Page 15 - PR 2014 2016 03 Applications of Ionizing Radiations
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Applications of Ionizing Radiations | Progress Report 57
Figure 23.
Polyethylene
film used as an
agricultural stove
Industrial and
is necessary. Additionally, it has some limits
to irradiate food, as in any other process in Environmental Applications
the food industry. Irradiation is effective of Ionizing Radiation
in public health by inactivating harmful
microorganisms and food borne parasites.
Modification and preparation of
Oxidation results in hydroperoxides de - polymeric materials and composites
composing into hydrocarbons, aldehydes,
ketones, alcohol and acids, which interfere Behavior of linear low density polyethylene
with sensory characteristics, as they form films under UV ageing for agricultural applica-
unpleasant flavors and a special flavor that tion Polyethylene is the most important poly-
are commonly known as rancidity, and re- mer used in agricultural applications. Polymers
duce nutritional value by degrading fat and are susceptible to changes in their chemical
fat soluble vitamins. Oxidative deteriora- structures that affect their mechanical prop-
tion of lipids leads to the development of erties under weather condition. In Polyeth-
rancidification, undesirable flavors, polym- ylene, photo-oxidation can occur because of
erization and other reactions resulting in impurities or chromophore groups (catalytic
reduced shelf life, nutritional quality and residue, mineral fillers, some commercial ad-
food safety. The oxidation of fatty acids gives ditives as stabilizers, lubricants, plasticizers,
rise to numerous compounds among them etc.). The critical ageing factors for greenhouse
the formation of 2-ACBs among other com- built with LDPE film are: total solar radiation,
pounds contained in the lipids of irradiated air temperature, relative humidity, mechan-
foods. Many studies report that 2-ACBs are ical stress, agrochemicals, air pollution, and
compounds formed solely by the irradiation combinations of these factors. Exposure of
process and increase linearly according to plastics to UV radiation causes a loss in their
the radiation dose. Studies of genotoxicity mechanical properties and/or change in ap-
and cytotoxicity are being done by the group pearance, including reduced ductility, color
to provide basic information on cell culture changes, yellowing and cracking. Additives
and laboratory animals on this topic which are added to plastics to enhance the durability
should be deepened knowledge and provide of the final product. Today, there are several
data to government bodies for safe control additive systems (light stabilizers) developed
of this process and establish minimal and to work according to resin, final application,
maximum safe limits quantities in the food. type of cultivation, and other characteris-
