Leakage Potential of Swelled Cans of Low-Acid Foods Collected from Supermarkets1

Abstract

The objective of this study was to determine the potential for leakage of swelled cans of low-acid foods. Using a vacuum leak test, 294 (38.5%) of 764 containers tested were found to have leaks. Most leakage detected by the vacuum test was located in the canner's end area (73.5%). The lap area at the side seam-double seam junction was the specific location that had the highest incidence of leakage. Can seam measurement data indicated that insufficient seam tightness was one of the primary double seam defects. It was not possible to account for double seam leakage from the individual seam measurement data. Therefore, a scoring system was developed to give a single number that included interactions of the double seam measurements. Seam measurement scores indicated that 55% of the cans had double seams of poor or questionable quality which were judged as having a potential for leakage. The results of the vacuum leak test indicated that in 26% of the cans there was potential for leakage at points other than the double seam. Therefore, a total of 81% of the swelled cans showed a potential for leakage.