When choosing metal packaging for canned tomatoes and in tomato pouring, it is advisable to take into account their corrosiveness, since corrosion of the inner surface is one of the factors affecting the quality of products during storage. To rationalize corrosion testing of metal packaging and materials, it is advisable to use model media instead of food products. It should be borne in mind that, due to the presence in the composition of products of substances that affect the corrosion rate, the corrosiveness of the model environment and the product may vary. The corrosion kinetics of canned tinplate (ELC) in tomato juice and in an aqueous solution containing oxalic and citric acid was studied. The composition of the model medium (0.4% citric acid + 0.3% oxalic acid) was selected based on the results of previous studies. The uniform corrosion rate of ELC was measured by the polarization resistance method, the pitting corrosion rate was measured by zero resistance amperometry. The measurements were carried out using an Expert-004 corrosion meter in automatic mode. The mass of the tin coating on the contact surface of the ELC is 5.5–5.7 g/m2. According to the results of the studies, it was found that the kinetics of the rate of uniform and pitting corrosion of the ELC when interacting with tomato juice is similar to the kinetics of the process when interacting with a model medium. For both the model environment and tomato juice, the corrosion process is uniform - the average stationary pitting rates are 7.5-7.6 times lower than the corresponding values for uniform corrosion (for the model environment – 2.73 and 20.46 ?m/year; for tomato juice - 1.12 and 8.54 ?m/year). At the same time, the corrosiveness with respect to ELC for tomato juice is 2.4 times less than for a model medium. Thus, it is advisable to use a two-component model medium containing 0.4% citric and 0.3% oxalic acid for corrosion testing of metal packaging and materials, taking into account the correction factor.

tinplate, corrosion rate, uniform corrosion, pitting corrosion, polarization resistance method, zero-resistance amperometry, model media, oxalic acid, citric acid, tomato juice

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