Metal containers are the major form of packing material used in the canning industry followed by plastic laminates and glass containers. Containers for thermally processed canned fishery products have several functions in common, whether they are made of metal, glass, plastic laminates or composites of plastic and metal laminates.
The functions of packaging materials can be summarized as follows:
- To hermetically seal the product in the container while delivering a thermal process which will render it "commercially sterile".
- To prevent recontamination of the product after processing and during subsequent transport and storage.
- To provide nutritional benefits and marketing convenience, through presentation of preserved fishery products all year round, often far from the source of supply, and in the majority of cases without the need to rely on refrigerated food chains.
- The most frequently used form of packaging for a canned fishery product will be Tinplate which will be fabricated in Two and Three Pieces of Cans of wide variety of shapes and sizes
- The dominant position of tin plate as the packaging material of choice for canned seafood products has been challenged with the development of aluminium alloys.
- With the exception of some fish pastes, glass is rarely used for fishery products, which are preserved by heat alone