Packaging materials for Foods
Practical Action
largely replaced wooden containers in most applications. Small wooden boxes are used to pack
tea or spices for tourist markets in some countries. Wooden barrels have been traditionally used
as shipping containers for a wide range of liquid foods, including cooking oils, wine, beer and
juices. They continue to be used for some wines and spirits because flavour compounds from the
wood improve the quality of the products, but in other applications have been replaced by
aluminium, coated steel or plastic barrels.
Leather
Leather containers made from camel, pig or kid goat hides have traditionally been used as
flexible, lightweight, non-breakable containers for water, milk and wine. Manioc flour and
solidified sugar were also packed in leather cases and pouches, but the use of leather has now
ceased for most commercial food applications.
Earthenware
Pottery is still used domestically for storage of liquid and solid foods such as yoghurt, beer, dried
foods, honey, etc.. Corks, wooden lids, wax or plastic stoppers, or combinations of these are used
to seal the pots. If they are glazed and well sealed, they prevent oxygen, moisture and light from
entering the food and they are therefore suitable for storing oils and wines. They also restrict
contamination by micro-organisms, insects and rodents. Unglazed earthenware bowls or pots are
porous and the evaporating moisture makes them suitable for products that need cooling. They
are still used for local sales of curd or yoghurt in parts of Asia.
Glass or plastic containers have largely replaced pottery because of its high weight, fragility,
variability in volume when hand-made, and the difficulty of adequately cleaning pottery
containers for re-use.
Types of packaging materials - industrial materials
These materials have been developed over the last 200-300 years and are the main types of
packaging used by small-scale food processors. The availability of glass, metal or plastic
containers varies considerably in different countries, and this, together with the relative cost of
different materials, determines their uptake by local processing industries. Where these materials
have to be imported, large minimum order sizes can be a significant constraint on the
development of a processing sector.
Metal containers
There are two basic types of metal cans: those that are sealed using a ‘double seam’ and are
used to make canned foods (see Technical Brief: Canning of Foods); and those that have push-on
lids or screw-caps that are used to pack dried foods (e.g. milk or coffee powder, dried yeast) or
cooking oils respectively. Double-seamed cans are made from tinplated steel or aluminium and
are lined with specific lacquers for different types of food. Cans have a number of advantages
over other types of container: when sealed with a double-seam they provide total protection of
the contents; they are tamperproof; and they can be made in a wide range of shapes and sizes.
However, the high cost of metal and the high manufacturing costs make cans expensive
compared to other containers. They are heavier than plastic containers and therefore have higher
transport costs. There are few can-making factories in developing countries and small-scale food
processors generally do not use metal cans because of these disadvantages and/or lack of
availability. Larger (200 litre) metal drums are widely used as shipping containers for oils, juices
and other liquid foods, although cheaper plastic drums are steadily replacing them.
Other types of metal containers include aluminium foil cups and trays, laminated foil pouches as
alternatives to cans or jars, collapsible aluminium tubes for pastes, and aluminium barrels. The
advantages of aluminium are that it is impermeable to moisture, odours, light and micro-
organisms, and is an excellent barrier to gases. It has a good weight:strength ratio and a high
quality surface for decorating or printing.
Glass
Glass bottles and jars have some of the advantages of metal cans: they are impervious to micro-
organisms, pests, moisture, oxygen and odours; they do not react foods or have chemicals that
migrate into foods; they can be heat processed; they are recyclable, and (with new lids) they are
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