The aim of this current work is to analyze the behavior of OSL (Optically
Stimulated Luminescence) signals of irradiated spices with respect to time,
temperature, origin and the type. Throughout the experiments, 3 different type
spices from four different origins were stored at 4° / C and 25° / C for six months after
irradiation.
During experiments, unirradiated red pepper, thyme and cumin samples were analyzed
by using OSL technique in order to determine the background OSL signal values of
samples.
Samples were irradiated 10 kGy by Cobalt 60 gamma source in TAEK (Turkey Atomic
Energy Association).
After irradiation process, OSL signal values of different samples were analyzed
according to the given parameters. In order to determine the effect of temperature
on OSL signal loss, temperature (4° / C- 25° / C) was set as storage temperature. The
analyses were made monthly.
According to the statistical analyses (ANOVA- General Linear Model), origin and type
of samples were detected as significant parameters of design experiment. Time and
temperature effect on OSL signal loss changed with respect to origin and type of
samples.
After six months storage period, OSL signal was lost for most of the origin and
sample type. At the end of sixth month, an ESR analysis was performed to detect the
accuracy of the OSL technique. With respect to the results of these experiments, it
was seen that, due to optical fading, most of the samples was observed as
unirradiated by OSL technique, however ESR analyze the samples as irradiated at the
end of sixth month.
Irradiation had a detrimental effect on the microbiological load of the samples and
resulted 6 log reduction on the microbial population. After irradiation, no colony
formation was observed in total bacteria and yeast- mold count. During six month
period, no injury recovery was observed.
| Identifer | oai:union.ndltd.org:METU/oai:etd.lib.metu.edu.tr:http://etd.lib.metu.edu.tr/upload/12612333/index.pdf |
| Date | 01 September 2010 |
| Creators | Aygun, Sukran Gizem |
| Contributors | Bozoglu, Faruk Tahsin |
| Publisher | METU |
| Source Sets | Middle East Technical Univ. |
| Language | English |
| Detected Language | English |
| Type | M.S. Thesis |
| Format | text/pdf |
| Rights | To liberate the content for public access |
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