SOP: Sampling of Cans for Spoilage Examination

GIFSQ — Global Institute for Food Safety & Quality

Principle

A sterility result on one can applies only to that can, not to the whole batch. Unless spoilage is widespread, many cans must be taken to have any chance of finding it, and the number depends on the spoilage pattern: widespread spoilage needs only a few cans plus controls, suspected underprocessing needs a moderate set from each batch, and leaker spoilage — which touches very few cans — needs as many cans as can be examined.

Apparatus required

• None beyond the cans themselves

Procedure

Decide which sampling plan fits the spoilage pattern

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If the spoilage is widespread and the cans are blown or swollen, examine six blown or swollen cans and six sound cans drawn from a different batch to act as controls

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If underprocessing is suspected, examine 6–12 cans from each batch

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If leaker spoilage is suspected, examine as many cans as possible, since it is likely to occur in only a very small number of cans in a batch

Precautions

• A negative result on a particular sample is significant only for that sample — never extend it to the batch.
• Keep the control cans separate from the suspect cans at every stage.

References

Ranganna, S., Handbook of Analysis and Quality Control for Fruit and Vegetable Products, 2nd edition.