Application of epr spectroscopy in preservation of foodstuff with ionizing radiation Part 2. Testing of prescribed dose in foodstuff of animal origin preserved with ionising radiation

Primjena ionizacijskog zračenja u konzerviranju namirnica na svjetskom tržištu, zakonska regulativa vezana uz upotrebu tehnologije zračenja i zahtjev potrošača za jasnom deklaracijom ozračenih namirnica naglasila je potrebu razvoja analitičkih metoda za detekciju namirnica konzerviranih na takav način. Jedna od najpreciznijih metoda za identifikaciju ozračenih namirnica je metoda elektronske paramagnetske rezonancije (EPR). EPR spektroskopija je fizikalna metoda koja promatra nesparene elektrone, posebno slobodne radikale uzrokovane primjenom zračenja. Može se upotrijebiti kao identifikacijski test ako su radikali stabilni tijekom komercijalnog roka upotrebe ozračene namirnice, čije su komponente u čvrstom i suhom stanju, gdje je reaktivnost radikala međusobno i s vodom mala. Primjenjuje se na kostima u mesu i ribi, voću i povrću, te proizvodima takvih namirnica (čaj, začini i sl.), te namirnicama iz mora itd. U ovom radu opisana je primjena EPR spektroskopije u provjeri ispravnosti doze u raznim namirnicama animalnog porijekla konzerviranih ionizacijskim zračenjem.Application of ionising radiation in the preservation of foodstuffs on the world food market, irradiation treatment regulations and demands of consumers for clear declaration of irradiated foodstuffs have emphasised the need for the development of analytical methods for the detection of foodstuffs preserved by ionising radiation. One of the most accurate methods for the identification of irradiated foodstuffs is EPR spectroscopy. EPR spectroscopy is a physical method for detecting unpaired electrons, especially free radicals induced by ionising radiation. EPR can be used as identification test if the radicals are stable over the maximum commercial shelf life of irradiated food with solid and dry components, and where the rigid structure of the matrix inhibits radicals reacting with each other or with food components present in the its wet portion. EPR can be applied to meat and fish bones, fruit and vegetables and the relative products (tea, seasonings, etc.), seafood, etc. This paper describes the use of EPR spectroscopy for assessing the dose level in various foodstuffs of animal origin preserved with ionising radiation

Application of EPR spectroscopy in preservation of foodstuff with ionizing radiation 1. part - accurate detection of irradiation dose by EPR/alanine dosimetry

Paramagnetski centri u L-alaninu ozračenom - zračenjem pokazuju izuzetnu stabilnost u vremenu, a njihova koncentracija proporcionalna je dozi ionizacijskog zračenja za veliki raspon doza (0.5-105 Gy). Ove karakteristike čine osnovu na kojoj se zasniva dozimetrija uz pomoć elektronske paramagnetske rezonancije (EPR/Alaninska dozimetrija). U ovom radu dan je osvrt na primjenu EPR/Alaninske dozimetrije.Stability of paramagnetic centers in -irradiated L-alanine at room temperature and its linear dependence of concentration in the wide range of irradiation dose (0.5-105 Gy) are the most important properties of EPR/alanine dosimeter. In this paper, a review is presented about the use of EPR/alanine dosimetry

Identification of the norway lobster (Nephrops novergicus) preserved with ionising radiation and testing of prescribed dose with electron paramagnetic resonance spectroscopy

Primjena ionizacijskog zračenja u konzerviranju namirnica na svjetskom tržištu, zakonska regulativa vezana uz upotrebu tehnologije zračenja i zahtjev potrošača za jasnom deklaracijom ozračenih namirnica naglasila je potrebu razvoja analitičkih metoda za detekciju namirnica konzerviranih na takav način. Jedna od najpreciznijih metoda za identifikaciju ozračenih namirnica je metoda elektronske paramagnetske rezonancije (EPR). EPR spektroskopija je fizikalna metoda koja promatra nesparene elektrone, posebno slobodne radikale uzrokovane primjenom ionizacijskog zračenja. U ovom radu ta je metoda upotrijebljena kao identifikacijski test za radikale stvorene pri konzerviranju ionizacijskim zračenjem kod škampa i pokazana je primjena EPR spektroskopije za provjeru ispravnosti doze zračenja.Application of ionising radiation in the preservation of foodstuffs on the world food market, irradiation treatment regulations and demands of consumers for clear declaration of irradiated foodstuffs have emphasis the need for the development of analytical methods for the detection of foodstuffs preserved by ionising radiation. One of the most accurate methods for the identification of irradiated foodstuffs is EPR spectroscopy. EPR spectroscopy is a physical method for detecting unpaired electrons, especially free radicals induced by ionising radiation. This paper describes the use of EPR spectroscopy as identificationtest for the radicals induced in Norway lobster during the preservation by ionising radiation and the application of EPR spectroscopy in testing of prescribed dose

Impact of heat-assisted HVED plasma treatment on quality of apple juice

High voltage electrical discharge (HVED) plasma processing receives more and more attention due to its potential to assure microbial safety and retain quality of treated products. The influence of combined thermal and high voltage electrical discharge plasma treatment on apple juice quality was investigated. Apple juice samples were treated under defined plasma treatment parameters of time (3, 6 and 9 min), frequency (60, 90 and 120 Hz) and temperature (30, 40 and 50 oC) in hybrid plasma reactor. Prior to treatment, juice samples were inoculated with Saccharomyces cerevisiae ATCC 204508 to investigate inactivation possibilities of plasma treatment on yeasts as common juice microorganisms. Quality parameters (pH, electrical conductivity, phenolic content and antioxidant activity) of treated and untreated apple juice were investigated and compared. Results have shown effectiveness of HVED plasma treatment in yeast inactivation up to 6.6 log10 in 9 min of treatment at 120 Hz and temperature of 40 oC. In treated samples there were no significant changes in phenolic content

Editorial: Developing novel materials and new techniques of biological and physical retrospective dosimetry for affected individuals in radiological and nuclear emergencies

Retrospective dosimetry estimates radiation doses received by an individual in the past using physical and biological methods. Because of the increasing threat of radiological accidents or terrorist attacks involving radioactive material, the development of this area of research has become extremely important (1, 2). This Research Topic, entitled “Developing Novel Materials and New Techniques of Biological and Physical Retrospective Dosimetry for Affected Individuals in Radiological and Nuclear Emergencies,” provided an opportunity to receive new relevant contributions from various experts who provided new insights and perspectives in the field of retrospective dosimetry. The aim was to connect more scientific fields, researchers and infrastructures from this interdisciplinary research area and to collect studies relevant to human health. The main objective is to improve complementary physical and biological measurement techniques with lower detection limits of received radiation doses, to characterize different appropriate dosimeters, to develop and validate individual dose estimation models, and to propose standardized dosimetry protocols required in the most likely scenarios. It also aims to estimate more accurately radiation dose received by individuals involved in a nuclear accident or radiological emergency using materials on or near the victim and the victim's blood in a relatively short period of time to allow appropriate medical treatment and therapy to increase survival rates

Impact of disorder on formation of free radicals by gamma-irradiation: Multi-frequency EPR studies of trehalose polymorphs

Electron paramagnetic resonance (EPR) studies of the radiation-induced radicals in two anhydrous trehalose polymorphs, beta- crystalline (TREc) and glassy (TREg), were conducted with the aim to resolve whether different types of free radicals are induced in a differently disordered environment. A multifrequency approach (9.5 GHz, 94 GHz, and 244 GHz) was applied to improve the resolution of the complex EPR spectra. In addition, the thermal stability of the EPR spectra and the respective decay kinetics were analyzed in a series of thermal annealing studies in the temperature interval from 333 K to 363 K. It was found that in the crystalline matrix the transformation process of the induced radicals is more complex than in the glassy host matrix. Qualitative decomposition of the experimental spectra, assuming four contributing species, reproduced characteristic EPR spectral features in both matrices. These were interpreted as carbon-centered radicals while the possibility of the formation of alkoxy radicals due to the abstraction of a hydrogen atom could be ruled out. Only in one case, the tentative assignment of the EPR spectral components revealed the formation of the same radical species in both TREc and TREg. Furthermore, by thermal annealing TREg lost one of the radical species, whereas in TREc all 4 radical species pertained irrespective of the treatment. The results presented here, therefore, provide experimental evidence that the extent of disorder present in the material strongly affects the type and stability of radicals induced by ionizing radiation

OSL study of ion-substituted hydroxyapatites

Hydroxyapatite (HA, Ca10(PO4)6(OH)2) is a calcium orthophosphate which due to its similarity to mineral part of hard tissue is best known as biomaterial hard tissue regeneration [1]. However, HA has also been among the most studied dosimetric materials in the high dose and retrospective dosimetry, by the EPR (electron paramagnetic resonance) spectroscopy. As HA substituted with different ions is the one occurring in biological systems, ion-substituted HA are increasingly attracting attention as hard tissue biomaterials [2, 3]. But they could as well be used as OSL (optically stimulated luminescence) dosimeters [4]. To test this hypothesis, in this study influence of Mg and Si substitutions on the OSL response of irradiated HA was determined. Mg and Si substituted HA were synthetized by hydrothermal method. Obtained ion-substituted HAs were characterised by powder X-ray diffraction and scanning electron microscopy. EPR spectroscopy were used to follow and control the changes in relation with substituted ions and correlated with pure HA. Obtained results indicate that Mg and Si ion substituted HA can be potential dose indicator material using OSL technique. However, more detailed study of the influence of the ion substitute concentration and type is needed to confirm their applicability as OSL dosimeters.VIII International Conference on Radiation in Various Fields of Research : RAD 2020 : book of abstracts; Virtual Conferenc