• Korean Journal of Fisheries and Aquatic Sciences
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• v.29 no.3
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• pp.279-286
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• 1996

Cultivated tilapia (Oreochromis niloticus) in the fresh water were acclimated to the sea water to improve palatability of the fish meat. Physicochemical properties in the rigor mortis of those fish meats were investigated during storage at $0^{\circ}C,\;10^{\circ}C\;and\;20^{\circ}C$. The faster onset of rigor mortis was occurred in acclimated meat than fresh water cultivated meat. Both meats stored at $0^{\circ}C$ showed faster figro mortis than at $10^{\circ}C\;and\;20^{\circ}C$. Significant difference was not observed between the breaking strength and the rigor index. The breaking strength reached maximum over 12hrs after death and then gradually declined, and the rigor index was slowly increased and reached maximum over 18hrs after postmortem. Low temperature and acclimation to the sea water affected the degradation of adenosine triphosphate (ATP), accumulation of inosine monophosphate (IMP) or lactate. These results suggest that the palatability of tilapia muscle cultivated in the fresh water could be improved by acclimation to the sea water which induces the prerigor at the early state of postmortem and the physical changes of fish muscle.

• Korean Journal of Food Science and Technology
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• v.27 no.4
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• pp.471-477
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• 1995

Extractive nitrogen, free amino acids, oligopeptides, nucleotides and related compounds, quaternary ammonium bases, and guanidino compounds were analyzed to evaluate quality of anchovy sauce. The commercial products contained low proximate composition, extractive nitrogen and other extractive components, than the experimentally prepared anchovy sauce. Both samples, commercial products and experimentally prepared anchovy sauce, were rich in free amino acids, such as glutamic acid, leucine, alanine, lysine, and aspartic acid. The extractive nitrogenous components which consist of total nucleotides and related compounds, total free amino acids, methionine, isoleucine, valine, taurine, tyrosine, histidine, leucine, aspartic acid, cystine, and lysine, showed significant correlation(p<0.01) with extractive nitrogen. Possibly, seven kinds of free amino acids such as methionine, isoleucine, valine, taurine, tyrosine, histidine, and leucine, might be recommend as quality indices of standardization for anchovy sauce.

• Journal of the Korean Society of Food Science and Nutrition
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• v.13 no.2
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• pp.163-168
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• 1984

The composition of amino acids and the related compounds of nucleotides in the dorsal muscle of sweet fish Hemibarbus labeo, Mandarin fish Siniperca scherzeri and read fish Gobius similis was analyzed by amino acid autoanalyzer and high performance liquid chromatography. The result showed that IMP was dominant in the nucleotides of all the dorsal muscle of the fishes and a less amount of UMP, hypoxanthine and AMP was detected. In the free amino acid composition, the important amino acids were taurine and histidine in sweet fish, taurine, glycine and histidine in cornet fish, taurine, histidine and alanine in mandarin fish, taurine, proline and threonine in read fish, respectively, and in all the dorsal muscle of fishes, taurine was the dominant amino acid. In the amino acid compositions of the muscle protein, glutamic acid, glycine, aspartic acid and lysine were reached to 44.0% of total amino acids in sweet fish, glutamic acid, aspartic acid, lysine and glycine were 43.5% in cornet fish, glutamic acid, aspartic acid, lysine and leucine were 43.3%, 43.5% of total amino acids in mandarin fish and read fish, respectively. Glutamic acid was the dominant amino acid in all the fresh fishes.

• Applied Microscopy
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• v.23 no.2
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• pp.53-77
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• 1993

In this study, an attempt was made to investigate the probable organelles participating in the secretion of biligrafin. The animals (ICR male mice, 25-30gm) were divided into normal control and 6 biligrafin injected groups to which 30% biligrafin (0.006ml/gm b.w.) were injected at 10, 20, 40, 80, 160 and 320 min prior to the sampling. The mice of each group were perfused through the heart with ice-cold 2.5% glutaraldehyde buffered with 0.1M Na-cacodylate (pH. 7.4) under the Na-pentobarbital (Nembtal 0.0015mg/gm b.w.) anesthesia and liver tissues were taken from each group. Some specimens were immersed 1 hr in the same solution used in the perfusion. After an overnight rinse in 0.1M Na-cacodylate buffer containing 10% DMSO and 7.6% sucrose, $75{\mu}m$ fronzen sections were made for cytochemical study. The sections were incubated in thiamin pyrophosphatase (TPPase) and inosine diphosphatase (ID Pase) media for 70 min at $37^{\circ}C$ respectively and acid phosphatase (AcPase) medium for 40 min at $37^{\circ}C$. They were postfixed in 1 % $OsO_4$ for 1 hr. The other specimens were immersed for 8 hrs in the fixative consisting of 2.5% glutaraldehyde and 3.0% paraformaldehyde buffered with Na-cacodylate (pH. 7.4). All of the osmificated specimens were processed for electron microscopy. In both normal and biligrafin injected groups, endoplasmic reticulum (ER), vacuoles, Golgi apparatus and lysosomes were seen in the vicinity of bile canaliculus. In the biligrafin injected groups, however, the Golgi apparatus appeared to be decreased and ER and vacuoles were dilated and increased. The rough endoplasmic reticulum (RER) having a few attached ribosomes appeared to be the round saccule, especially at 20 min after biligrafin injection. Smooth endoplasmic reticulum (SER) seemed to be formed by the detachment of ribosomes at the cisternal end of RER. The cistern of SER showed saccules which probably budded off to form the vacuole. The vacuoles were devoid of visible centents. This finding seemed to be in agreement with the biochemical property of the bile constituents. The fusion between the vacuoles and bile canaliculus were frequently seen in the groups injected with biligrafin. The lysosome did not show any changes in the biligrafin injected groups. Accumulation of some material and lipid droplets were seen at the 40 and 80 min after biligrafin injection, especially at the latter. At 160 and 320 min after biligrafin injections, however, they were decreased successively while the RER stack, free ribosomes and polysomes were increased. Although the reactive products of TPPase and IDPase were observed in the ER saccules and vesicles of the normal control and biligrafin injected groups, the fusion between the bile canaliculus and saccules or vesicles could easily be seen in the latter. The AcPase activity, however, was observed in the cistern at the maturing face of Golgi apparatus and lysosomes in both normal and biligrafin groups. The results suggest that the biligrafin is excreted via the vesicles, vacuoles or sacoules probably derived from the SER without the participation of Golgi apparatus and lysosomes, and the excess amount of material is stored as inclusions during the repairing of the organelles being overactive.

• Korean Journal of Food Science and Technology
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• v.34 no.4
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• pp.666-672
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• 2002

Changes in chemical characteristic, microflora, and sensory evaluation of fish sauce extracted at an interval of one week from fermented solution were investigated. pH was reduced from 6.0 to 4.5, and trimethylamine oxide from 132.5 to 87.2 mg/100g during fermenting periods. Trimethylamine increased from 5.6 to 50.2 mg/100g, and volatile basic nitrogen from 48.3 to 232.5 mg/100g. Bacterial flora isolated from the fish sauce were 70% Lactobacillus sp. and 13% Bacillus sp. Among the free amino acids, alanine, glutamic acid, valine, and methionine contents constitute 40% of the total free amino acids. Major non-volatile organic acid of the fish sauce was lactic acid (76%). Sensory evaluation results of the fish sauce were higher than the traditional soybean sauce after 28 days of fermentation.

• Korean Journal of Food Science and Technology
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• v.34 no.6
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• pp.954-961
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• 2002

Extracts of raw bloody clams, broughton's ribbed ark (Scaphrca broughtonii), subcrenated ark (S. subcrenata), and granulated ark (Tegillarca granosa), were analyzed and compared foe extractive nitrogen, free amino acids, combined amino acids, ATP and related compounds, quaternary ammonium bases, and guanidino compounds. The contents of extractive nitrogen in broughton's ribbed ark, subcrenated ark, and granulated ark were 479, 506, and 432 mg/100 g, respectively. Twenty-eight or twenty-nine types of free amino acids were detected in all three extracts, among which taurine, ${\beta}-alanine$, glutamic acid, and alanine were the major ones. The composition of the major extractive components such as free amino acids, combined amino acids, ATP and related compounds, TMAO, TMA, and creatine in the extracts were similar among the extracts, but their contents were different.

• Animal Bioscience
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• v.34 no.7
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• pp.1193-1201
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• 2021

Objective: According to market demand, meat duck breeding mainly includes 2 breeding directions: lean Pekin duck (LPD) and fat Pekin duck (FPD). The aim of the present study was to compare carcass and meat quality traits between 2 strains, and to provide basic data for guidelines of processing and meat quality improvement. Methods: A total of 62 female Pekin ducks (32 LPDs and 30 FPDs) were slaughtered at the age of 42 days. The live body weight and carcass traits were measured and calculated. Physical properties of breast muscle were determined by texture analyzer and muscle fibers were measured by paraffin sections. The content of inosine monophosphate (IMP), intramuscular fat (IMF) and fatty acids composition were measured by high-performance liquid chromatography, Soxhlet extraction method and automated gas chromatography respectively. Results: The results showed that the bodyweight of LPDs was higher than that of FPDs. FPDs were significantly higher than LPDs in subcutaneous fat thickness, subcutaneous fat weight, subcutaneous fat percentage, abdominal fat percentage and abdominal fat shear force (p<0.01). LPDs were significantly higher than FPDs in breast muscle thickness, breast muscle weight, breast muscle rate and breast muscle shear force (p<0.01). The muscle fiber average area and fiber diameter of LPDs were significantly higher than those of FPDs (p<0.01). The muscle fiber density of LPDs was significantly lower than that of FPDs (p<0.01). The IMF of LPDs in the breast muscle was significantly higher than that in the FPDs (p<0.01). There was no significant difference between the 2 strains in IMP content (p>0.05). The polyunsaturated fatty acid content of LPDs was significantly higher than that of FPDs (p<0.01), and FPDs had higher saturated fatty acid and monounsaturated fatty acid levels (p<0.05). Conclusion: Long-term breeding work resulted in vast differences between the two strains Pekin ducks. This study provides a reference for differences between LPD and FPD that manifest as a result of long-term selection.

• Korean Journal of Food Science and Technology
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• v.54 no.1
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• pp.103-108
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• 2022

This study investigated the strains and fermentation characteristics of used to ferment a mixture of rice and soybeans to manufacture low-salt doenjang for flavoring. The soybean and rice mixture was fermented using three selected strains of Aapergillus oryzae and Bacillus sp. The changes in quality of the fermented products were found to be dependent on the aging period. Therefore, the strain and a suitable aging period were seleted based on the increases in AN, total sugar, and reducing sugar. The fermented products were prepared and mixed, using the selected or commercially available strains (the sample and control, respectively), to create low-salt doenjang. Following this, their characteristics were compared. The sample had a higher content of taste-related ingredients(free amino acid, nucleic acid-related substances) than the control. Using the selected strain to ferment a rice and soybean mixture will thus be expected to enhance the flavor of industrially produced seasoned doenjang.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.34 no.1
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• pp.7-12
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• 2001

To investigate difference of component changes in salt-fermented spring (SAS) and autumn (AAS) anchovy, Engraulis japonicus sauce during fermentation, various chemical properties were examined at $1.5\sim3$ months intervals during 18 months fermentation, The contents of total and amino nitrogen were higher in SAS than in AAS until 15.7 and 17.4 months fermentation, respectively, but there were no difference after that. The cross point of inosine (HxR) + hypoxanthine (Hx) and uric acid was faster in SAS with 10.6 months fermentation than in AAS with 11.5 months fermentation, After 18 months of fermentation, the SAS was rich in free amino acids, such as glutamic acid, alanine, aspartic acid, valine, lysine in that order, On the other hand, the AAS was rich in free amino acids, such as glutamic acid, leucine, alanine, lysine, isoleucine in that order. Absorbance at 453 nm were higher in SAS than in AAS, and increased gradually during fermentation.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.22 no.3
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• pp.154-160
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• 1989

To obtain basic data on food components of triploid fish, we undertook the analysis of free amino acid, nucleotide, total creatinine, betaine, trimethylamine oxide(TMAO) and their related compounds in diploid and triploid carps(Cyprinus carpio). The contents of total free amino acid and its related compounds in belly and dorsal muscles of triploid carp were 346.1mg/100g and 333.4mg/100g. Histidine occupied $45.1\%\;and\;46.9\%$ in belly and dorsal muscles, and followed by taurine, lysine and glycine in order. As for the compositions of nucleotide and its related compounds in those muscles of triploid carp, IMP were revealed $73.9\%\;and\;65.8\%$ of total nucleotide and its related compounds. The major component of the other organic base in those muscles of triploid carp was total creatinine, but betaine and TMAO were poor. The contents of taste compounds such as free amino acid, nucleotide, total creatinine, betaine, TMAO and their related compounds were less in triploid carp than in diploid carp of nonspawning season, while were more in triploid carp than in diploid carp of spawning season. Total amino acid contents were more in diploid carp of nonspawning season than in triploid carp, but mineral contents were more in triploid carp than in diploid carp of spawning season. Therefore, it is believed that triploid carp is very worthy for a tasty and nutritional food source.