• Microbiology and Biotechnology Letters
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• v.13 no.4
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• pp.409-415
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• 1985

This study has been carried out in order to investigate the bacterial quality of fish meat paste products and the characteristics of isolated thermodurics from the products. Twenty samples of crab-flavored fish stick (Kematsal), 23 samples of plate fish meat paste (Panomuk, Kamaboko), 5 samples of fried fish meat paste (Tigimomuk), 2 samples of roasted fish meat paste (Puduromuk, Chikuwa), 20 samples of fish sausage were collected from processing plants and supermarkets in Pusan, Korea during the period from May to October in 1984. The results obtained are as follows. Amont the samples collected from supermarkets, roasted fish meat paste and fried fish meat paste marked hish counts in coliforms and fungi while very low in the samples of crab-flavored fish stick and plate fish meat paste. Salmonella was not detected in all the samples examined and Staphylococcus aureus was detected only in fried fish meat paste, Thermoduric bacteria were detected less than 10$^2$/g in the samples of crab-flavored fish stick and plate fish meat paste, which might come from subsidiary materials such as starch and seasonings. Among the isolated bacteria, distribution of the proteolytics were more than 87％ and the lipolytics were less than 20％. Gram positive bacteria was more than 70％ in crab-flavored fish stick and plate fish meat paste, 47.3％ in fried fish meat paste. And rod in shape was almost more than 90％ in all the samples. The most heat resistant bacterium isolated from the samples was identified as a Bacillus licheniformis(named B. licheniformis CR-11). The strain showed strong proteolytic activity and also grew well at above 2$0^{\circ}C$. The growth rate and generation time of CR-11 strain were 0.31 hr$^{-1}$ , 2.24 hr at 2$0^{\circ}C$, 0.64 hr$^{-1}$ , 1.09 hr at 3$0^{\circ}C$ and 0.78 hr$^{-1}$ , 0.89 hr at 35$^{\circ}C$. Heat resistance value of the spores of CR-11 strain suspended in phosphate buffer solution was D$_{85}$ $^{\circ}C$=41.9 min, D$_{90}$ $^{\circ}C$=27.9 min, D$_{95}$ $^{\circ}C$=10.2 min, D$_{100}$ $^{\circ}C$=4.3 min (Z=13.8$^{\circ}C$)

• Journal of Embryo Transfer
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• v.13 no.3
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• pp.277-289
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• 1998

To establish a system for sperm swim-up separation through sucrose layer, indiscreet sperm migration should sufficiently to block but movement of sperm shouldn't inhibit. Thus, the effects of sucrose levels in sucrose layer, incubation times and types of sucrose layer on sperm separation were examined. And the results obtained were as follows; 1. Layer of 10mM sucrose inhibited sperm swim-up migration through sucrose layer. 2. Incubation for 25 minutes without sucrose layer significantly increased sperm swim-up migration. However, incubation for 10 minutes to induce swim-up through sucrose layer significantly stimulated sperm migration and maintained sperm movement. 3. There was no significant difference between Type I and Type II in barrier effect of sucrose layer. However, sucrose layer of Type II with shorter distance of barrier was efficient for sampling. To elucidate a function of follicular fluid on sperm chemotaxis using in vitro system of sucrose layer of Type II and incubation for 10 minutes, the effects of dilution, heat treatment, and protein and lipid extracts of follicular fluid on sperm swim-up separation were examined. And the results obtained were as follows; 4. Follicular fluid stimulated sperm migration and movement, and significantly-attracted capacitated-sperm at 10% level. 5. Follicular fluid heated at 55$^{\circ}C$ for 30 minutes maintained the effect of follicular fluid stimulating sperm migration and movement. 6. Follicular protein stimulated sperm movement that was reduced by filtration of the protein. 7. Follicular lipid didn't significantly stimulate sperm migration and movement. 8. Both of follicular protein and lipid reduced the effect of follicular fluid stimulating sperm migration and movement. In conclusion, sucrose layer could be used for a barrier against indiscreet sperm migration by swim-up. And follicular fluid stimulated migration and movement of sperm and attracted capacitated-sperm through sucrose layer. Especially, heat-resistant protein of follicular fluid stimulated sperm migration.

• Journal of Applied Biological Chemistry
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• v.60 no.4
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• pp.383-390
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• 2017

Regarding the facts that fat, which is easily oxidized, is one of the major responsible factors affecting the quality of aroma, and polyphenol compounds including chlorogenic acid (CGA) contribute the anti-oxidative activities to coffee, we investigated fat oxidation, conversion of CGA, and changes of anti-oxidative activities according to the degree of roasting and storage of 60 days. We found that the amount of extractable fat by diethyl ether is increased as the coffee beans are roasted longer. Furthermore, the acidity values of the fat are increased from $8.91{\pm}0.16$ to $17.81{\pm}0.11$, and $10.37{\pm}0.27$ to $17.93{\pm}0.09$ in the medium and dark roasted coffee beans, respectively, while it is increased from $4.47{\pm}0.11$ to $11.89{\pm}0.18$ in the green coffee bean after 60 days. The CGA contents in the coffee beans were decreased from $310{\pm}8.2$ to $282{\pm}11.2$, then to $58{\pm}0.0mg$ in 10 gr of the green, medium and dark beans, respectively, and were not changed significantly during the storage period. However, the anti-oxidative activities measured by 2,2-diphenyl-1-picrylhydrazyl and 2,2'-azinobis-(3-ethylbenzothiazoline-6-sulfonic acid radical scavenging assays were not significantly different among the green, medium, and dark coffee beans during the storage period. Furthermore, antioxidant reactive element-luciferase assay showed that biological anti-oxidative activities were increased as coffee beans were more roasted and stored longer. As the total polyphenolic contents in the beans were significantly decreased by roasting, the results suggests that other molecules, such as, Maillard reaction products might play substantial role in anti-oxidative activity and influence cup quality of coffee.

• Journal of the Korean Magnetics Society
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• v.15 no.2
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• pp.100-105
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• 2005

$Ni_{0.9}Zn_{0.1}Fe_2O_4$ nanoparticles have been prepared by a sol-gel method. The structural and magnetic properties have been investigated by DTA/TGA, XRD, SEM, and $M\ddot{o}ssbauer$ spectroscopy, VSM. $Ni_{0.9}Zn_{0.1}Fe_2O_4$ powder that was annealed at $300^{\circ}C$ has spinel structure and behaved superparamagnetically. The estimated size of superparammagnetic Ni-Zn ferrite nanoparticle is around 10 nm. The hyperfine fields at 13 K for the A and B patterns were found to be 533 and 507 kOe, respectively. The blocking temperature ($T_B$) of superparammagnetic $Ni_{0.9}Zn_{0.1}Fe_2O_4$ nanoparticle is about 250 K. The magnetic anisotropy constant and relaxation time constant of $Ni_{0.9}Zn_{0.1}Fe_2O_4$ nanoparticle were calculated to be $1.6\times10^6\;ergs/cm^3$ and ${\tau}_0=5.0{\times}10^{-13}$ s, respectively. Also, Temperature increased up to $43^{\circ}C$ within 10 minutes under AC magnetic field of 7 MHz. It is considered that $Ni_{0.9}Zn_{0.1}Fe_2O_4$ powder that was annealed at $300^{\circ}C$ is available for biomedicine application such as hyperthermia, drug delivery system and contrast agents in MRI.

• Korean Journal of Materials Research
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• v.11 no.5
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• pp.367-371
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• 2001

In this paper, theS $r_2$(T $a_{1-x}$ , N $b_{x}$)$_2$ $O_{7}$(STNO) films among ferroelectric materials having a low dielectric constant for metal-ferroelectric-semiconductor field effect transistor(MFS-FET) were discussed. The STNO thin films were deposited on p-type Si(100) at room temperature by co-sputtering with S $r_2$N $b_2$ $O_{7(SNO)}$ ceramic target and T $a_2$ $O_{5}$ ceramic target. The composition of STNO thin films was varied by adjusting the power ratios of SNO target and T $a_2$ $O_{5}$ target. The STNO films were annealed at 8$50^{\circ}C$, 90$0^{\circ}C$ and 9$50^{\circ}C$ temperature in oxygen ambient for 1 hour. The value of x has significantly influenced the structure and electrical properties of the STNO films. In the case of x= 0.4, the crystallinity of the STNO films annealed at 9$50^{\circ}C$ was observed well and the memory windows of the Pt/STNO/Si structure were 0.5-8.3 V at applied voltage of 3-9 V and leakage current density was 7.9$\times$10$_{08}$A/$\textrm{cm}^2$ at applied voltage of -5V.of -5V.V.V.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.23 no.4
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• pp.280-288
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• 1990

Quality stability of dried lavers during roasting and storage was investigated by measuring the changes of pigment contents including chlorophyll a, carotenoids and biliproteins, the content of trypsin indigestible substrates(TIS), in vitro apparent protein digestibility, and dietary fiber. In heat treatment or roasting of dried laver, carotenoids and chlorophyll a were found to be more stable than biliproteins. Chlorophyll a and carotenoids were retained more than $85\%$ during roasting for 1 hour at $120^{\circ}C$ while biliproteins were retained only $10\%$ at the same temperature. The in vitro digestility of dried layers tended to increase with raising the roasting temperature. The in vitro digestibility of $85\%$ for the roasted laver at $100^{\circ}C$ was higher than that observed in the control of $80\%$. There was a correlation between the decrease in TIS and biliproteins as the laver was roasted. The soulble dietary fiber(SDF) content was substantially increased by heat treatment. The extent of protein digestiblility appeared to be related to the increase of SDF content. In the storage of roasted lavers under both water activities 0.1 and 0.65, the loss of the pigments and TlS were markedly retarded at Aw 0.1. Chlorophyll a was retained about $20\%$ at aw 0.65 and $75\%$ at aw 0.1 after 20 week sto-rage. At worst, more than $90\%$ of the carotenoids were lost at aw 0.65 after 20 week, while biliproteins were comparatively stable at the same water activity. TIS decreased about $15\%$ and in vitro apparent protein digestibility increased up to $92\%$ at aw 0.65 during storage.

• Journal of the Korean Society of Food Science and Nutrition
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• v.41 no.4
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• pp.550-560
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• 2012

This study was performed to investigate the physicochemical properties of sea urchin ($Anthocidaris$ $crassispina$, $Pseudocentrotus$ $depressus$, $Hernicentrotus$ $pulcherrimus$) roe as a processed or canned food by steaming treatment. Proximate compositions of $A.$ $crassispina$ roe and $P.$ $depressus$ roe were similar, but water, crude ash, and carbohydrate contents of $H.$ $pulcherrimus$ roe showed little differences. Proximate compositions of sea urchin roe showed slight differences with steaming time, raw samples showed no differences. Glycine content of the three raw sea urchin roe samples showed the highest concentration among free amino acids, followed by arginine, alanine, and lysine, in order. Total free amino acid contents of raw sea urchin roe were 754.70 mg% ($A.$ $crassispina$), 567.75 mg% ($P.$ $depressus$), and 449.44 mg% ($H.$ $pulcherrimus$). Total free amino acid content of 5 min steaming sample was highest among steaming and canning conditions. ATP, ADP, and AMP contents of raw $P.$ $depressus$ roe sample was higher than those of $A.$ $crassispina$and $H.$ $pulcherrimus$ roe. Major fatty acids of the three raw sea urchin roe samples were myristic acid, palmitic acid, and EPA. S.F.A. content of raw samples of $A.$ $crassispina$and $H.$ $pulcherrimus$ roe was higher than U.F.A content, whereas U.F.A. content of $P.$ $depressus$ roe was highest among the three raw samples. For minerals K, P, Fe, and Zn contents were highest in $A.$ $crassispina$roe while Ca, Mg, Na, and Cu contents were highest in $H.$ $pulcherrimus$ roe. For heavy metals, Cd, Pb and As were detected in all samples in trace amounts under the criteria of the Korea food codex.

• Journal of Dairy Science and Biotechnology
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• v.32 no.2
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• pp.93-100
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• 2014

In general, whey obtained from various cheese batches is being reused, so as to improve the texture and to increase the yield and the nutrient value of the various final milk-based products. In fact, re-usage of whey proteins, including whey cream, is a common and routine procedure. Unfortunately, most bacteriophages can survive heat treatments such as pasteurization. Hence, there is a high risk of an increase in the bacteriophage population during the cheese-making process. Whey samples contaminated with bacteriophages can cause serious problems in the cheese industry. In particular, the process of whey separation frequently leads to aerosol-borne bacteriophages and thus to a contaminated environment in the dairy production plant. In addition, whey proteins and whey cream reused in a cheese matrix can be infected by bacteriophages with thermal resistance. Therefore, to completely abolish the various risks of fermentation failure during re-usage of whey, a whey treatment that effectively decreases the bacteriophage population is urgently needed and indispensable. Hence, the purpose of this review is to introduce various newly developed methods and state-of-the-art technologies for removing bacteriophages from contaminated whey and whey products.

• Journal of Food Hygiene and Safety
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• v.29 no.2
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• pp.158-163
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• 2014

In this study, two commercial PCR and ELISA test kits were examined for identification of eight animal species (beef, pork, chicken, duck, turkey, goat, lamb, and horse) from raw meat and meat products in Korea. The detection limit in RAW meat ELISA kit$^{(R)}$ on three types of meat samples blended with beef, pork and chicken, demonstrated that all meat species were differentiable down to 0.2%. RAW meat ELISA kit$^{(R)}$ on animal species resulted in differentiation rate of 94.5% for beef, 93.3% for pork, 90% for lamb, and 100% for chicken, duck, turkey, goat, and horse. In contrast, Powercheck Animal Species ID PCR kit$^{TM}$ resulted in 100% specificity at 0.05% limit of detection for all meat species. The detection limit of Cooked Meat ELISA kit$^{(R)}$ on mixed meat samples heat-treated with different temperatures and times, resulted in 0.1% for all heat-treated mixed meat except for chicken at 1.0%. Additionally, ELISA kit on sixty meat products resulted in specificity of 31.8% for ham, 13.6% for sausages, and 12.5% for ground processed products, and relatively low rate for more than 2 types of mixed meats. On the contrary, meat species differentiation using PCR kit showed higher percentage than that using ELISA kit$^{(R)}$: 50.0% for ham, 41.7% for sausages, and 28.6% for ground processed meat. Futhermore, PCR kit on 54 dried beef meats detected pork genes in 13 products whereas ELISA kit showed negative results for all products. Hence, the possibility of cross-contamination during manufacturing process was investigated, and it was found that identical tumblers, straining trays, cutters and dryers were used in both beef and pork jerky production line, suggesting the inclusion of pork genes in beef products due to cross-contamination. In this study, PCR and ELISA test kits were found to be excellent methods for meat species differentiation in raw meat and heat-processed mixed meat. However, lower differentiation rate demonstrated in case of meat processed products raised the possibility of inclusion of other species due to cross-contamination during manufacturing process.

• Korean Journal of Mineralogy and Petrology
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• v.33 no.4
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• pp.407-417
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• 2020

The capacity of the designated landfill site for asbestos-containing waste is approaching its limit because the amount of asbestos-containing slate is increasing every year. There is a need for a method that can safely and inexpensively treat asbestos-containing slate in large capacity and at the same time recycle it. A cement kiln can be an alternative for heat treatment of asbestos-containing slate. We intend to develop a pilot scale device that can simulate the high temperature environment of a cement kiln using a high temperature plasma reactor in this study. In addition, this reactor can be used to inactivate asbestos in the slate and to synthesize one of the minerals of cement, to confirm the possibility of recycling as a cement raw material. The high-temperature plasma reactor as a pilot scale experimental apparatus was manufactured by downsizing to 1/50 the size of an actual cement kiln. The experimental conditions for the deactivation test of the asbestos-containing slate are the same as the firing time of the cement kiln, increasing the temperature to 200-2,000℃ at 100℃ intervals for 20 minutes. XRD, PLM, and TEM-EDS analyses were used to characterize mineralogical characteristics of the slate before and after treatment. It was confirmed that chrysotile [Mg3Si2O5(OH)4] and calcite (CaCO3) in the slate was transformed into forsterite (Mg2SiO4) and calcium silicate (Ca2SiO4), a cement constituent mineral, at 1,500℃ or higher. Therefore, this study may be suggested the economically and safely inactivating large capacity asbestos-containing slate using a cement kiln and the inactivated slate via heat treatment can be recycled as a cement raw material.