• Journal of the Korean Society of Food Science and Nutrition
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• v.25 no.4
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• pp.665-671
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• 1996

Changes in the nutritional components of Toha-jeot, salt-fermented Toha shrimp(Caridina denticulata denticulata $D_{E} H_{AAN}$), which was salted with 20%(w/w) sodium chloride and fermented during 60 days at $4\pm1^{\circ}C$ were investigated. The free amino acid contents in Toha-jeot, of which glutamic acid, leucine, Iysine, arginine, glycine and alanine occupy the majority, in order of abundance, increased gradually up to 50 days of fermentation. Most of the nucleotides were decomposed to hypoxanthine; thus ATP and ADP were not detected. Fermentation decreased inosine, IMP and unsaturated fatty acid contents and increased saturated fatty acid contents of Toha-jeot. Palmitic acid was the most abundant fatty acid, followed by palmitoleic acid, linoleic acid, EPA and stearic acid. Among the mineral constituents of Toha-jeot, Na and Ca were dominantly occupying. The Hunter "L" and "b" values of Toha-jeot increased during fermentation while "a" value remained unchanged.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.15 no.2
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• pp.117-122
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• 1982

Abalone, Haliotis diversicolor japonica, is one of the most palatable sea foods in Jeju-Do, Korea : however relatively little is known about the characteristics of its taste. This study was undertaken to establish the basic data for evaluating the taste compounds in the extract of abalone including nucleotides and their related compounds, free amino acids, trimethylamine oxide, trimethylamine and total creatinine. The amount of AMP was $2.21{\mu}mole/g$ while IMP and inosine was trace in content. In the extracts, taurine, arginine and glycine were abundant holding $39.9\%,\;25.4\%,\;14.0\%$ of total free amino acids content respectively, but tyrosine and phenylalanine was trace in content. TMAO, TMA and total creatinine were poor in content marking $5.4mg\%,\;1.0mg\%\;and\;5.0mg\%$. It was presumed that the characteristic flavor of abalone was mainely attributed to free amino acids. Organic acids, nucleotides and their related compounds played auxiliary role in the characteristic flavor of abalone.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.50 no.5
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• pp.500-505
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• 2017

The nucleotides and their related compounds, including ATP (adenosine triphosphate), ADP (adenosine diphosphate), AMP (adenosine monophosphate), IMP (inosine monophosphate), HxR (inosine) and Hx (hypoxanthine), were nearly identical in oysters Crassostrea gigas from the two culture methods. The K-value was lower than the threshold value such as 11.2-12.1. Although oysters have low amount of IMP, it was detected in this experiment. DPPH radical scavenging activity did not vary significantly with sample amounts (100, 300, and $500{\mu}g/mL$). DPPH (1,1-diphenyl-2-picryl-hydrazyl) radical scavenging activity was 76.0-80.7% compare with the ascorbic acid standard. Superoxide anion scavenging activity reached 49.3% in the rack-and-bag culture sample at $500{\mu}g/mL$. However, the reducing power and $Fe^{2+}$ chelating activity were very low compared with their respective standard. The oyster culture methods did not affect oyster quality in terms of antioxidant activities.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.15 no.4
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• pp.303-311
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• 1982

Sensory evaluations of synthetic extracts prepared on the analytical data in the previous papers (Yang and Lee, 1979, 1930-a, 1980-b, 1982) were undertaken to determine the origin of the taste of wild common carp, Cyprinus carpio, and Korean snakehead: Channa argus. Taste panel assessments of synthetic extracts prepared with each extractive component omitted were carried out by a triangle difference test, and changes in taste profile were assessed. The synthetic extracts, prepared with about 40 pure chemicals based on the analytical data from the species satisfactorily revealed the natural taste of the original extracts except slight difference in meaty taste and mildness. From the results of omission test the major components which contribute to produce the taste of the species were assessed as follows: glycine, glutamic acid, arginine, lysine, threonine, alanine, IMP, inosine, hypoxanthine, glucose, succinic acid, $Na^{+},\;Cl^{-}\;and\;PO_{4}^{3-}$ in common carp: glycine, alanine, glutamic acid, IMP, Na+ and $PO_{4}^{3-}$ in Korean snakehead.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.22 no.5
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• pp.228-232
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• 1989

Katsuobushi has widely been used from olden times to prepare soup stock. This study was carried out to prepare stock of powdered Katsuobushi, and to examine the extractive conditions and the contribution of principal taste compounds to its characteristic taste. The extractive condition of powdered Katsuobushi in preparing stock was the most appropriate at $100^{\circ}C$ for 1 minute boiling water-steeping method in flavor, clearance of stock. From the chemical analysis and omission test, the principal taste-active components in $4\%$ solution powdered Katsuobushi under this extractive condition were nucleotides 93.6mg/100ml, free amino acids and imidazole dipeptides 41.3mg/100ml, and non-volatile organic acids 39.3mg/100l1 in order. IMP, inosine, AMP, histidine, anserine, taurine, carnosine and lactic acid were predominant among the detected compounds.

• Asian-Australasian Journal of Animal Sciences
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• v.31 no.1
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• pp.123-128
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• 2018

Objective: This study was performed to determine effects of different curing salts on the quality of salamis and to assess feasibility of using NaCl-alternative salts. Methods: Various types of curing salts (KCl or $MgCl_2$) as well as NaCl (sun-dried or refined) were incorporated for processing of salamis. The proximate composition, fatty acids, nucleotide-related compounds, and free amino acids of the salamis were analyzed during 40 days of ripening. Results: The substitution of NaCl by KCl caused higher fat and ash content, but lower moisture content of the salami after 20 days of ripening (p<0.05). Compared with the sun-dried NaCl, use of KCl in salami also led to greater inosine 5'-monophosphate whereas refined NaCl had more inosine (p<0.05). KCl-added salami also had a higher C12:0, C17:1, and C20:0 than other types of salami (p<0.05). $MgCl_2-added$ salami had higher content of free amino acids compared to the other salamis (p<0.05). Conclusion: Alternative curing salts such as KCl and $MgCl_2$ could substitute NaCl in consideration of quality factor of a fermented meat product. Especially replacement of NaCl with KCl will be a suitable strategy for developing relatively low sodium salami products without compromising product quality.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.45 no.6
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• pp.648-653
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• 2012

The present study examined the effects of dietary supplementation with nucleotide (inosine monophosphate product, IMP) on the growth performance, feed utilization, and non-specific immune responses of juvenile tilapia Oreochromis niloticus. Triplicate groups of tilapia (initial body weight, $7.4{\pm}0.04$ g) were fed experimental diets containing 0%, 0.05%, 0.1%, and 0.2% IMP. Fish were fed six times a day until apparent satiation for 13 weeks. At the end of the feeding trial, final body weight and food utilization of fish fed 0.1% IMP were significantly higher than those of fish fed the control diet. Results of hematological parameters were not affected by dietary IMP. However, blood protein level was significantly higher in the 0.05% treatment, as compared to that of the control and 0.2% IMP diets. Myeloperoxidase activity was higher in fish fed 0.1% IMP than in fish fed the control and 0.2% IMP diets. These results suggest that dietary supplementation with IMP can enhance the growth performance, feed utilization, and innate immune response of juvenile tilapia. The optimal IMP supplementation level appears to be 0.1% in practical feed formulations for tilapia.

• Korean Journal of Food Science and Technology
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• v.20 no.3
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• pp.385-391
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• 1988

In an attempt to develop natural seasoning materials by use of shellfishes and crustaceans, contents of taste components such as amino acids, nucleotide and its derivatives, the extractability of oyster (Crassostrea gigas), sea mussel(Mytilus coruscus) and crab(Portanus tribuerculata) were investigated. As a result of chemical analysis and sensory evaluation, the optimum condition of extraction could be concluded as extracting fresh or frozen raw materials for about 40 min. at $95^{\circ}C$ with 1.5 to 2 times of water by volume. The contents of free amino acids in the extractions were much in sequence as crab(1,886 mg%), mussel(765 mg%) and oyster(554 mg%), and the dominant amino acids in each extracts were identified as glutamic acid, alanine, glycine, proline and arginine in oyster, threonine, alanine, arginine, glycine and glutamic acid in mussel, arginine, proline, lysine, alanine and threonine in crab respectively. In addition, the major nucleotides affecting as taste enhancer of each extracts were estimated as inosine in oyster and crab, and inosine monophosphate in mussel respectively.

• Korean Journal of Food Science and Technology
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• v.5 no.4
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• pp.206-209
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• 1973

In this paper, the degradation of nucleotides and their related compounds in hag-fish muscle during roasting was studied. The results showed that IMP was dominant in fresh hag-fish showing 63% of total nucleotides while the contents of ATP, ADP, AMP, inosine and hypoxanthine were low. The ATP tended to degrade rapidly during roasting, but 80% of IMP remained and ATP, ADP and AMP were also entirely disappeared. In consideration of flavor quality, it was consumed that roasting is an effective preparation method of hag-fish, as far as IMP is concerned.

• The Korean Journal of Food And Nutrition
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• v.28 no.6
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• pp.1019-1025
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• 2015

The influence of aging on the flavor precursors and volatile compounds of top round beef was studied. The concentrations of free amino acids, nucleotides, creatine, dipeptides, and volatile compounds were measured after top round from Hanwoo was aged at $4^{\circ}C$ for 21 days. The amount of free amino acids in top round significantly increased with the increase of aging period. There was no effect of aging on the concentrations of adenosine monophosphate or inosine in top round. The inosine monophosphate content of top round significantly decreased with age, while the hypoxanthine content increased. The concentrations of creatine, carnosine, and anserine in top round were not influenced by aging. In total, 24 volatile compound were identified in aged, cooked top round. Of these, the quantities of aldehydes (propanal, pentanal, hexanal, heptanal, octanal, and nonanal), hydrocarbons (pentane and octane), 2-butanone, ethyl acetate, and pyridines (4-ethynyl-pyridine and 4-acetyl-pyridine) significantly increased after aging. We conclude that the flavor of top round can be improved by aging.