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Nutrition, industry and food
processing
Since the Industrial Revolution some two hundred years ago, the food
processing industry has invented many technologies that both help
keep foods fresh longer and alter the fresh state of food as they
appear in nature. Cooling is the primary technology that can help
maintain freshness, whereas many more technologies have been
invented to allow foods to last longer without becoming spoiled.
These latter technologies include pasteurisation, autoclavation,
drying, salting, and separation of various components, and all
appear to alter the original nutritional contents of food.
Pasteurisation and autoclavation (heating techniques) have no doubt
improved the safety of many common foods, preventing epidemics of
bacterial infection. But some of the (new) food processing
technologies undoubtedly have downfalls as well.
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Modern separation techniques such as milling, centrifugation, and
pressing have enabled upconcentration of particular components of
food, yielding flour, oils, juices and so on, and even separate
fatty acids, amino acids, vitamins, and minerals. Inevitably, such
large scale upconcentration changes the nutritional content of food,
saving certain nutrients while removing others. Heating techniques
may also reduce food's content of many heat-labile nutrients such as
certain vitamins and phytochemicals, and possibly other
yet to be discovered substances.] Because of reduced nutritional
value, processed foods are often 'enriched' or 'fortified' with some
of the most critical nutrients (usually certain vitamins) that were
lost during processing. Nonetheless, processed foods tend to have an
inferior nutritional profile than do whole, fresh foods, regarding
content of both sugar and high GI starches, potassium/sodium,
vitamins, fibre, and of intact, unoxidized (essential) fatty acids.
In addition, processed foods often contain potentially harmful
substances such as oxidized fats and trans fatty acids.
A dramatic example of the effect of food processing on a
population's health is the history of epidemics of beri-beri in
people subsisting on polished rice. Removing the outer layer of rice
by polishing it removes with it the essential vitamin thiamine,
causing beri-beri. Another example is the development of scurvy
among infants in the late 1800's in the United States. It turned out
that the vast majority of sufferers were being fed milk that had
been heat-treated (as suggested by Pasteur) to control bacterial
disease. Pasteurisation was effective against bacteria, but it
destroyed the vitamin C.
As mentioned, lifestyle- and obesity-related diseases are becoming
increasingly prevalent all around the world. There is little doubt
that the increasingly widespread application of some modern food
processing technologies has contributed to this development. The
food processing industry is a major part of modern economy, and as
such it is influential in political decisions (e.g. nutritional
recommendations, agricultural subsidising). In any known
profit-driven economy, health considerations are hardly a priority;
effective production of cheap foods with a long shelf-life is more
the trend. In general, whole, fresh foods have a relatively short
shelf-life and are less profitable to produce and sell than are more
processed foods. Thus the consumer is left with the choice between
more expensive but nutritionally superior whole, fresh foods, and
cheap, usually nutritionally inferior processed foods. Because
processed foods are often cheaper, more convenient (in both
purchasing, storage, and preparation), and more available, the
consumption of nutritionally inferior foods has been increasing
throughout the world along with many nutrition-related health
complications.
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