During processing cans are subjected to extreme stress, particularly
when the hot can is cooled down rapidly from processing temperature.
The negative pressure created in the can under these conditions could
lead to micro-organisms on the container’s surface or in the cooling
water being sucked inside through a small defect in the seam. The defect
in the hot can that allowed leakage to occur may seal up and be
undetectable when the can is cool so leaker spoilage can cause cans to
blow. Since the micro-organisms enter the can after processing there is
no restriction on the type of organism capable of causing leaker spoilage,
therefore the presence of a mixed culture or non-sporing organisms is
almost certainly a result of can leakage.
Figure 4.7 The can double seam (Carnaud Metalbox)
Chapter 4 79