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Section 4 Technological Contexts
New chemicals, such as nitrites,
benzoates, and sulfites, are used today
as preservatives. They either inhibit the
growth of bacteria or kill them. These
chemicals can be found on the ingredient
lists of many different foods. For example,
sulfur dioxide preserves fruits used to make
jam, fruit juice, and dried fruits. All these
chemicals can be harmful if used in large
amounts. The FDA limits the amounts of
these chemicals allowed in foods.
Irradiation
Irradiation is the process by which
X-ray radiation is used to kill bacteria in
food. This process kills bacteria without
significantly changing the food. Irradiation
can occur after foods have been pack-
aged, which is a big advantage. If a food
is sealed in plastic and then irradiated, the
food becomes sterile and can be stored
on a shelf without refrigeration for a long
time. The FDA has approved the irradia-
tion of chicken and beef. The use of this
technique can prevent many forms of food
Figure 19-34. Dried fruits are commonly eaten
as snacks and included in breakfast cereals and
bars. (©iStockphoto.com/dkgilbey)
Think Green
Sustainable Agriculture
You have learned about the various aspects of agriculture in this
chapter. Sustainable agriculture takes all those aspects and works
toward developing more environmentally friendly ways of continuing
to use these resources. Sustainable agriculture doesn’t use factory
farming, which takes a more industrial approach, and can pollute
the soil, water, and air with various wastes. Sustainable agriculture
uses natural fertilizers and crop rotation, as well as other measures,
to raise livestock and grow crops responsibly in order to leave little
to no impact on the environment. Local farmers’ markets are an
example of sustainable agriculture.
Figure 19-35. The production of a dry-cured,
Spanish ham called jamón serrano.
(©iStockphoto.com/Miguelito)