• Korean Journal of Fisheries and Aquatic Sciences
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• v.30 no.1
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• pp.72-78
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• 1997

The levels of reducing sugars, organic acids and fatty acids, known as precursors of major flavors induced from dried sellfish, were analyzed to investigate their behaviors during drying process. Free reducing sugar contents were markedly decreased in all samples by boiling, Its content in Blue mussel and Short-necked calm samples significantly decreased after drying process. Among the eight different organic acids from blue mussel, Short-necked calm and Pacific oyster samples, succinic acid in blue mussel and short-necked calm samples was measured with $74.9\%\;and\;67.4\%$, respectively. In the sample of Pacific oyster, succinic acid content was found to be $38.4\%$, but pyroglutamic acid content was the highest level with $41.6\%$. Contents of organic acids with exception succinic acid were significantly reduced in all three samples of sun-dried or hot-air dried. The content of succinic acid in the samples of sun-dried and hot-air dried pacific oyster reduced to $53.0\%\;and\;44.2\%$, respectively, but relatively small decrease $(29.0\%\;and\;10.0\%)$ was observed in sun-dried and hot-air dried short-necked calm samples, respectively. Content of polar lipid with the major fatty acids profile of C16:0, C16:1, C20:5 and C22:6 was consisted of $59.1\%,\;66.7\%\;and\;42.4\%$, respectively, in blue mussel, short-necked calm and pacific oyster samples and the content of polyene fatty acids was appeared to be $40.5\%,\;48.6\%\;and\;48.9\%$, respectively. Relatively high peroxide value in all boiled-dried products samples was found to be $41.64\~86.80\;meq/kg$ sample. Carbonyl value in boiled-dried products samples was found to be $15.55\~27.99\;meq/kg$, but its value in broiled products samples was significantly high level of $127.6\~136.5\;meq/kg$.

• Journal of the Korean Society of Food Science and Nutrition
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• v.13 no.1
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• pp.57-63
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• 1984

This study was designed to compare the quality characteristics of freeze and spray dried red ginseng extract powders(RGEPs) by drying methods, which have been required to maintain the stability for the quality. Chemical compositions, major ginsenoside contents and color intensities of these Products were compared by drying conditions. The moisture absorption rates and optical densities also were compared during storage under maltreatment conditions of a various relative humidities (75, 86and 92 RH) and two different temperatures (37 and $50^{\circ}C$). It was found that decreases of total major ginsenosides contents in freeze and spray dried RGEPs were 5.4 % to 6.7 % during storage for 6 months at $37^{\circ}C$, 75 % RH. When these products packaged with inner seal of Al-foil laminate paper (Al-foil; 9 ${\mu}m$) were stored for 6 months at $37^{\circ}C$, 75 % RH. the moisture absorption rates of freeze and spray dried RGEPs were ranged 42 % to 82 %, 8 % to 16 %, respectively. In storage for 6 months at $37^{\circ}C$, 86 % RH, spray dried RGEP was higher in brown pigment($400{\sim}490nm$) than freeze dried RGEP while freeze dried was higher in pyrazine (278 nm), HMF and furfural (285 nm) than spray dried RGEP. It was found that RGEPs showed a strong anti-oxidative activity by electron donating ability to DPPPH, but there was no significant difference between freeze and spray dried RGEPs.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.18 no.6
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• pp.511-518
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• 1985

As one of the sensory factors for characterizing food quality, volatile compounds have been particularly contributed to sensory evaluation of fermented sea foods in Korea. But no chemical investigation of the volatile compounds of fermented anchovy as one of the most favored fermented sea food products has been reported. Accordinglry, for a series study of processing of low salt fermented sea foods, changes in volatile compounds and fatty acid composition of fermented anchovy with low salt contents ($4\%$ of salt contents) were experimented fermentation comparing with conventional fermented anchovy ($20\%$ of salt contents). Total lipid of raw anchovy was composed of $77.6\%$ of neutral lipid, $22.1\%$ of phospholipid and $0.3\%$ of glycolipid. And polyenoic acid was held $39.8\%$ of fatty acid composition of total lipid and the major fatty acids in those were $C_{22:6},\;C_{20:5}$. During the fermentation of anchovy saturated fatty acid ($C_{16:0},\;C_{18:0},\;C_{l4:0}$) and monoenoic acid ($C_{16:1},\;C_{18:1}$) increased while polyenoic acid ($C_{22:6},\;C_{20:5}$) decreased greatly. Thirty-eight kinds of volatile component from the whole volatile compounds obtained from fermented anchovy after 90 days fermentation were identified, and composed of some alcohols (8 kinds), carbonyl compounds (9 kinds), hydrocarbons (8 kinds) and fatty acids (8 kinds). During fermentation 8 kinds of volatile acids, 5 kinds of amines, 9 kinds of carbonyl compounds were also detected. Those volatile acids such as acetic acid, isovaleric acid, propionic acid, n-butyric acid were the major portion of total volatile fatty acids of 60 days fermented anchovy prepared with low salt contents. On the other hand, carbonyl compounds such as ethanal, 3-methyl butanal, hexanal, 2-methyl propanal were the major ones, while TMA held the most part of volatile amines in fermented anchovy with low salt contents after 60 days. Conclusively, there was little difference in composition of volatile components, but merely a little difference in content of those between low salt fermented anchovy and conventional fermented ones.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.33 no.1
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• pp.9-15
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• 2000

To investigate changes of components in salt-fermented anchovy, Engraulis japonims sauce during fermentation, various chemical properties were examined at $1.5{\~}3$ months interval during 18 months fermentation. Moisture content and pH were decreased slightly, but the contents of VBN and crude protein, total and amino nitrogen, hydrolytic degree and absorbance at 453 nm were increased gradually during fermentation. On the other hand, ash content and salinity showed almost no change. Hk and uric acid were the most abundant in ATP related compounds, ranging from $80.1{\%}\;to\;92.7{\%}$ in salt-fermented anchovy sauce during the fermentation, After 18 months of fermentation the sauce was rich in free amino acids, such as glutamic acid, leucine, alanine, lysine, isoleucine, valine in that order.

• Journal of Food Hygiene and Safety
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• v.33 no.4
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• pp.280-288
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• 2018

In this study, an approach for the analysis of the five cephalopod species (octopus, long-arm octopus, squid, wet-foot octopus, beka squid) consumed in the Republic of Korea is developed. The samples were collected from the Southeast Asian countries Thailand, Indonesia, Vietnam, and China. The SYBR-green-based real-time qPCR method, based on the mitochondrial DNA genome of the five cephalopods was developed and validated. The intergroup variations in the mitochondrial DNA are evident in the bioinformatic analysis of the mitochondrial genomic DNA sequences of the five groups. Some of the highly-conserved and slightly-variated regions are identified in the mitochondrial cytochrome-c-oxidase subunit I (COI) gene, 16s ribosomal RNA (16s rRNA) gene, and 12s ribosomal RNA (12s rRNA) gene of these groups. To specify each five cephalopod groups, specific primer sets were designed from the COI, 16s rRNA and 12s rRNA regions. The specific primer sets amplified the DNA using the SYBR-green-based real-time PCR system and 11 commercially secured animal tissues: Octopus vulgaris, Octopus minor, Todarodes pacificus, Dosidicus gigas, Sepia esculenta, Amphioctopus fangsiao, Amphioctopus aegina, Amphioctopus marginatus, Loliolus beka, Loligo edulis, and Loligo chinensis. The results confirmed by a conveient way to calculate relative amplification levels between different samples in that it directly uses the threshold cycles (Ct)-value range generated by the qPCR system from these samples. This genomic DNA-based molecular technique provides a quick, accurate, and reliable method for the taxonomic classification of the animal tissues using the real-time qPCR.

• Journal of the Korean Society of Food Science and Nutrition
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• v.14 no.1
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• pp.1-12
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• 1985

In an attempt todetermine the optimum heat treatment, the changes in TIS content and in vitro protein digestibility of squid, shrimp, oysterand pollock under various heating conditions were studied. The effect of drying method and cold storage on the in vitro digestibility and TIS content were also studied. Optimal boiling conditions were 1 min, for squid, 0.5min. for oyster(eviscerated), 1 min. for whole oyster, and 5 min. for pollock. Steaming times that yieled products with the highest in vitro digestibility value were: 1 min. at $100^{\circ}C$ for squid, 1 min, at $88^{\circ}C$ for oyster and $1{\sim}2.5min$. at $100^{\circ}C$ for pollock. All of freeze dried samples showed the highest in vitro digestibility value and sundried one were comparble to freeze dried samples except high fat level or noneviscerated samples. Fat content was the nain inhivbitory factor of the seafood enzymic digestion during processing and storage. The multi-enzyme assay, used to predict the quality change of dried seafoods stored in a cold room for long periods of raw seafoods treated with various heating methods, offers many advantages over the convetional methods of determining protein quality.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.34 no.2
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• pp.119-124
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• 2001

In Conventional process, sugaring and seasoning step were combined during seasoning process of Changran-Jeotgal. While, in the case of Improved process, sugaring and seasoning step were separated and agitation was employed in order to control moisture content and improve taste. The addition of $20\%$ of corn syrup and agitation with 10 rpm for 4 hours at $20^{\circ}C$ were carried out to optimize the seasoning process in Changran-Jeotgal. From above results, quality estimation of Changran-Jeotgal manufacturing process, such as chemical and microbiological changes, there were little difference for salinity, pH, VBN value, crude fat and crude protein between Improved process and Conventional one, However water activity of Changran-Jeotgal produced by the Improved process was lower with 0.82 than that of Conventional one with 0.90. And the sensory evaluation showed that Improved process produced more favorable products; By regional groups, Seoul residents favored them more than Busan ones and by age, teen-aged like them best.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.34 no.5
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• pp.488-492
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• 2001

To investigate changes of components in salt-fermented big eyed herring, Harengula zunasi sauce during fermentation, various chemical properties were examined at $2\~3$ months intervals during 18 months of fermentation. The hydrolytic degree increased sharply until 5 months of fermentation and showed the gentle increasement after that. On the other hand, the content of total and amino nitrogen increased gradually during 18 months of fermentation, The hypoxanthine and uric acid were the most abundant in ATP related compounds, ranging from $81.7\%\;to\;90.1\%$. After 18 months of fermentation, sauce was rich in free amino acids such as glutamic acid, aspartic acid, alanine, lysine, threonine in that order.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.34 no.5
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• pp.483-487
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• 2001

As a part of basic investigation for utilizing of cuttle bone as a calcium source, we examined on the extraction methods (calcining at $800^{\circ}C$ for 2 hrs, autoclaving at $121^{\circ}C$ for 10 hrs and ultrasonic treatments at $60^{\circ}C$ for 10 hrs) as a pretreatment methods for preparation of calcium-based powder from cuttle bone, The color of calcined calcium-based powder from cuttle bone was white, while that treated by other methods was light yellow. The calcium content in calcined calcium-based powder was $70.5\%$, and revealed high about 2 times compared to those pretreated by other methods. And, calcium solubility in calcined calcium-based powder was improved 22 times compared to raw cuttle bone powder, Among calcining, autoclaving and ultrasonic treatments as a pretreaoent methods for preparation of calcium-based powder from cuttle bone, calcining treatment was superior to other methods on the aspect of color, calcium solubility and purity of calcium-based powder, Judging from X-ray diffraction pattern of calcined calcium-based powder, most of calcium was present as a form of calcium oxide, But, pH of calcined calcium-based powder revealed strong alkali of pH 12.9. This pH value might invoke health risk in using food resource. Therefore, for utilization effectively calcined calcium-based powder from cuttle bone, it requires a suitable treatment such as adjustment of pH to neutral condition.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.34 no.5
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• pp.478-482
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• 2001

This study was conducted to get a knowledge on food components of cuttle bone (CB) as a food resource. The yields and ash contents of CB were about $7.5\%$ on whole cuttle fish and about $90\%$ on dry basis, respectively, The contents of heavy metal might not invoke health risk in using food resource, The major mineral of CB was calcium as about $22\%$ in content. The yields, proximate compositions, heavy metal and mineral contents were not significantly different between domestic and imported CB. Judging from X-ray diffraction pattern, most of calcium in CB was present as a form of calcium carbonate (CC), and scanning electron micrograph showed irregular form. Buffering capacity of CB showed strongly at pH 7, and its pattern was the same as shown in that of CC, And CB solution showed a very high degree in turbidity comparing to that of CC solution. The solubility of CB was superior to that of CC, but inferior to those of calcium powders on the market, It was concluded from above results that CB could be effectively utilized as a calcium source.