• Korean Journal of Food Science and Technology
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• v.39 no.4
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• pp.432-437
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• 2007

In this study, we examined the conditions for an auto-aging system placed within a kimchi refrigerator for optimal fermentation, and to prolong the storage time of kimchi. Various characteristics of kimchi fermented at different temperatures ($5-23^{\circ}C$) were compared. We observed that the higher the fermentation temperature, the less desirable the overall acceptability of the product. To establish the time point in which to convert the fermentation mode to the storage mode, kimchi was stored at $-1^{\circ}C$ for 1 week once it reached the designated acidity (0.4, 0.6, and 0.8%). The results indicated that the lower the kimchi acidity, the higher the sensory score. The storage temperature of $-1^{\circ}C$ was not low enough to retard microorganism growth completely; however, the kimchi stored at $-2{\pm}0.5^{\circ}C$ became frozen. Accordingly, $15^{\circ}C$ and $-2{\pm}0.5^{\circ}C$ are suggested as the fermentation and storage temperatures for the kimchi refrigerator, respectively. A kimchi acidity of 0.4% can be used as an index for the time point to convert fermentation to storage. Subsequently, the time required for the fermentation course can be calculated based on this.

• Journal of Life Science
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• v.17 no.4 s.84
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• pp.498-502
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• 2007

A total of 5 female elk deer($220kg{\pm}10kg$) were included in a study on the changes in physico-chemical properties of deer meat during storage at $-4^{\circ}C\;and\;-2^{\circ}C$. The deers were exposed to normal pre-slaughter handling and put under anesthesia before slaughtered. The loin and leg cuts were deboned from the carcass after 24hrs slaughter. The samples weighing approximately 300g were packaged using wrap packaging and stored for 1, 2, 3, 4, 5 and 6 months at $-30^{\circ}C\;and\;-60^{\circ}C$. During the freezing period, the changes of moisture maintenance was slower for the meats kept at $-60^{\circ}C$ than that at $-30^{\circ}C$. The meat softness represented higher value after freezing, and it tended to be decreased with the passage of storage time. Comparing the values between freezing temperature, the value at $-30^{\circ}C$ was higher than at $-60^{\circ}C$. All meats frozen at $-30^{\circ}C\;and\;-60^{\circ}C$ were edible after storage for 6 months. Loin was inedible, and leg was edible after freezing storage for 6 months. The pH values of the meats were increased during freezing period, even though pH value of the meats stored for 6 months was less than 5.70. Luminosity of loin was significantly increased with the passage of storage time, although loin stored at $-60^{\circ}C$ was darker, and leg stored at $-30^{\circ}C$ was darker. The index of red color was rapidly decreased for loin stored at $-30^{\circ}C$, and for leg stored at $-60^{\circ}C$, respectively. There were no changes in the index of yellow color for loin stored at $-60^{\circ}C$, and the index for leg was increased with regardless of the freezing storage temperature after 6 months.

• Journal of Life Science
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• v.17 no.4 s.84
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• pp.540-545
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• 2007

The purpose of this research is to study the effects of feeding dietary citrus byproducts TMR (total mixed ration) on physicochemical properties and sensory characteristics of Korean native beef loin (KNBL). The samples for experiment consist of the KNBL not fed with citrus byproducts (TMR-0) and the KNBL fed with citrus byproducts during fattening period (TMR-1). The control (TMR-0) KNBL was fed by general practical feeding (roughages and concentrates were fed separately), while the TMR-1 KNBL was fed by the same as TMR-0 until 17 months yearling but was fed by citrus byproducts feeding for 10 months after that. The $L^*(lightness),\;a^*(redness)\;and\;b^*(yellowness)$ value were not significantly different between TMR-0 and TMR-1. The pH of TMR-1 was lower than that of TMR-0 (p<0.05), the VBN content, TBARS value and EDA were not significantly different between TMR-0 and TMR-1. The water holding capacity, frozen loss and cooking loss were not significantly different between TMR-0 and TMR-1, but thawing loss of TMR-0 was higher than that of TMR-1 (p<0.05). The hardness of TMR-0 was higher than that of TMR-1, and the springiness of TMR-1 was higher than that of TMR-0 (p<0.05), but the cohesiveness, gumminess, chewiness and shear force were not significantly different between TMR-0 and TMR-1. The pH and VBN content during storage were not significantly different between TMR-0 and TMR-1, but the TBARS value of TMR-1 stored during 4 weeks was lower than that of TMR-0 (p<0.05). In case of sensory score, the color and aroma of raw meat, and the taste, juiciness and palatability of cooked meat were not significantly different between TMR-0 and TMR-1. But the flavor and tenderness of TMR-1 were superior than those of TMR-0 (p<0.05)

• Journal of Embryo Transfer
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• v.20 no.3
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• pp.317-322
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• 2005

This study was conducted to improve the efficiency of embryo recovery and to establish the protocols of superovulation in Holstein cows. Sixteen Holstein cows were used the test the efficacy of three superovulation regimens using Folltropin. In the case of regimen 1, CIDR plus with E2 capsule was inserted in cows at the random stage of estrous cycle and the total of 400 mg Folltropin V was adminstered twice a day for 4 days(Folltropin V group). In regimen 2, CIDR was inserted and 3.0 mg estradiol benzoate was administered i.m. next day and the total of 400 mg Folltropin was adminstered twice a day for 4 days(Folltropin V+EB group). For regimen 3, CIDR insertion was same as in the regimen 2 and the total of 400 mg Folltropin diluted with $10\%$ PEG 8,000 was administered once(Folttropin V+PEG 8,000 group). In all the regimens, CIDR were removed on 12th day and 45 mg dinoprost was administered i.m. simultaneously. The heat detected donors were administered 200 ug LH-RH and inseminated twice with 2 straws of frozen semen 12 hours apart. Embryo were collected using Foley catherter in each uterine homs on 6${\~}$8 days after inseminations. The evaluation of collected embryos were according to the IETS manual. The CL responses according to the superovulation treatments were 5.8, 20.6, 24.0 in the Folltropin V, Folltropin+EB and Folltropin V+PE 8,000 groups, respectively and there were significant different among the treatments(p<0.01). Transferable embyos collected were 3.6$\pm$2.4, 3.3$\pm$l.8 and 2.8$\pm$2.3, in the Folltropin V, Folltropin+EB and Folltropin V+PE 8,000 groups, respectively. Degenerated and unfertilized embryos in regimen 2 and 3 than regimen 1. These results indicates that superovulation treatments with both multiple injections and a single injection using PEG of Folltropin combined with CIDR insertion at the random stage of estrus cycle can be used to produce Holstein embryos.

• Journal of Embryo Transfer
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• v.18 no.2
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• pp.91-96
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• 2003

The aim of this study was conducted to evaluate the effect of sugar kinds and combination of various sugars on acrosome damage of post-thaw spermatozoa in canine. The extender used in this study was Tris-citric acid extender (Tris-buffer) supplemented with 20% Egg-yolk, 8% glycerol, 1% Equex STM paste, and 70 mM sugars such as monosaccharide (fructose and xylose) and disaccharide(trehalose). To evaluate of sugar combination, the sugars supplemented in Tris-buffer were combined such as control (fructose, xylose, trehalose), two combinations (Fru+Tre, Fru+Xyl, Tre+Xyl) and three combinations (Fru+Tre+Xyl). The acrosome damage rate of post-thaw spermatozoa in Eosin B & Fast Green stain in Fruc+Tre was higher than those in fructose, trehalose, xylose, Fruc+Xyl, Tre+Xyl, Fruc+Tre+Xyl (83.0$\pm$5.6 vs. 82.3$\pm$3.1%, 81.7$\pm$2.1%, 72.0$\pm$2.0%; 80.3$\pm$4.5%, 76.7$\pm$3.8%, 81.0$\pm$5.6). The motility after CASA analysis in Fru+Tre was higher than those in Fru+Tre+Xyl, Tre+Xyl, Fru+Xyl, Xylose, Trehalose, Fructose(79$\pm$6 vs 75$\pm$3, 74$\pm$8, 71$\pm$11, 70$\pm$4, 66$\pm$15, 63$\pm$ 12%). However, the progressive motility after CASA analysis in Fru+Tre group was higher than those in Fru+Tre+Xyl, Tre+Xyl, Fru+Xyl, Xylose, Trehalose, Fructose (67$\pm$7, 64$\pm$3, 62$\pm$6, 61$\pm$8, 60$\pm$2, 57$\pm$13, 53$\pm$10%). The results indicated that the acrosome damage & progressive motility of post-thaw spermatozoa in 70 mM Fruc+Tre (two combination) following Eosin B & Fast Green stain and CASA analysis.

• Journal of Food Hygiene and Safety
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• v.23 no.4
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• pp.304-308
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• 2008

We investigated temperature management for refrigerated foods in large discount markets, department stores, and convenience stores. Eleven stores in the Seoul area were used to examine temperature maintenance for frozen and refrigerated foods, including soybean curds (tofu), fish surimi, mook, wet noodles, kimbab, and salads. The surficial and central temperatures of foods in a refrigerator and a freezer were examined. While the difference between the highest ($7.5^{\circ}C$) and the lowest ($6.4^{\circ}C$) temperature spaces in a refrigerator was $1.1^{\circ}C$, the corresponding difference between the highest ($8.9^{\circ}C$) and lowest ($7.5^{\circ}C$) food surface temperatures was $1.4^{\circ}C$. The average temperatures of both chilled food surfaces and refrigerator spaces were $7^{\circ}C$ (max. $22.9^{\circ}C$) and 8.2 degrees C (in. $-0.4^{\circ}C$), respectively. The temperatures of chilled food surfaces were $6.1{\times}10.6^{\circ}C$ for soybean curds, $6{\sim}12.3^{\circ}C$ for fish paste, $2.3{\times}18.2^{\circ}C$ for kimbab, $4.6{\times}12.2^{\circ}C$ for salads, $3.4{\times}12.6^{\circ}C$ for wet noodles, and $7.1{\times}19^{\circ}C$ for mook. Our results indicate that chilled foods require careful management for storage at temperatures below $10^{\circ}C$ with careful recording of the warmest area of the refrigerator.

• Journal of Food Hygiene and Safety
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• v.24 no.4
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• pp.299-306
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• 2009

Aflatoxin (AF) and Ochratoxin A (OTA) are carcinogenic and possible carcinogenic mycotoxins respectively produced by Aspergillus spp or Penicillium spp. The study for contamination survey and proposal for reduction of mycotoxin in red pepper were carried out. 192 samples were collected at such various stages and markets as pre/post-harvest stages, internet shopping mall /super-market and small stakeholder mill/geographically indicated company. As only 2 samples were positive for aflatoxin, so contamination rate was 1.04%. In the meanwhile, contamination rate for ochratoxin A was 21.88% and a various amount of OTA was detected in 42 positive samples. 6 samples were found to be contaminated at higher level than $5\;{\mu}gkg^{-1}$ for ochratoxin A, which was established recently as a maximum permissible limit in korea. There was no difference in degree of contamination with regard to cultivation type because any mycotoxin was not found at all in both organically and conventionally grown red pepper. But, there was statistically significant difference in the process of manufacturing. Finished products were OTA-contaminated at a level of $2.32\;{\pm}\;6.54\;{\mu}gkg^{-1}$(mean ${\pm}$ SD), even though OTA was not detected in deep frozen red peppers right after long term storage. And contamination for OTA was a level of $0.33\;{\pm}\;0.91\;{\mu}gkg^{-1}$(mean ${\pm}$ SD) in red paprika powder after uv sterilization, while the contamination for OTA was $2.78\;{\pm}\;4.49\;{\mu}kg^{-1}$(mean ${\pm}$ SD) in non-uv sterilized powder. In addition, our investigation shows that higher OTA contamination occurred in some of famous brand products sold in super-market and domestic products than products collected through on-line shopping or from small stakeholder mills and imported products respectively, however, difference was not statistically significant.

• The Korean Journal of Nuclear Medicine
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• v.30 no.4
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• pp.484-492
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• 1996

To detect ischemic tissue in experimental model of cerebral ischemia made by middle cerebral artery(MCA)-occlusion, we acquired triple image of $^{99m}Tc$-glucarate, [$^{18}F$]fluoro-deoxyglucose (FDG), and 2,3,5- triphenyltetrazolium (TTC) staining. We made cerebral infarction either with reperfusion (after occlusion of 2 hours) or without reperfusion in 10 Sprague-Dawley rats by inserting thread to MCA through internal carotid artery. After 22 hours, we injected 740 MBq of $^{99m}Tc$-glucarate and 55.5 MBq of [$^{18}F$]FDG through tail vein. Each 1 mm slice of rat brains was frozen and exposed to imaging plate for 20 minutes in freezer to get an [$^{18}F$]FDG image. After 20 hours enough to fade radioactivity of [$^{18}F$]FDG, the slices were again imaged by BAS1500 for $^{99m}Tc$-glucarate uptake. Finally, these brain tissues were stained with TTC. Semi-quantitative visual analysis was done by grading 0 to 3 points according to the degree of uptakes($^{99m}Tc$-glucarate) and decreased uptakes([$^{18}F$]FDG and TTC). Ten rats survived with neurologic symptoms. TTC staining confirmed the development of infarction. The size of the infarction was relatively larger in the group without reperfusion. [$^{18}F$]FDG images were similar to TTC-stained images. However, we found regions with intermediate uptake which were not stained with TTC. We found regions with intermediate [$^{18}F$]FDG uptake where TTC staining was normal. $^{99m}Tc$-glucarate uptake was round only in TTC non-stained region. In the TTC stained regions, there were no uptake of $^{99m}Tc$-glucarate. We could not find clear relation between $^{99m}Tc$-glucarate uptake with [$^{18}F$]FDG uptake. This was partly because percent uptake of $^{99m}Tc$-glucarate was so small (less than 1 percent of injected dose) and because there were quite heterogeneity of patterns of [$^{18}F$]FDG uptake and TTC. With these findings, we could conclude that $^{99m}Tc$-glucarate were taken up only in part of ischemic tissues which were proven to be nonviable. The establishment of MCA-occluded rat model with or without reperfusion and triple imaging for $^{99m}Tc,\;^{18}F$ and TTC helped the characterization of $^{99m}Tc$-glucarate uptakes. Further work is needed to clarify the meaning or diversities or [$^{18}F$]FDG and TTC and their relation with $^{99m}Tc$-glucarate.

• Korean Journal of Animal Reproduction
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• v.24 no.1
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• pp.69-76
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• 2000

This study was carried out to improve of effective culture system on development of IVM/IVF/IVC bovine embryos. The cumulus-oocyte-complexes (COCs) collected from Korean cattle ovaries harvested at a local abattoir were matured in 50 ${mu}ell$ of TCM199 supplemented with 10% fetal bovine serum (FBS) and hormones (35 $\mu\textrm{g}$/$m\ell$ FSH, 10 $\mu\textrm{g}$/$m\ell$ LH, 1$\mu\textrm{g}$/$m\ell$ estradiol 17 $\beta$ under paraffin oil at 39$^{\circ}C$ in a humidified atmosphere of 5% $CO_2$in air. At 24 hrs after culture, matured oocytes were fertilized in vitro for 22~24 hrs with motile semen in which obtained by centrifugation of a frozen thawed semen on Percoll-density gradients (45% vs. 90%) at 500 g for 20 min. The presumptive zygotes were divided into three experimental groups. Single egg (Group 1), 25 (Group 2) or 50 eggs (Group 3) were cultured on cumulus cell in 50 ${mu}ell$ TCM199 supplement with 10% FBS for 6~9 days after fertilization. In vitro developmental rates into the blastocysts in the groups 2 and 3 were significantly (P＜0.05) higher than those of group 1 (37,27 vs. 6%, respectively). Cell number of blastocysts obtained in groups 2 and 3 at day 8 were significantly (P${mu}ell$) resulted in higher developmental competence and cell number of bovine blastocysts produced in vitro than those the culture of single embryos with cumulus cells.

• Korean Journal of Food Science and Technology
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• v.17 no.6
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• pp.495-499
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• 1985

To develope a process by which liquid foods can be stored in the liquid state at the frozen storage temperature, suitable cryoprotectants were selected. Orange juice, chosen as an example of liquid foods, was stored with combined cryoprotectants at $-15^{\circ}C$, and quality changes of orange juice during storage were evaluated. Among 7 cryoprotectants tested, NaCl solution had lower initial freezing point than others, and initial freezing points of glucose, fructose, glycerol, propylene glycol and citric acid were close to each other. Considering flavor quality of orange juice, cryoprotectants suitable for reducing freezing point of orange juice were glucose, fructose, glycerol, and citric acid. Combined cryoprotectants for reducing freezing point of 3 and 4 folds concentrated orange juice to $-15^{\circ}C$ consisted of 10% glucose, 8% frutose, 4.6% glycerol and 3% citric acid, and 5.5% glucose, 4.5% fructose, 4.6% glycerol, and 3% cirtric acid, respectively. When destruction of ascorbic acid, sedimentation volume and sensory flavor score of orange juice stored with combined cryoprotectants at $-15^{\circ}C$ and the control stored at $-18^{\circ}C$ were compared, there were no significant differences. These results indicated that liquid foods with suitable combined cryoprotectants could be stored at $-15^{\circ}C$ or below in the liquid state without adverse effect on quality of the stored products.