Packaging materials for Foods
Practical Action
2. Retail containers, which protect and advertise the food for retail sale and home storage.
Examples include metal cans, glass or plastic bottles and jars, plastic tubs, pots and trays,
collapsible tubes, paperboard cartons and flexible plastic or paper bags, sachets and
overwraps.
Frequently more than one type of material is used to package a single product. For example,
display cartons may contain multiple packs of food packaged in flexible film. These in turn are
placed in corrugated board shipping boxes and loaded onto pallets.
Types of packaging materials - traditional materials
These materials have been used since the earliest times for domestic storage and local sales of
foods. However, with the exception of glazed pottery, they have poor barrier properties and are
only used to contain foods and keep them clean. They are also unsuited to the needs of
commercial production processes and are considered by many customers to be less attractive
than the newer ‘industrial’ materials described below. A summary of the main types of traditional
materials and possible current uses are as follows:
Leaves, vegetable fibres and textiles
Leaves are cheap and readily available, and are used as
wrappers for products such as cooked foods that are
quickly consumed. Banana or plantain leaves are used
for wrapping traditional cheese and fruit confectionery
such as guava cheese. Maize leaves are used to wrap
corn paste or blocks of brown sugar, and 'Pan' leaves
are used for wrapping spices in India. Other examples
are green coconut palm, papyrus leaves and bamboo
and rattan fibres, which are woven into bags or baskets
and used for carrying meat and vegetables in many
parts of the world. Palmyra palm leaves are used to
weave boxes in which cooked foods are transported,
and small banana leaf bags are used to contain coffee
Fig. 2. Traditional leaf packaging
of coffee beans. (Photo: Peter
Fellows)
beans (Fig. 1) that are a traditional gift in some parts of Africa. Some of these have the potential
to be developed as niche packaged products for tourist markets.
Fibres from kenaf and sisal plants are mainly used for making ropes, cord and string, which can
be made into net bags to transport hard fruits. They can also be spun into a yarn that is fine
enough to make coarse canvas. Other examples of textile containers are woven jute sacks, which
are used to transport a wide variety of bulk foods including grain, flour, sugar and salt. Plant
fibre sacks are flexible, lightweight and resistant to tearing, have good durability, and may be
chemically treated to prevent them rotting. Their rough surfaces are non-slip, which makes
stacking easier compared to synthetic fibre sacks, and they are bio-degradable. Most textile
sacks can be re-used several times after washing and they are easily marked to indicate the
contents. They are still widely used to transport fresh or dried crops, but they are being replaced
as shipping containers by woven polypropylene or multi-walled paper sacks (below). Calico is a
closely woven, strong cotton fabric that can be made into bags for flour, grains, legumes, coffee
beans and sugar. Methods of filling and sealing sacks and bags are described in Technical Brief:
Filling and Sealing Packaged Foods. Muslin and cheesecloth are open-mesh, light fabrics used
both to strain liquid foods during processing and to wrap foods such as cheeses and processed
meats (e.g. smoked ham).
Wood
Wooden containers protect foods against crushing, have good stacking characteristics and a good
weight-to-strength ratio. Wooden boxes, trays and crates have traditionally been used as shipping
containers for a wide variety of solid foods including fruits, vegetables and bakery products.
Wooden tea chests are produced more cheaply than other containers in tea-producing countries
and are still widely used. However, in most applications, plastic containers have a lower cost, are
more easily cleaned for reuse, do not risk contaminating foods with splinters, and they have
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