Detection of Gamma irradiated spices with OSL method and its reliability

Download

index.pdf

Date

2010

Author

Aygün, Şükran Gizem

Metadata

Show full item record

Item Usage Stats

150
views

87
downloads

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.

Subject Keywords

Food Processing and Manufacture.

URI

http://etd.lib.metu.edu.tr/upload/12612333/index.pdf
https://hdl.handle.net/11511/19842

Collections

Graduate School of Natural and Applied Sciences, Thesis

Suggestions

OpenMETU
Core

Modeling of tempering of frozen potato puree by microwave, infrared assisted microwave and ohmic heating methods Seyhun, Nadide; Şümnü, Servet Gülüm; Department of Food Engineering (2008) The main purpose of this thesis is to develop a model that can predict the temperature profile inside a frozen food sample during microwave tempering and infrared assisted microwave tempering processes. Another goal of the study is to compare the tempering time of frozen foods by using microwave, infrared assisted microwave, and ohmic heating methods. Frozen potato puree was used as the food sample for all studies. Three different microwave power levels (30%, 40%, and 50%) were used for microwave tempering ...
Supercritical carbon dioxide extraction of apricot kernel oil Özkal, Sami Gökhan; Yener, Meryem Esra; Department of Food Engineering (2004) The purpose of this research was to determine the solubility of apricot (Prunus armeniaca L.) oil in supercritical carbon dioxide (SC-CO2), effects of parameters (particle size, solvent flow rate, pressure, temperature and co-solvent (ethanol) concentration) on extraction yield and to investigate the possibility of fractionation. Solubility, increased with pressure and increased with temperature above the crossover pressure, which was found between 200 and 300 bar, and decreased with temperature below the c...
Recovery of strawberry aroma compounds by pervaporation İşçi, Aslı; Şahin, Serpil; Department of Food Engineering (2004) Pervaporation is a selective membrane technique in which a liquid feed mixture is separated by means of partial vaporization through a non-porous perm-selective membrane. This method can be used for the recovery of heat sensitive aroma compounds to avoid them from thermal damage in beverage industries. The main objective of this study was to determine the effects of feed temperature (30, 40, 50°C), composition (different model solutions, strawberry essence), concentration (50, 100, 150 ppm) and permeate pre...
Optimization of microwave-halogen lamp baking of bread Demirekler, Pınar; Şümnü, Servet Gülüm; Department of Food Engineering (2004) The main objective of this study was to optimize the processing conditions of breads baked in halogen lamp-microwave combination oven by using response surface methodology. It was also aimed to construct neural network models for the prediction of quality parameters of bread as a function of processing conditions. Different baking time and power combinations were used in order to find the optimum baking conditions of bread in halogen lamp-microwave combination oven. The independent variables were the baking...
Modification of calcium carbonate surfaces in natural gas plasma for their use in polypropylene composite systems Öztürk, Serhat; Akovalı, Güneri; Department of Polymer Science and Technology (2006) In this study calcium carbonate (CaCO3) particles are surface modified by using plasma polymerized natural gas and effects of surface modification of CaCO3 filler on mechanical properties of CaCO3-PP composites are investigated. Different combination of plasma factors; RF power, natural gas flow rate, and plasma discharge durations, are investigated. Mechanical properties such as tensile strength and Young’s Modulus are measured by tensile testing machine. Storage modulus and loss modulus measurements are d...

Citation Formats

Ş. G. Aygün, “Detection of Gamma irradiated spices with OSL method and its reliability,” M.S. - Master of Science, Middle East Technical University, 2010.