• Korean Journal of Food Science and Technology
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• v.32 no.5
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• pp.1128-1134
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• 2000

This study was carried out to evaluate quality properties of gamma-irradiated Kwamegi prepared from Cololabis seira semi-dried by cold sea wind. Edible portion of Kwamegi was prepared from whole body, vacuum-packaged, gamma-irradiated in the doses of 3 or 5 kGy, and stored at $5^{\circ}C$ for 60 days. Volatile basic nitrogen and trimethylamine contents were not different by gamma irradiation. During storage increase of those two compounds were inhibited depending upon the dose. Thiobarbituric acid values did not differ in all samples, regardless of irradiation and storage. The amount of total volatile compounds of Kwamegi decreased by irradiation. Rheological properties were not affected by irradiation and were maintained up to 60 day when the Kwamegi was irradiated at 5 kGy dose, but those of control was softened. Sensory evaluation had no differences in all samples immediately after irradiation. Sensory quality of Kwamegi irradiated were organoleptically adequate, however that of control was deteriorated. In conclusion, these results indicate that gamma irradiation technique can be used to maintain the quality of Kwamegi.

• Korean Journal of Food Science and Technology
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• v.31 no.3
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• pp.665-671
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• 1999

Post mortem bovine muscle. semitendinosus was used to investigate the effects of gamma irradiation on physicochemical properties. The muscle was cut into pieces of 2 cm in thickness and packaged with 2 different methods; vacuum-packaged and air-packaged. The packaged samples were irradiated at designated doses of 0, 1, 3 and 5 kGy by Cobalt-60 irradiator. Muscle protein solubility, purge loss, composition and contents of free amino acids, and shear force were observed during storage at $4^{\circ}C$. We found no significant differences in the purge loss and the contents of free amino acids. Muscle protein solubility slightly increased depending upon the increase of the dose. The decrease of shear force by gamma irradiation was observed. Therefore, it is considered that meat quality can be improved by gamma irradiation.

• Korean Journal of Food Science and Technology
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• v.18 no.4
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• pp.294-300
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• 1986

Ethylene oxide (E.O) fumigation and gamma irradiation were applied to comparative researches on the sterilizing effect and physicochemical quality of sound red and black peppers. The microorganisms contaminated in the sample, including total bacteria, aerobic spores, acid tolerant bacteria, fungi, osmophilic molds and coliforms were sterilized with irradiation doses of 7 10 kGy, while E.O fumigation in a commonly used condition proved insufficient for the destruction of them. Both treatments affected more or less chemical components of the sample, such as pungent principle, pigment, essential oils and volatile flavors, but the gamma irradiation at the doses for radurization and radicidation was shown to be safer than E.O fumigation.

• Korean Journal of Food Science and Technology
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• v.29 no.4
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• pp.764-770
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• 1997

For the purpose of improving hygienic quality of dried-spirullina and dried-sea tangle powders as raw materials of health food, the comparative effects of ozone treatment and gamma irradiation on the microbial and physicochemical properties were investigated. Gamma irradiation at 7.5 kGy resulted in sterilization of total aerobic bacteria, coliforms and molds below detective levels $(<10^{1}\;CFU/g\;sample)$, while ozone treatment for 8 hr up to 18 ppm could not sufficiently eliminate the microorganisms of the samples. Physicochemical properties including compositions of fatty acid and amino acid, minerals, pH and natural pigments were not changed by gamma irradaition up to 10 kGy, whereas, ozone treatment caused changes in pH, TBA value, natural pigments and fatty acid compositions. Especially, ozone treatment markedly decreased unsaturated fatty acid of the samples.

• Nuclear Engineering and Technology
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• v.41 no.6
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• pp.813-820
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• 2009

A rapid pneumatic transfer system (PTS) for an instrumental neutron activation analysis (INAA) is developed as an automatic irradiation facility involving the measurement of a short half-life nuclide and a delayed neutron counting system. Three new PTS designs with improved functions were constructed at the HANARO research reactor in 2006. The new system is composed of a manual system and an automatic system for both an INAA and a delayed neutron activation analysis (DNAA). The design and basic conception of a modified PTS are described, and the functions of system operation and control, radiation protection and emissions of radioactive gas are improved. In addition, a form of capsule transportation of these systems is tested. The experimental results pertaining to the irradiation characteristics with variation of the neutron flux and the temperature of the irradiation position with the irradiation time are presented, as is an analysis of the reference material for analytical quality control and uncertainty assessments.

• YAKHAK HOEJI
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• v.50 no.6
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• pp.415-420
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• 2006

The purpose of this study was to develop the best methods to sterilize herbal medicines which is frequently used and known to have high susceptibility to microbial contamination. We used dry heat, gamma irradiation and alcohol gas treatment for sterilization, and evaluated these methods in terms of the followings; i) the efficacy of sterilization, and ii) the chemical alteration of index constituents of herbal medicines. Treatment with dry heat effectively eliminated the contaminated microorganisms, and did not significantly alter the content of berberine chloride, paeoniflorin and amygdalin in Phellodendron Bark, Peony Root and Apricot Kernel, respectively: However it seriously changed the color and morphology which are essential criteria to estimate a measure of quality of herbal medicines. Treatment with gamma irradiation showed a strong sterilizing effect, and no alteration of the content of index constituents, color and morphology: Alcohol gas treatment resulted in similar effects as those in gamma irradiation. Collectively; these results suggest that treatment with gamma irradiation or alcohol gas may be useful methods for sterilizing herbal medicines without a decrease in their microbial quality.

• Korean Journal of Food Science and Technology
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• v.26 no.2
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• pp.167-171
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• 1994

With a view to improving microbiological quality of spinach powder which is currently used for convenience food production, comparative efficacy of ethylene oxide(EO) fumigation and gamma irradiation was investigated by determining microbial populations and physicochemical quality for treated samples. Spinach powder was contaminated with various microorganisms ranging from $10^{2}/g\;to\;10^{4}/g$, which composed of thermophiles, acid tolerant bacteria, fungi, coliforms, etc. Microorganisms contaminated were destroyed up to undetected levels by gamma irradiation at below 7 kGy. showing the radiosensitivity $D_{10}$ 2.93 kGy on total aerobic bacteria. Ethylene oxide fumigation, however. was found unsatisfactory for physicochemical quality as well as microbial decontamination of the sample. It has been generally observed that influence of optimum-dose range of irradiation on the physicochemical qualities was insignificant, which was proved in the organoleptic evaluations on the stored sample.

• Korean Journal of Food Science and Technology
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• v.28 no.3
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• pp.482-489
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• 1996

Dried-red pepper, whole and powdered types, was subjected to a storage-study by investigation the effects of packaging methods (polycloth & polyethylene/polycloth, whole dried-red pepper; nylon/polyethylene-lam-inated film, red pepper powder), temperature (ambient, $5{\sim}10^{\circ}C$) and gamma irradiation doses (0-10 kGy). After 6 months storage in polyclith sack at ambient temperature, all whole dried-red pepper showed quality deterioration, such as weight change, insect infestation, discoloration and chemical changes, After 2 years storage in combined packaging with polyethylene/polycloth sack of 5-7.5 kGy irradiated whole dried-red pepper at ambient temperature, however, quality deterioration was not observed. Gamma-irradiated red pepper powder (7.5-10kGy) showed a good quality in hygienic, physicochemical and organoleptic evaluation after 2 years of storage at ambient temperature.

• Food Science of Animal Resources
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• v.28 no.3
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• pp.289-294
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• 2008

The influence of gamma irradiation with low doses (0.5, 1.0, and 1.5 kGy) on the meat quality of chicken breast was determined for 6 days of storage at $4^{\circ}C$. The pH of irradiated chicken was lower than that of the control at day 1 (p<0.05), while no difference was found among irradiation at different doses. Drip loss was higher in irradiated chicken with doses of 0.5 and 1.0 kGy compared to the control at day 1 and day 3 (p<0.05). Lightness (L) at day 1 and day 6 was increased due to irradiation (p<0.05). Redness (a) increased with irradiation doses of 1.0 and 1.5 kGy at day 1 and day 3 (p<0.05). However, no significant differences were found in yellowness (b). The number of aerobic plate count of irradiated chicken during storage was significantly lower than the control (p<0.05). E. coli and coliforms were not detected after irradiation at any dose. Also, irradiation doses of 1.0 and 1.5 kGy significantly reduced volatile basic nitrogen (VBN) and 2-thiobarbituric acid reactive substances (TBARS) values compared to the control during storage (p<0.05). These results suggest that low dose gamma irradiation can be useful to extend the shelf life of chicken breast during cold storage.

• Horticultural Science & Technology
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• v.32 no.4
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• pp.507-516
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• 2014

The present study was conducted to determine the effect of electron beam irradiation on control of Botrytis cinerea and postharvest quality of cut roses. Electron beam doses of 0.1, 0.2, 0.4, 0.6, 0.8, 1, 2, 10, and 20 kGy were applied with a 10-MeV linear electron beam accelerator (EB Tech, Korea). Electron beams inhibited spore germination and mycelial growth of B. cinerea with increasing irradiation doses. Conidia of B. cinerea were more tolerant to irradiation than were mycelia: the effective irradiation doses for 50% inhibition ($ED_{50}$) of spore germination and mycelial growth were 2.02 kGy and 0.89 kGy, respectively. In addition, electron beam irradiation was more effective in reducing mycelial growth of B. cinerea at $10^{\circ}C$ than at $20^{\circ}C$. Analysis of in vivo antifungal activity revealed that elevated irradiation doses exhibited increased control efficacy for tomato gray mold. Flower longevity and fresh weight of cut roses decreased when the irradiation dose was increased. In addition, flower bud opening tended to be inhibited in a dose-dependent manner. Although 'Decoration', 'Il se Bronze', 'Queen Bee', and 'Revue' roses tolerated and maintained overall postharvest quality up to 0.4 kGy, 'Vivian' did not, demonstrating that the irradiation sensitivity of cut roses varies according to cultivar.