• Journal of the Korean Society of Food Science and Nutrition
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• v.35 no.8
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• pp.1064-1069
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• 2006

This study was conducted to sanitize commercial powdery soup by gamma irradiation. Total aerobic bacteria counts were $3.22{\sim}3.77\;log\;CFU/g$ in non-irradiated samples, which decreased with irradiation dose and were not detected in irradiated samples at 3 kGy or more $(<10^2\;CFU/g)$ during accelerated storage $(60^{\circ}C,\;2\;weeks)$. Microbial counts did not significantly increase in all samples during accelerated storage period. Yeasts, molds, and coliform bacteria were not detected in all samples. Irradiated samples showed undesirable changes in flavor, taste, and overall acceptability and acceptance decreased in all samples after 2 weeks at $60^{\circ}C$. These results suggested that gamma irradiation at 3 kGy was effective to ensure the microbiological quality of commercial powdery soup with minimized sensorial changes, but further studies should be investigated to reduce detrimental effects induced by irradiation.

• Food Science of Animal Resources
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• v.29 no.2
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• pp.194-202
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• 2009

This study was conducted to determine the effects of gamma and e-beam irradiation on the quality of minced pork and pork patties. Each sample was irradiated at 5 to 20kGy, and its quality characteristics were then evaluated during storage at 30. The results of the total bacterial populations in the minced-pork and pork patty samples showed that the antimicrobial effect of gamma irradiation was superior to that of e-beam irradiation. The 2-thiobarbituric acid reactive substances (TBARS) value of all the samples significantly increased (p<0.05) as the irradiation dose and storage period increased. In addition, the gamma-irradiated (GI) samples had higher (p<0.05) TBARS values than the e-beam-irradiated (EI) samples. The volatile basic nitrogen contents of the GI samples were lower (p<0.05) than those of the EI samples. The color values, such as the $L^*$(brightness), $a^*$(redness), and $b^*$(yellowness) of the minced pork and pork patties, were increased (p<0.05) by irradiation. The hardness and sensory properties, such as the color, chewiness, taste, and overall acceptability of the pork patties, were decreased when the irradiation dose increased, and the hardness and sensory scores of the GI samples were lower than those of the EI samples.

• Journal of the Korean Society of Food Science and Nutrition
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• v.33 no.2
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• pp.271-277
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• 2004

This study was designed to evaluate the effect of Bu -Zhong-Yi-Qi-Tang extracts, a prescription of traditional oriental medicine, on development of the B cells. In the bone marrow cell cultures, progenitors viability, expressions of particular cell- surface proteins and production of immunoglobulins were investigated in the presence of Bu-Zhong-Yi-Qi-Tang extracts. The administration of Bu-Zhong -Yi-Qi-Tang polysaccharide fraction increased the viable cell numbers of the precursor B cells, and elevated expression levels of CD19/CD40 specific for pre-B cells after 10 days culture were demonstrated by flow cytometry analysis. The production of immunoglobulin M in the presence of polysaccharide fraction increased progressively in the culture supernatant, and preferentially induced class switching to IgG1, IgG2a and IgG3. These results indicated that Bu -Zhong -Yi-Qi -Tang strong1y correlated with the development of precursor B cells in the bone marrow cell culture. Therefore the polysaccharide fraction of Bu-Zhong-Yi -Qi-Tang might be a useful radioprotector, especially since it is a relatively non-toxic natural product. Further studies are needed to better characterize the protective nature of Bu-Zhong-Yi -Qi -Tang extract.

• Food Science and Preservation
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• v.23 no.1
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• pp.139-143
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• 2016

This study investigated the effect of electron beam (EB) treatment on the microbial reduction of dried laver (Porphyra tenera) and identified EB-resistant bacteria from the treated dried laver. After EB treatments of 4 kGy and 7 kGy, the numbers of total bacteria and EB-resistant bacteria were measured using tryptic soy agar and mannitol salt agar, respectively. The morphological and biochemical characteristics of each isolated EB-resistant bacteria were investigated and these bacteria were identified. Compared to the control ($1.5{\pm}0.2){\times}10^6CFU/g$, the total bacterial number was significantly decreased to ($5.4{\pm}0.5){\times}10^4CFU/g$ and ($1.1{\pm}0.6){\times}10^4CFU/g$ after EB treatments of 4 kGy and 7 kGy, respectively. With a higher EB dosage, the number of red colonies was almost same, whereas the number of yellow colonies was significantly decreased to ($3.3{\pm}1.2){\times}10^3CFU/g$ and 0 CFU/g for 4 kGy and 7 kGy, respectively. All red and yellow colonies were gram-positive cocci, catalase-positive, and resistant to 3% and 5% NaCl media. From the 16S rDNA sequence analysis, yellow and red colonies were identified as either Micrococcus flavus or M. luteus, with 99% similarity for the yellow colonies, and Deinococcus proteolyticus and D. piscis, with 99% and 97% similarity for the red colonies, respectively.

• Journal of Food Hygiene and Safety
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• v.1 no.1
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• pp.107-113
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• 1986

It is estimated that the loss of Korean agricultural and fishery products during the storage period is usually more than 20%, and it is difficult to increase agricultural products by a 10% annual rate directly. Therefore, development of food preservation techniques has now become a most important atternative for the indirect increase of such products and for its senitary distribution. Changes eating habits and improved living conditions have accelerated the demand for convenience food production and for this reason it is essential that raw materials at stable, resonable prices and hygienic quality be available the year round. At the end of 1980, the Korean government conceded th economical feasibility of the storage of foods by irradiation and a procedure for preserving food by irradiation on a batch scale was successfully developed by KAERI in 1982. Based on the research results accomplished by the KAERI and on the recommendation on wholesomeness of irradiated food by Joint Committee of FAO/IAEA/WHO in 1980, the approval of wholesomeness of irradiated food was declared by presidential decree in June 1985 and the procedure of permission for individual items is in progress. Korean private firms (Ryung Young Co.) which was technically assisted by KAERI for five years have taken mush interest in the establishment of such facilities in Korea, therefore Ryung Young Co. had proposed for the construction of 500 Kci Co-60 irradiator to the Ministry of Science and Technology in July 1984. The permission of construction has approved by government in May 1985. The commercial irradiator will be constructed as one of the most modernized facilities until May 1987 and that facilities will contribute the propagation of commercial storage of foods and its hygienic quality.

• Journal of the Korean Society of Food Science and Nutrition
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• v.34 no.5
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• pp.729-733
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• 2005

This study was conducted to sanitize fried-frozen cheese ball by gamma irradiation. Total aerobic bacteria and yeasts and molds counts were 4.4 and 2.8 log CFU/g in non-irradiated sample, respectively. Microorganisms were decreased with increase of irradiation dose $(D_{10}=1.25\;kGy)$, and were not detected in samples irradiated at 3 kGy or more $(<10^2\;CFU/g)$. $D_{10}$ value for Escherichia coli (KCTC 1682) was 0.25 kGy. TBA (2-thiobarbituric acid) values were increased as irradiation dose was increased, but there was no significant difference between non-irradiated and irradiated samples at 3 kGy or less (p<0.05). The results of sensory evaluation showed that there was no significant difference between non-irradiated and irradiated samples at 3 kGy or less, the sensory scores were decreased with irradiation at 5 kGy or more (p<0.05). These results indicated that gamma irradiation at 3 kGy was considered to be an effective treatment to ensure the microbiological safety of fried-frozen cheese balls without any sensorial change, even though further studies should be investigated to reduce detrimental effects induced by irradiation.

• Korean Journal of Food Science and Technology
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• v.34 no.4
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• pp.652-660
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• 2002

To develop natural food preservatives for extending the shelf-life of jeotkal (salted and fermented seafood), antimicrobial substances were extracted from 32 types of medicinal herbs and edible plants using 95% ethanol. Among the extracts, Glycyrrhizae radix, Curcumae domestica, Galla rhois, and Resina pini showed relatively high inhibitory effects on the growth of the microorganisms isolated from the deteriorated jeotkal. We selected and tested the extract from Recina pini as a natural jeotkal preservative. This ethanol extract was purified partially by adding equal quantity of water, through which 77% of insoluble materials were removed as impurities. In manufacturing modified jeotkal using squid, sucrose and starch syrup were substituted with sorbitol, $glucono-{\delta}-lactone$ was added instead of vitamin C and lactic acid, and sterilized hot pepper was used instead of natural one. The shelf-life of modified jeotkal was prolonged by 4 days compared with the control jeotkal when stored at $20^{\circ}C$, while that of modified jeotkal containing 1.0% partially purified Recina pini extract was prolonged by 6 days compared to the control. The same tests were conducted for the changran (stomach and intestine of Alaska pollack) jeotkal preservation. The shelf-life of the control jeotkal was 24 days, whereas the modified jeotkal and the Resina pini extract-containing modified jeotkal maintained their qualities without changes in microbial and chemical characteristics for 90 days at $20^{\circ}C$ storage.

• Korean Journal of Food Science and Technology
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• v.40 no.3
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• pp.343-348
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• 2008

The ovomucoid (OM) of egg whites is recognized as a major allergen. Here, the allergenicity of OM in egg whites (EW) treated by chemical, enzymatic, and physiological methods were investigated by competitive inhibitory ELISA using human IgE antibody acquired from egg-allergic patients. Enzymatic hydrolysis, irradiation, and succinic anhydride treatments did not reduce the allergenicity of the OM effectively. Allergenicity was reduced to only 1/20 by deglycosylation with trifluoromethanesulfonic acid (TFMS). Heat treatment of the OM at $121^{\circ}C$ for 10 min reduced allergenicity to 1/100. Furthermore, NaOH (over 3%) treatment reduced allergenicity to 1/10,000, and the combinatory treatment of NaOH (over 0.3%) and heat ($70^{\circ}C$, 15 min) reduced it to less than 1/10,000, which was the most effective method. In this study, which analyzed treated EW using ELISA and patient-derived IgE, the OM allergenicity was nearly the same as its antigenicity according to ELISA using rabbit IgG. However, in the case of the TFMS-treated EW, the antigenicity was much lower than the allergenicity. These results suggest that the allergenicity of OM is slightly different from its antigenicity.

• Journal of Food Hygiene and Safety
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• v.33 no.6
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• pp.438-446
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• 2018

The purpose of this study was to investigate food safety awareness, knowledge, and behavior in college students, to provide basic data for the increase in food safety awareness. Data were collected from 252 college students in Gyeonggi region, using a self-administered questionnaire. In results of concern about food safety, subjects responded 3.48 of 5.00 and have knowledge about food safety education revealing significantly higher awareness and concern than subjects without knowledge about food safety education. Food safety awareness of distributed food was 2.55, considered unsafe. Among reasons in perceiving food as unsafe, 62.3% of subjects expressed distrust about safety relative food production. As for risk factors relative to food safety, subjects responded that the highest risk factor was food additives (2.35), followed by heavy metal (2.38) and endocrine disrupters (2.38). Correlation analysis resulting in risk factors for food had positive correlation with each other, heavy metal revealed highest correlation with pesticide residue (r = 0.674), than with endocrine disrupters (r = 0.672). Also, genetically modified food revealed high correlation with radiation irradiated food. Regression analysis demonstrated that concern about food safety significantly influenced pro-actively engaging in food safety education. Meanwhile, 63.5% of subjects correctly responded to food safety knowledge items. The item 'the heavy metals are contaminated the most, in the roots of vegetables' revealed the lowest correct answer rate (38.1%). In food safety behavior, the item 'always wash hands before handling food and meal's revealed 3.85, and subjects with awareness and concern about food safety education, responded in significantly higher numbers than subject without awareness and concern about food safety. The most neglected concern was relative to frozen food thawed at room temperature. Together, students recognize that distributed foods are unsafe, and students with awareness and concern about food safety education showed higher knowledge compared to without awareness and concern experience about food safety eduction. So, systematic education using accurate and objective data is required to reduce anxiety and raise the level of awareness and concern about food safety.

• Food Science and Preservation
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• v.18 no.1
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• pp.1-6
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• 2011

Kochujang-gulbi, a Korean traditional food, was prepared with kochujang and freeze-dried gulbi slices. Kochujang-gulbi was treated with high hydrostatic pressure (200, 400 and 600 MPa) and gamma-irradiation (7, 10, 20 and 30 KGy) to improve its quality and shelf-life. The pH of high hydrostatic pressure and gamma-irradiation treated kochujang-gulbi samples did not significantly different compared to that of control. However, Hunter L value slightly increased, and Hunter a and b values decreased by high hydrostatic pressure and gamma-irradiation treatment. During storage, the pH and color of high hydrostatic pressure and gamma-irradiation treated kochujang-gulbi samples did not significantly changed. The VBN and TBA level decreased by the increase treatment of high hydrostatic pressure and then slowely increased during storage. The VBN and TBA level of kochujang-gulbi samples treated by the strong gamma ray emission slowely increased during storage. In particular, gamma-irradiation treatment was very effective to sterilize microorganisms when compared to that of high hydrostatic pressure in kochujang-gulbi products. In addition, the high hydrostatic pressure and gamma-irradiation treated kochujang-gulbi samples shown significantly lower total viable cell number than control for the 20 days of storage at room temperature with retort pouch packaging.