Because of the metal packaging corrosion, during storage of canned food the quality deteriorates.One of the ways to reduction of quality loss and increase the shelf life of canned products is the use of food additives - corrosion inhibitors. From the literary data it is known that pectin and gelatin are corrosion inhibitors whose action is based on adsorption to the metal surface.Besides the usual gelatin, in the work we used hydrolyzed gelatin, which does not increase in the viscosity of the liquid phase.The aim of the present work was to study the effect of pectin, gelatin and hydrolysed gelatin on the tinplate corrosion rate in the liquid phase of stone fruit compotes (cherries, merries, peaches and plums). The corrosion rate was measured by the method of linear polarization resistance, based on the creating a potential difference between two identical samples of metal and measuring the amperage.The measurements were carried out using the universal automatic corrosion-meter "Expert-004".For all corrosive media, the corrosion rate kinetics is as follows: at the beginning of the test, the maximum corrosion rate of tinplate is observed, which decreases to a stationary value within 24-36 hours. The presence of inhibitors has not effect the kinetics of the process, but the steady-state corrosion rate for the liquid phase of compote from cherries decreased 1.6 - 3 times, for the liquid phase of compote from peaches - by 1.9 times.For the liquid phase of compotes from merries and plums, the application of pectin and hydrolysed gelatin does not has an inhibitory effect.The greatest inhibitory effect for the liquid phase of compotes from cherries is observed when applying 0.5% hydrolyzed gelatin - without an inhibitor, the steady-state corrosion rate of tinplate was 8.3 ?m / year, with the inhibitor - 2.8 ?m / year. According to the results of the study, it was found that in order to reduce quality losses during the storage of stone fruit compotes in a metal package, it is advisable to apply hydrolyzed gelatin in an amount of 0.5% to the mass of the liquid phase.

metal packing, electrolytic tinplate, corrosion rate, corrosion inhibitors, pectin, gelatin, hydrolyzed gelatin, polarization resistance method, compotes

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