RESEARCH OF PROPERTIES OF METAL PACKAGING MATERIALS USING MODEL CORROSION MEDIA
Corrosion of the metal packaging inner surface is one of the factors affecting the canned food quality during storage. In view of this, the corrosiveness of canned foods should be considered when choosing metal packaging. To rationalize corrosion testing, it is advisable to replace food products with model media. However, it should be borne in mind that, due to the presence in the products composition of substances that affect the corrosion rate, the corrosiveness of the model media and the product may vary. The aim of this work was to study the corrosion kinetics of tinplate in one-and two-component model media containing oxalic and citric acids, as well as in tomato paste mixed with water. The rate of uniform corrosion was measured by the polarization resistance method, pitting - zero-resistance amperometry. The measurements were carried out using an “Expert-004” corrosion meter in automatic mode. According to the results of the studies, it was found that as a model corrosion medium that mimics canned vegetables, it is advisable to use a solution containing 0.40% citric acid and 0.30% oxalic acid, because it is the most aggressive. The kinetics of tinplate corrosion during interaction with tomato paste is similar to the kinetics of the process when interacting with a two-component model medium. At the same time, the corrosiveness with respect to tinplate for tomato paste is 2.4 times less than for a model medium (8.54 and 20.46 pm /year, respectively).