CORROSION RESISTANCE OF ALUMINUM CANS IN CONTACT WITH BEER

Abstract

Aluminum cans with an organic coating are used in Brazil as packaging for carbonated beverages (soft drinks, beer), which act as electrolyte solutions. These electrolytes, in contact with the inner metal can, initiate a corrosion process of aluminum. The presence of metallic ions can change the flavor of the beverage, compromising the product quality. This work aims to evaluate the corrosion resistance of aluminum in beer environment using the technique of Electrochemical Impedance Spectroscopy (EIS). The Scanning Electron Microscopy (SEM) and the Energy Dispersive Spectroscopy (EDS) were used to evaluate the metal surface. Two batches with different coating thickness were analyzed for the same date of manufacture. The electrolyte resistance and the aluminum charge transfer resistance in beer varied depending on the batch analyzed.

Keywords

• Aluminum cans; Beer; Corrosion; Electrochemical impedance spectroscopy (EIS).