• Food Science and Preservation
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• v.17 no.4
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• pp.533-540
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• 2010

Overall composition, and fatty acid, amino acid, and nucleotide-type compound levels in wild (Haliotis gigantea) and cultured abalone (Haliotis discus hannai), were investigated. Wild abalone had a higher moisture content than did cultured abalone, but the converse was true for crude protein content. In overall composition, crude lipid level was higher in the viscera than in the meat, with the greatest level, $2.02{\pm}0.15%$ (w/w), observed in the viscera of wild abalone. The major fatty acids were palmitic acid (16:0), oleic acid (18:1n-9), eicosatrienoic acid (20:3n-3, ETA), eicosapentaenoic acid (20:5n-3, EPA), and docosahexaenoic acid (22:6n-3, DHA). The omega-3 fatty acid content (EPA and DHA) was higher in wild than in cultured abalone. A total of 17 amino acids were detected in all abalone samples, most of which had high levels of aspartic acid, glutamic acid, glycine, and arginine, and low amounts of cysteine, methionine, and histidine. Glutamic acid was the most abundant of all amino acids. The content of free amino acids was related to taste score. The major free amino acids were taurine, alanine, and arginine, of which taurine was the most abundant, and was present at higher levels in wild compared to cultured abalone. The total contents of nucleotide-related compounds in wild and cultured abalone were 12.93 mg/100g and 30.75 mg/100g, respectively.

• Journal of Korean Society of Environmental Engineers
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• v.32 no.5
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• pp.469-476
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• 2010

The purpose of the study is to find ways to decrease turbidity and residual aluminum by improving the efficiency of coagulation process through controlling the pH of the source water with $CO_2$ when the pH increases by algal bloom or by the characteristics of the source water. Water quality parameters were monitored before and after $CO_2$ addition in February, March, April, and December, when the pH of the source water is over 8.0 and constant regardless of day and night. Water quality parameters closely related with evaluation of treated drinking water quality were monitored in detail, e.g. aluminum, turbidity, particle counts, TOC, THMs, 2-MIB, and geosmin. According to the results, inorganic water quality parameters such as turbidity, particle counts, and aluminum were decreased due to improved efficiency of the coagulation process. It was concluded that the pH of the water in the arrival basin must be controlled below 7.4 by adding $CO_2$ when the pH of the source water increasing. By controlling pH with $CO_2$, the water quality could be maintained within the drinking water quality goal of Seoul City (<30 particle/mL of particle count, <0.05 NTU of turbidity and <0.02 mg/L of aluminum). The change of the pH could not affect the concentrations of DBP's (e.g., THMs, CH, and HAAs) and taste/odor causing compounds (e.g., 2-MIB and geosmin). 2-MIB and geosmin were affected more by their initial concentrations in the source water.

• Korean Journal of Food Science and Technology
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• v.22 no.2
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• pp.221-226
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• 1990

Fish flesh of Alaska pollack containing 5% of corn starch were fermented with 8 strains of mold and monitoring of their flavor characteristics, acceptability, nucleotides and their related compounds, amino acid compositions were conducted. All strains were grown vigorously on fish flesh media and formed their characteristic spores with unique flavor by strains. Amino type nitrogen $(NH_2-N)$ content of fermented fish flesh (FFF) were 25-26 times higher than that of raw flesh and 6-15 times higher in extractable nitrogen (Ex-N) content . The strains which produce more ADP (Adenosine 5'-diphosphate) in FFF also showed much higher level of IMP (Inosine 5'-monophosphate) and GMP (Guanosine 5'-monophosphate) content than that of raw flesh. Amino acid composition were differ by strain but lysine was generally highest and arginine, glutamic acid, leucine and alanine in order In review of sensory evaluation , total content of nucleotides, $NH_2-N$, Ex-N and amino acid compositions, suitable strains for fish flesh fermentation were Aspergillus oryzae KFCC 11371, Asp. oryzae KFCC 32343, Penicillium roqueforti KFCC 11269 and Asp. quercinus.

• Food Science and Preservation
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• v.18 no.5
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• pp.746-754
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• 2011

This study analyzed the taste components of dorsal muscle and fin muscle collected from olive flounder cultured with extruded pellet (EP) compared with those of olive flounder cultured with raw fish moist pellet (MP) as a control. The olive flounder in this study were cultured for 10 months with either the formulated extrude pellets (FEP), commercial extruded pellets (CEP) or the MP feed, and the average weight was 1.15 kg. The major nucleotides and related compounds in the dorsal muscles of the fish fed with MP, CEP and FEP diets were AMP and IMP. The fin muscle of the olive flounder contained the largest amounts of IMP($5.91{\mu}mol/g$). The K value of the dorsal muscle in olive flounder fed with MP, CEP and FEP showed 9.63%, 9.83% and 5.84%, respectively. The free amino acids in the dorsal muscle of olive flounder showed significantly differences in the composition depending on the feed, but the distribution of free amino acids showed similar patterns. Among free amino acids, taurine showed the highest content in all the experimental groups, and the asparagine and citrulline contents were significantly higher in the groups fed with CEP and FEP than in the group fed with MP. The significant differences were observed in the contents of specific free amino acids in dorsal muscle and fin flesh depending on the feed for cultured olive flounder.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.53 no.6
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• pp.823-833
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• 2020

The Manila clam Ruditapes philippinarum, is an important marine bivalve that is widely distributed along the west and north coasts of South Korea. It has been used in a variety of Korean foods owing to its superior umami taste. In the present study, we developed a flavoring with an excellent sensory preference from Manila clam using extrusion cooking processing. Optimization of extrusion cooking conditions was performed using response surface methodology (RSM). Barrel temperature (X1, 140-160℃) and screw speed (X2, 400-560 rpm) of the extruder were chosen as independent variables. The dependent variable was overall acceptance (Y, points). The estimated optimal conditions were as follows: overall acceptance (Y): X1=140℃ and X2=560 rpm. The indicated value of the dependent variable overall acceptance (Y) under the optimal conditions was 8.94 points, which was similar to the experimental value (8.82 points). Overall acceptance of the Manila clam flavoring was related to its umami and Manila clam tastes. The electronic nose and tongue results successfully segregated different clusters of the samples between the lowest and highest sensory scores. The sample with the highest sensory score had higher sourness, umami, and sweetness intensities, and the lowest sensory scored sample showed more off-flavor compounds.

• Journal of the Korean Society of Food Science and Nutrition
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• v.33 no.8
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• pp.1398-1406
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• 2004

To develop the new type of salt-fermented seafoods, the salt-fermented oysters in olive oil (product SO) were manufactured, and food components and quality characteristics of product SO were examined. The optimum processing condition for product SO is as follows. The raw oyster with no shell was washed off with 3% saline solution. Then dewatered, and dipped in the brine-salting solution made up with saturated saline solution and oyster sauce (2 : 1 v/v) mixture added 1% sodium erythorbic acid and 0.2% polyphosphate. After salt-fermentation it ripened by brine salting at 5$\pm$1$^{\circ}C$ for 15 days. Then dried at 15$^{\circ}C$ for 4 hours with cool-air, and packed in No. 3B hexahedron type can. Finally, poured with olive oil and seamed it by double-seamer. The moisture, crude protein, crude ash and volatile basic nitrogen contents of the product SO were 61.6%, 12.0%, 16.3% and 34.3 mg/100 g, respectively. In taste-active components of the product SO, total amount of free amino acids is 2,335.4 mg/100 g and it has increased by 50% overall during salt-fermentation 15 day. Taurine, glutamic acid, proline, glycine, alanine, $\beta$-alanine and lysine were detected as principal free amino acids. The contents of inorganic ions were rich in Na and K ion, while the amounts of nucleotide and its related compounds and other bases except betaine were small. From the results of this research, the product SO had a superior organoleptic qualities compared with conventional oyster product, and could be reserved in good conditions for storage 90 days at room temperature.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.26 no.3
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• pp.221-229
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• 1993

In this study fermentation of fresh ascidian was attempted to widen the utility of ascidian. Fresh deshelled and sliced ascidians were fermented for 90days at $25^{\circ}C$ with different salt contents of 5, 10, 15 and $20\%$ (w/w) and at $5^{\circ}C$ with 5 and $10\%$ salt. Changes of such components during fermentation as free amino acids, nucleotides and the related compounds, volatile basic nitrogen(VBN), trimethyl amine(TMA), amino nitrogen and total creatinine were determined. VBN increased rapidly after 30days of fermentation at $25^{\circ}C$ while slowly in cases of fermentation at $5^{\circ}C$ and with high salt concentration. Amino nitrogen and the total creatinine also increased gradually until 45 days and 30days of fermentation, respectively, hereafter tended to decrease. ATP and ADP seemed to degrade rapidly in fresh ascidian post harvest and AMP, IMP and inosine also degraded down to hypoxanthine during fermentation. After 45days of fermentation, in the free amino acid composition of fermented ascidian were taurine, proline, glutamic acid, histidine, lysine, alanine and valine in order. The amino acids known as sweetner like prolline, lysine, alanine and glycine were in increased in fermented ascidian. The result of sensory evaluation of fermented ascidian pretreated with acid or sulfite solution showed that the peculiar taste and flavor of ascidian remained without browning for 45days fermentation at $5^{\circ}C$.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.32 no.1
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• pp.75-82
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• 1999

The hydrolysate of desalinated tuna boiled extract (TBE) were prepared by continuous hydrolysis of TBE using a membrane reactor. TBE and tuna boiled extract hydrolysate (TBEH) were isolated depending on molecular weights. The major molecular weight distributions of TBEH-l0K, TBEH-5K and TBEH-lK were 9,800Da, 3,000Da and 990Da, respectively. The amounts of nucleotides and their related compounds of TBE were 3.47 $\mu$mole/g AMP, 23.75 $\mu$mole/g IMP, 9.07 $\mu$mole/g inosine and 1.89 $\mu$mole/g hypoxanthine. Total content of amino acids having desirable taste (glycine, glutamic acid, alanine, proline, aspartic acid, serine) was about $63\%$ of total amino acid from TBE and about $62\%$ from TBEH. The natural seasoninings were prepared with TBE and TBEH. From the results of sensory evaluations, complex seasoning containing TBEH-1K was almost equal to the shellfish complex seasoning obtained from the market. The mixed sauce which was made by mixing of $50\%$ TBEH sauce and $50\%$ fermented soy sauce was similar to the tradition soybean sauce in product quality and it showed the possibility to be used for the substitute product for acid hydrolyzed soysauce.

• Korean Journal of Food Science and Technology
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• v.29 no.5
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• pp.955-962
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• 1997

The food components of three kinds of edible ascidians being cultivated and caught in Tongyeong and Jisepo districts, Kyongnam of Korea were investigated. Wild Halocynthia roretzi (WM) and Pyura michaelseni (DM) were higher in contents of moisture and crude protein than cultured Halocynthia roretzi (CM). Total combined amino acid contents of CM, WM and DM muscles were 11,425.4 mg%, 11,595.4 mg% and 12,152.7 mg%, respectively, and major amino acids were Asp, Glu and Lys. The major fatty acids were 14:0, 16:0, 16:1n7, 18:1n7, 18:4n3, 20:5n3 and 22:6n3, and composition ratio of n3 polyunsaturated fatty acids of CM, WM and DM were 39.1%, 47.0% and 46.5%, respectively. In extracts components, total free amino acid contents of CM, WM and DM were 1,071.3 mg%, 1,278.7 mg% and 1,133.2 mg%, respectively, and the major amino acids were Tau, Glu, Pro, Asn, Gly, and Ala, while Arg was contained little quantities. As for nucleotides and related compounds, AMP was the principal component and IMP was detected though very small amounts in ascidian samples. Also contents of TMAO, total creatinine, betaine and peptide-N were $12.2{\sim}18.1\;mg%,\;15.5{\sim}19.6\;mg%,\;270.5{\sim}329.9\;mg%\;and\;62.0{\sim}111.0\;mg%,$ respectively. In inorganic ions of ascidian samples, the major components were $Na^+,\;K^+,\;Cl^-\;and\;PO^{3-}_4$.