Introduction to Food Wastage

                                         Introduction to
Food Wastage

                                    (http://en.wikipedia.org/wiki/Food_waste)   (07.10.2013)

Food
waste
or food loss is food material that is discarded or unable to be used.
Various political organisations and entities have their own definition of what
constitutes food waste. The causes of wasted food are numerous, and occur at
the stages of production, processing, and retailing.

As of 2011,
1.3 billion tons of food,  about one
third of the global food production, are lost or wasted annually. Loss and
wastage occurs on all steps in the food supply chain.  In low-income countries, most loss occurs
during production, while in developed countries much food – about 100 kilograms
(220 lb) per person and year – is wasted at the consumption stage.

Production

In developing and developed
countries which operate either commercial or industrial or agriculture, food
waste can occur at most stages of the food industry and in significant amounts. In subsistence agriculture    , the amounts of food waste are unknown,
but are likely to be insignificant by comparison, due to the limited stages at
which waste can occur, and given that food is grown for projected need as
opposed to a global marketplace demand. Nevertheless, on-farm losses in storage
in developing countries, particularly in African countries, can be high
although the exact nature of such losses is much debated.

Research into the food industry of
the United States  whose food supply is
the most diverse and abundant of any country in the world, found food waste
occurring at the beginning of food production. From planting, crops can be
subjected to pest infestations and severe weather, which cause losses before
harvest. Since natural forces (e.g. temperature and precipitation) remain the
primary drivers of crop growth, losses from these can be experienced by all
forms of outdoor agriculture. The use of  machinery in harvesting can cause waste, as
harvesters may be unable to discern between ripe and immature crops, or collect
only part of a crop. Economic factors, such as regulations and standards for
quality and appearance, also cause food waste; farmers often harvest selectively,
preferring to leave crops not to standard in the field (where they can be used
as fertilizer or animal feed), since they would otherwise be discarded later.

Food
processing

Food waste continues in the post
harvest stage stage, but the amounts of post-harvest loss  involved are relatively unknown and difficult
to estimate. Regardless, the variety of factors that contribute to food
waste, both biological/environmental and socio economic losses  would limit the usefulness and reliability of
general figures. In storage, considerable quantitative losses can be attributed
to pests and microorganisms. This is a particular problem for countries that
experience a combination of heat (around 30°C) and ambient humidity (between 70
and 90 per cent), as such conditions encourage the reproduction of insect pests
and micro-organisms. Losses in the nutritional value, calorific value and
edibility of crops, by extremes of temperature, humidity or the action of
micro-organisms, also account for food waste; these “qualitative losses”
are more difficult to assess than quantitative ones. Further losses are
generated in the handling of food and by shrinkage in weight or volume.

Some of the food waste produced by
processing can be difficult to reduce without affecting the quality of the
finished product. Food safety regulations  are able to claim foods which contradict
standards before they reach markets. Although this can conflict with efforts to
reuse food waste (such as in animal feed), safety regulations are in place to
ensure the health of the consumer; they are vitally important, especially in
the processing of foodstuffs of animal origin (e.g. meat and dairy products),
as contaminated products from these sources can lead to and are associated with
micobiological and chemical hazards.

Retail

Packaging protects food from damage during its transportation from
farms and factories via warehouses to retailing, as well as preserving its
freshness upon arrival.^] Although it
avoids considerable food waste, packaging can compromise efforts to reduce food
waste in other ways, such as by contaminating waste that could be used for
animal feedstocks.

Retail stores can throw away large
quantities of food. Usually, this consists of items that have reached their
either their best before, sell by or use-by dates. Food that passed the best before, and sell-by date, and
even some food that passed the use-by date is still edible at the time of
disposal, but stores have widely varying policies to handle the excess food.
Some stores put effort into preventing access to poor or homeless people, while
others work with charitable organizations to distribute food. Retailers also
contribute to waste as a result of their contractual arrangements with
suppliers. Failure to supply agreed quantities renders farmers or processors
liable to have their contracts cancelled. As a consequence, they plan to
produce more than actually required to meet the contract, to have a margin of
error. Surplus production is often simply disposed.

Extent

Global
extent

The 2011 SIK study estimated the
total of global food loss and waste to around one third of the edible parts of
food produced for human consumption, amounting to about 1.3 billion tons per
year.^] As the
following table shows, industrialized and developing countries differ
substantially. In the latter, more than 40% of losses occur at the postharvest
and processing stages, while in the former; more than 40% of losses occur at
the retail and consumer levels. The total food waste by consumers in
industrialized countries (222 million tons) is almost equal to the entire food
production in sub-Saharan Africa (230 million tons).

A 2013 report of the British Institution
of Mechanical Engineers(IME) likewise estimated that 30–50% (or 1.2–2 billion
tonnes) of all food produced remains uneaten.