) determining the concentration of the additive composition in the treated fuel ethanol based upon the measured fluorescent signal of the inert fluorescent tracer at the point subsequent; (e) if the determined concentration of the additive composition is above the optimum concentration range, diluting the treated fuel ethanol by adding a known additional volume of the fuel ethanol, wherein said additional volume is calculated to bring the concentration of the additive composition in the treated fuel ethanol into the optimum concentration range; and (f) if the determined concentration of the additive composition is below the optimum concentration range, adding an additional known amount of the additive composition, wherein said additional known amount is calculated to bring the concentration of the additive composition in the treated fuel ethanol into the optimum concentration range, wherein the treated fuel ethanol is mixed with gasoline to form a fuel ethanol composition and wherein the fluorescent signal is used to determine total ethanol content in the fuel ethanol composition. <EOS>