Porosity and discontinuity of food can protective coatings - simple chemical tests and serious consideration
In order to protect food cans against corrosion, tin coatings and lacquers are employed for internal and external protection. Coating porosity and discontinuity are practical problems in the food canning industry. The prevention of these problems lies in the timely observation and analysis of the scale that can arise in the production of food cans after filling and thermal processing. In this paper, we discuss results of two referenced simple chemical methods (sulphur dioxide and copper sulphate tests) for examining the porosity and discontinuity of food can protective coatings (tin and lacquer layers). In some specific cases, the tests showed precise locations of defects invisible to the eye.