The primary intent of 21 CFR Part 113 regarding the control and testing of can seams is to prevent product adulteration due to leakage during cooling and handling after retorting. Seam defects are much like can dents in that, although the defect may be substantial, the product in the can may not be adulterated. Many variables occurring during processing and subsequent handling determine whether the defects will lead to product adulteration.
A can with a seam defect (droops, false seams, loose seams, etc.) will have a better chance of leaking but if the cooling water is chlorinated properly and the cans are handled properly after cooling, leakage and contamination still may not occur. Conversely, a can with apparently adequate seams if handled improperly, may leak and, regardless of the cooling water quality, may become adulterated.
By adulteration we mean the food consists of the filthy, putrid, or decomposed substance. It may also be adulterated if the can is swollen (even if no decomposition is noted) or leaking, since we generally consider these types of defects as rendering the food unfit for human consumption.
Because seam defects do not always lead to product adulteration, the FDA cannot support legal action against products based on seam defects only. It must be demonstrated that the product is adulterated (swollen, leaking, contains viable microorganisms or is decomposed) or other deviations from 21 CFR 113 must be documented as well as the seam defect. Therefore, the analysis of canned foods should be complete, as outlined in LIB No. 1704 and BAM, to determine if the product is adulterated. The can seam examination and microleak test serve only to document an apparent reason for the adulteration.
NOTE: No reduction in can seam evaluation during inspections or warehouse examination should be made as a result of this policy.
Continue to follow instructions in the IOM and compliance programs.