• Food Science and Preservation
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• v.15 no.5
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• pp.769-773
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• 2008

Aqueous chlorine dioxide ($ClO_2$) treatment of Samgae chicken was evaluated in terms of microbial safety and quality during refrigerated storage. Samgae chicken samples were treated with 0, 50, or 100 ppm of $ClO_2$ solution, and stored at $4^{\circ}C$ for 10 days. $ClO_2$ treatment significantly decreased the populations of total aerobic bacteria. One-hundred ppm $ClO_2$ treatment reduced the initial populations of total aerobic bacteria by 0.73 log CFU/g. The pH and volatile basic nitrogen values of Samgae chicken increased during storage, with no significant between-treatment difference. Sensory evaluation results showed that the quality of chicken treated with $ClO_2$ prior to refrigerated storage was better than that of the control. These results suggest that $ClO_2$ treatment could be useful in improving the microbial safety and quality of Samgae chicken.

• Food Science and Preservation
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• v.9 no.3
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• pp.321-326
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• 2002

Paeksulkis(Korean rice cake) containing 0-0.5% chitosan were prepared for test the quality of microbiological, mechanical and sensory characteristics. The pH of Paeksulkis was 5.65 without chitosan and that was about 7.0 with 0.05-0.5% level of chitosan. In Hunter's color values of Paeksulkis of control, the lightness(L) was 84.28, redness(a) was -1.56 and yellowness(b) was 7.68. The lightness(L), redness(a) and yellowness(b) were increased with increasing concentration of chitosan in Paeksulkis. In mechanical characteristics of Paeksulkis, cohesiveness and springiness were the highest in control group while strength, hardness, gumminess and brittlenes were higher in chitosan added group than control group. In sensory evaluation of Pasksulkis, control group obtained the highest score in color, texture, after swallowing and overall quality(p<0.05) but chitosan added group obtained higher scores in moisture than control(p<0.05). Total bacterial counts(TBC) of Paeksulgis immediately before storage were 4.2∼9.2$\times$10$^2$CFU/g and those of control increased for 2 weeks, reached at 7.4$\times$10$\^$5/ CFU/g and then decreased about 1 log cycle for 2 weeks during storage at 5$\^{C}$. TBC of Paeksulgis added 0.3∼0.5% of chitosan were 2 log cycles lower than that of control at the end of storage at 5$\^{C}$. TBC of Pasksulgis control increased to 10$\^$8/ CFU/g during storage at 20$\^{C}$ but that of 0.5% chitosan added group was 1 log cycle lower than control at the end of storage. Shelf-life extension of Paeksulkis by chitosan was more effective during storage at 5$\^{C}$ than at 20$\^{C}$.

• Food Science and Preservation
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• v.8 no.4
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• pp.427-433
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• 2001

The purpose of this study was to investigate the effect of chitosan on the shelf-life and quality of Paeksulkis(Korea rice cake). Paeksulgis containing 0-0.5% chitosan were stored at 5$^{\circ}C$ for 4 week and 2$0^{\circ}C$ for 1 week to test the effect of extenting shelf-life of Paeksulgis by chitosan. The pH of Paeksulkis was 5.65 without chitosan and pH of those were about 7.0(6.94-7.01) with 0.05-0.5% level of chitosan. Moisture content of Paekrukis wish or without chitosan was 38-40%. In Hunter’s color values of Paeksulkis of control, the lightness (L) was 84.28, redness(a) was -1.56 and yellowness(b) was 7.68. The lightness (L), redness(a) and yellowness(b) of Paeksulkis were increased by the increasing concentration of chitosan. In mechanical characteristics, cohesiveness concentration of Paeksulkis were the highest in control while obtained the highest score in color, after swallowing and overall quality (p<0.05). The score of flavor and consistency of Paeksulkis with different levels of chitosan wre not significant while the score of moisture in Paeksulkis with 0.05-0.5% level of chitosan was significantly higher than control (p<0.05). The score of flavor and consistency of Paeksulkis with different levels of chitosan were not significant while the score of moisture in Paeksulkis with 0.05-0.5% level of chitosan was significantly higher than control (p<0.05). Total bacterial counts (TBC) of Paeksulgis immediately before storage were 4.2$\times$10$^2$CFU/g in control and those containing 0.3-0.5% of chitosan were 0.5-1.0 log cycle lower than control. TBC of Paelsulgis containing chitosan was lower than increased for 2 weeks, reached at 1.8$\times$10$^{5}$ CFU/g and decreased for 2 weeks, reached at 1.8$\times$10$^4$CFU/g during storage at 5$^{\circ}C$. TBC of Paeksulkis with more than 0.3% of chitosan were 1.9 log cycles lower than that of control during storage at 5$^{\circ}C$. TBC of Paeksulkis with more than 0.3% of chitosan were 1.9 log cycles lower than that of control during storage at 5$^{\circ}C$ for 4 weeks. TBC of Paeksulgis increased to 10$^{8}$ CFU/g in control and 10$^{6}$-10$^{7}$ CFU/g in more than 0.3% chitosan during storage at 20$^{\circ}C$ for 1 week. The shelf-life of Paeksulkis was increased with increasing concentration of chitosan both temperature at 5$^{\circ}C$ and 20$^{\circ}C$.

• Culinary science and hospitality research
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• v.21 no.6
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• pp.218-228
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• 2015

In this study, the physicochemical characteristics of rice sourdough fermented with Omija extract were investigated. Rice sourdough was made with a 3 stage fermentation process. pH & total titratable acidity, numbers of yeast and lactic acid bacteria, and dough expansion rate were measured. In addition, an RVA was employed to study the pasting properties of rice sourdough. There was a significant (p<0.05) change in both the pH of rice sourdough, which decreased from 5.08 to 3.98, and total titratable acidity, which increased from 0.20 to 0.57 (0.1N NaOH mL), as fermentation time increased. The amount of yeast and lactic acid bacteria significantly increased from 6.73 to 7.65 log CFU/g, 6.93 to 7.65 log CFU/g, respectively(p<0.05). The expansion rate of rice sourdough fermented with Omija extract was higher than rice sourdough fermented without Omija extract. The initial pasting temperatures of rice sourdough fermented with Omija extract were decreased from $91.3^{\circ}C$ to 85.6. The final viscosity and setbacks decreased as fermentation time increased. These results suggest that Omija extract has a beneficial effect on increasing the expansion rate of rice sourdough as a substitute for wheat flour.

• Journal of Applied Biological Chemistry
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• v.62 no.4
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• pp.407-415
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• 2019

The biological half-life of pesticides applied on crops is the key indicator for ensuring the safety of agricultural products. The biological half-life is affected by the several factors like growing conditions of the crop, climate, application method, and physicochemical properties of pesticides. In this study, the biological half-life was calculated and the degradation rates of six triazole fungicides sprayed on perilla leaves were evaluated. Moreover, the statistical analysis confirmed the correlation between the biological half-life and physicochemical properties of six triazole pesticides. The recoveries of the six pesticides were between 84.8-104.9%, which satisfied the residual pesticide analysis criteria. The biological half-life of six pesticides sprayed on perilla leaves, calculated using the first-order kinetics model, ranged between 6.4-15.1 days. When the biological half-life and the physicochemical properties were correlated using the principal component analysis: pKa and Log P, the biological half-life was found to be affected by PC1. The correlation coefficient between biological half-life and physicochemical properties (pKa), calculated by Spearman rank-order correlation, was R² = -0.928 (p <0.01). Biological half-life has been shown to correlate with pKa. In conclusion, it can be used as a database for the relationship between biological half-life and physicochemical properties and will contribute to ensure safe supply of agricultural products.

• Journal of Food Hygiene and Safety
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• v.23 no.2
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• pp.137-141
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• 2008

To evaluate safety of commercial skate product, Korean traditional ready-to-eat raw-fish, during from June to August in 2006, microbial and chemical properties such as levels of total plate count, coliform, food-borne pathogens, VBN-value, pH and ammonium concentration in ready-to-eat skate product were evaluated. Total plate counts of ready-to-eat skate product were ranges from 4.8 to 7.5 log CFU/g, and coliform was detected in 1 sample (2.48 log CFU/g) among 18 samples. Staphylococcus aureus, was detected in 2 samples among 18 samples, but Escherichia coli, Salmonella, spp., Vibrio parahaemolyticus, and Listeria monocytogenes were not detected. VBN-values and pH of skate were ranges from 12.6 to 593.9 mg% and from 6.7 to 9.4 depending on strength of fermentation, respectively. Ammonium concentrations of fermented skate were ranges from 4.4 to 14.1 mg/g and 2 samples, pre-fermented skate, were not detected.

• Journal of the Korean Society of Food Science and Nutrition
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• v.42 no.4
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• pp.615-620
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• 2013

To extend the shelf-life of salted Chinese cabbages, electrolyzed water (EW) was used to wash raw Chinese cabbages before the salting process (to control microbial growth), and different storage temperatures evaluated (0, 4, and $10^{\circ}C$). A tap water washing group (TW) was used for comparison. The initial total bacterial population was 5.36 log CFU/g in the TW treatment and 3.50 log CFU/g in the EW treatment. The EW treatment decreased bacterial numbers by approximately 2 log CFU/g compared to the TW treatment and kept this initial population number for 32 days at $0^{\circ}C$. The salinity had no difference during storage. In general, several factors (pH, reducing sugars, hardness, and transmittance) decreased over time, and decreased slowly with EW treatment and $0^{\circ}C$ storage. Overall, the salted Chinese cabbages with EW treatment showed lower bacterial populations compared to TW treatment, and when stored at $0^{\circ}C$, delayed decreases in quality.

• Journal of Soil and Groundwater Environment
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• v.18 no.3
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• pp.82-92
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• 2013

This study has investigated naturally occurring radioactive materials (N.O.R.M; $^{238}U$, $^{222}Rn$) for 353 drinking groundwater wells in metamorphic rock areas in Korea. Uranium concentrations ranged from N.D (not detected) to 563.56 ${\mu}g/L$ (median value, 0.68 ${\mu}g/L$) and radon concentrations ranged from 108 to 11,612 pCi/L (median value, 1,400 pCi/L). Uranium and radon concentrations in the groundwater generally are similar to USA with similar geological setting. Uranium concentrations in 9 wells (2.6%) exceeded 30 ${\mu}g/L$, which is the maximum contaminant level (MCL) by the US environmental protection agency (EPA), radon concentrations in 46 wells (13%) exceeded 4,000 pCi/L, which is the Alternative MCL (AMCL) by the US.EPA. The log-log correlation coefficient between uranium and radon was 0.32. The correlation coefficient between uranium and pH was 0.12 and the correlation coefficient between radon and temperature was -0.01. The correlation coefficient between uranium and $HCO_3$ was 0.09 and the correlation coefficient between uranium and Ca was 0.11. The median value of uranium was high Chung-Buk (1.78 ${\mu}g/L$), Gyeong-Buk (1.37 ${\mu}g/L$), In-Cheon (1.06 ${\mu}g/L$) for each province. On the other hand, the median value of radon was high In-Cheon (2,962 pCi/L), Chung-Buk (2,339 pCi/L), Jeon-Buk (2,165 pCi/L) for each province. Jeon-Buk for log-log correlation coefficient is the highest (0.63) among provinces.

• Food Science and Preservation
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• v.17 no.4
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• pp.457-465
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• 2010

We sought to develop lotus (Nelumbo nucifera) root Jeonggwa as a health food. Jeonggwa was mixed with 0-8% (w/w) Omija water extract and stored at $25^{\circ}C$ for 12 weeks. Quality characteristics during storage were investigated. The pH of Jeonggwa fell, and the acidity level rose, as increasing amounts of Omija water extract were added. The moisture content of Jeonggwa rose from 7-8% to 14-17% within 2 weeks of storage at $25^{\circ}C$, and was maintained at that level to the end of storage. Total viable bacterial cells in Jeonggwa were initially 2.4~3.2 log CFU/g, and increased in number during storage, but never exceeded 4 log CFU/g. The shelf life of Jeonggwa was extended when Omija extract was added. The lightness (L), redness (a). and yellowness (b) of Jeonggwa during storage at $25^{\circ}C$ were highest in control samples and the values fell with increasing Omija extract concentration (p<0.001). Mechanical evaluation Jeonggwa showed that various tested parameters fell during storage at $25^{\circ}C$. The hardness and strength of Jeonggwa were significantly reduced as the Omija extract concentration rose (p<0.05). In sensory evaluation tests, the acceptability of Jeonggwa was optimal when 2~4% (w/w) Omija extract was added.

• Korean journal of food and cookery science
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• v.30 no.5
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• pp.642-649
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• 2014

We investigated the antioxidant and physicochemical qualities as well as the sensory characteristics, and microbial safety of sunsik containing varied amounts of AF-343, which can help add moisture to the skin and relieve the symptoms of atopic dermatitis. Samples did not show significant differences in pH measurements, but the pH had a tendency to increase with tendencies as increased amounts of AF-343. The total phenolic compound contents and DPPH radical scavenging activity, indicators of biologically active ingredients such as antioxidant, anticancer and antibacterial activity, significantly increased as the amounts of AF-343 increased (p<0.05). In an acceptance test, the samples did not show significant differences, however samples with the 750 mg AF-343 received the highest scores out of all the samples in overall acceptance. All samples were confirmed as microbially safe according to the food code applied to food manufacturers. Aerobic plate counts of the control group were 1.60 log CFU/g, while those of samples with 750 mg AF-343 were 1.70 log CFU/g. E. coli. Pathogenic microorganisms tests were either negative or not detected in all samples.