• The Korean Journal of Malacology
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• v.26 no.4
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• pp.267-273
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• 2010

From January to December 2007, we have investigated sediment types, environmental factors and density of clam Ruditapes philippinarum inhabited at Oeri, Naeri, Jonghyeon and Bangmiri tidal flats in Gyeonggi Bay off the west coast of Korea. Sediment types of Oeri and Jonghyeon were characterized with well sorted muddy sand. In contrast, Bangmiri tidal flat was mainly composed of poorly sorted gravelly muddy silt and Naeri was characterized with very poorly sorted muddy-sandy gravel. During the course of study, the surface water temperature, salinity, dissolved oxygen and pH ranged 3.2 to $27.0^{\circ}C$, 21.7 to 33.3 ‰, 5.6 to 12.7 mg/l and 7.36 to 8.82, respectively. The suspended solid (SS) ranged from 3.2 to 1,266.0 mg/l and chlorophyll-a level in the water column ranged $0.3-36.1{\mu}g/l$, respectively. The density of clam in the study areas was mainly determined by the harvesting activities rather than the types of substrate. Relatively higher density of clam was observed in Oeri and Bangmiri where the clam seeds were sowed by the villagers. Condition factor of clams were found to be higher in Oeri where the substrate sorting was better with higher level of chlorophyll a. It was believed that sediment types and the level of available food the two governing factors controlling the density and growth of clam in Gyeonggi Bay.

• Korean Journal of Food Science and Technology
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• v.28 no.5
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• pp.882-887
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• 1996

Some taste compounds such as nucleotide and their related compounds, trimethylamine oxide (TMAO), trimethylamine (TMA) and total creatinine of sea mussel and baby clam during drying at 40, 50 and 60^{\circ}C$ and storage at low temperature$(4^{\circ}C)$ and room temperature$(20^{\circ}C)$ were investigated. Six kinds of nucleotide and their related compounds such as adenine triphosphate (ATP), adenine diphosphate (ADP), adenine monophosphate (AMP), inosine, adenosine and hypoxanthine were analyzed. The contents od adenosine in raw sample was high in sea mussel and baby clam. The contents of ATP, ADP and AMP decreased, while those of inosine and hypoxanthine increased during drying and storage periods. The contents of TMAO, TMA and total creatinine were low in sea mussel and baby clam. TMAO and total creatinine decreased but TMA increased during drying and storage periods. The rate of change was high in room temperature storage and for long storage periods than that of low temperature storage and for short storage periods.

• Journal of the Korean Society of Food Science and Nutrition
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• v.25 no.5
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• pp.774-778
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• 1996

The changes in organic acid contents of sea mussel and baby clam during drying at 40, 50 and $60^{\circ}C$ and storage at low $temperature(4^{\circ}C)$ and room $temperature(20^{\circ}C)$ were investigated. Organic acids of 8 varieties were determined and the content of succinic acid occupied over 90% of total organic acids in sea mussel(410.9mg%) and baby clam(96.5mg%). Malic acid was in order in sea mussel(41.2mg%) and lactic acid was in order in baby clam(61.9mg%). The content of organic acids was decreased during drying and rate of decreasing was higher at low drying temperature(40 and $50^{\circ}C)$ than that of high drying $temperature(60^{\circ}C).$ The decreasing rate was higher at room $temperature(20^{\circ}C)$ storage and long storage periods than that of low $temperature(4^{\circ}C)$ storage and short storage periods.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.3 no.3
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• pp.161-171
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• 1970

1. The higher the temperature of the sea water, and the smaller the size of the oriental brown shrimp, the higher the feeding rate of the shrimp will be as long as the temperature ranges from $19^{\circ}\;to\;30^{\circ}C$, and each shrimp weighs from 1.6 to 14.9 grams. The average daily feeding rate is between 18 to 44 percent. 2. The nighttime feeding rate is always higher than the daytime feeding rate. However, the daytime feeding rate can be raised to from 22 to 37 percent of the daily feeding rate iii the non-sediment, dark or direct-sunshine-shielded conditions. Growth can thus be accelerated to that extent under such conditions. 3. When anchovy and short-necked clam meats were simultaneously used as food, a greater quantity of anchovy meat was consumed than short-necked clam meat both during the daytime and nighttime. When anchovy and short-necked clam meats were simultaneously given, the averaged daily feeding rates of anchovy and short-necked clam meats were 12.9 percent and 10.3 percent, respectively. 4. The following equation applies to the relationship between the freight of the oriental brown shrimp (W in grams) and their daily growth rate (DGR in percent): log DGR=0.7035-0.7864 log W. The daily growth rate is in inverse proportion to the size of the shrimp. 5. The efficiency of food conversion of the oriental brown shrimp fluctuates between 2.8 and 7.8 percent without extensive difference depending on the size of the shrimp. This was very small as compared with the corresponding figures so far known for fish and cuttlefish.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.32 no.5
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• pp.659-663
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• 1999

Gametogenesis, reproductive cycle, condition factor, and meat weight rate of the surf clam, Tresus Keenae were studied by histological observations and morphometric data based on the samples which have been collected from the south coast of Korea, from January 1995 to February 1996. The annual ranges of the mean seawater temperature and specific gravity in habitat of the surf clam were $4.9\~24.9^{\circ}C$ and 1.0210$\~$1.0266, respectively. Monthly changes in the condition factor showed in a wide range from 0.2381 to 0.2827, began to increase in January and reached the first maximum (0.2827) in April. And then the value rapidly decreased in June, thereafter, reached the second peak (0.2812) in August. The condition factor of this species showed the two peaks, and gonadal development reached sexually mature and ripe conditions during the period of these two peaks. The meat weight rate ranged from $38.0\%$ to $46.4\%$, and its change showed a similar tendency with the condition factor. The reproductive cycle of this species can be divided into five successive stages: in both sex, multiplicative (December to January, July to August), growing (January to February, September to October), mature (February to April, September to November), spawning (April to June, September to November), and degenerative and resting stage (May to July, November to January).

• Korean Journal of Fisheries and Aquatic Sciences
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• v.8 no.1
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• pp.20-30
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• 1975

It is matter of fact processing technology must affects the quality and yield of final product and these also depend on the selection of raw material directly or indirectly. So that the estimation of tile preprocessing condition of shellfish is of great importance for distributors and processors. This study was attempted to establish the basic data for evaluating the processing suitability of baby clam, which is one of the five important shellfishes for domestic use and export. The important results are as follows: 1. The ratio of meat volume and meat weight to the holding capacity by shells may be useful for measuring the condition index of baby clams. 2. Baby clams grown in the beds with the composition of a large quantity of gravel were low in condition index value than in sand and mud. 3. If the green feed phenomenon was the prime consideration for canned baby clams, tile most suitable harvest season if October. In this period, the digestive tract in body was almost colorless. 4. As a whole, seasonal changes of moisture and fat content in baby clams were reversely correlated. Protein content increased from April and slightly decreased for a while from July to August and increased again from September. In March, the content of glycogen was 6.3 to 6.8 percent. From this period to October, glycogen was rapidly decreased. In October, it was only 0.1 to 0.2 percent but increased from November. There were little seasonal changes in pH value and crude ash content. The pH value of meat was 6.0 to 6.2 and crude ash content was about 2 percent. 5. By the results of condition index and chemical composition of baby clams, the suitable harvest season as raw materials for processing was from March to June and from September to October. 6. The steamed baby clam meat was packed with 2 percent salt solution containing 0.15 percent, citric acid or 0.5 percent $Na_2$ EDTA in a round sanitary tin can coated with C-enamel that is 203.9 ml by volume and sterilized for 60 minutes at $112^{\circ}C$. The canned product has shown a good result to reserve the natural characteristics of baby clam through six month storage at room temperature.

• Korean Journal of Food Science and Technology
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• v.8 no.3
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• pp.147-160
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• 1976

Pacific oyster, hard clam and mussel were irradiated at doses up to 0.5 Mrad, the optimum dose rather than the maximum permissible was sought for in each species and post-irradiation storage characteristics studied at $0^{\circ}\;and\;5^{\circ}C$. No shellfish meat irradited at doses as high as 0.5 Mrad produced any adverse odor. However the organoleptic quality of each sample irradiated at lower doses was superior to those irradiated at the higher during the early storage period. The optimum dose was determined to be 0.2 Mrad for Pacific oyster and mussel and 0.1 Mrad for hard clam. By irradiating at the optimum dose, the storage life of Pacific oyster cculd be extend from less than 14 days to 35 days at $0^{\circ}C$ and from only 3 days to 21 days at $5^{\circ}C$. A similar storage extension was observed with mussel. The storage life of hard clam was extended from 7 days to 14 days at $0^{\circ}C$ and from 3 days to 12 days at $5^{\circ}C$. The hard clam meats were particularly susceptible to tissue softening by irradiation; an earlier onset and more extensive softening were observed with increasing dose.

• The Korean Journal of Ecology
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• v.1 no.2
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• pp.49-56
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• 1977

For the culture the population growth, shell length and spawning seasons of Gomphina veneriformis, and its environmental factors, were investigated at the Jeju coastal regions. from Feburuary, 1975 to March, 1976. The soil movements of the tidal flats where the clams inhabited were relatively rapid during the strong tidal actions. The rate of population growth were rapid from April to September, then became obsure. The relative growth equations of the shell height (SH) and the shell breadth (SB) against the shell length (SL) of the clams were as follows: Changhung : SH=0.751 SL + 0.685, SB=0.448 SL-0.630 Pyoson : SH-0.775 SL - 0.115, SB=0.464 SL-1.008 Hwhason : SH=0.794 SL - 0.923, SB=0.485 SL-1.155 Kwhagzee : SH=0.771 SL - 0.644, SB=0.455 SL-1.049 The meat weight increases of the clams were continued from March to late June, then it decreased sharply up to late August. The spawning of the clams seems to be late from June to Spetember in the regions studied.

• Journal of the Korean Society of Food Science and Nutrition
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• v.28 no.1
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• pp.16-21
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• 1999

Taurine content was determined by HPLC equipped with RF detector in commercial milks, meats, edible viscera, ham, sausage, fishes and shellfishes, mollusca and crustacea. Taurine contained 1.06~1.57mg/100g in milks, 37.9~169.8mg/100g in lean meats, 11.3~192.4mg/100g in viscera, 45.0~109.1 mg/100g in ham, 11.7~26.0mg/100g in sausage, 31.6~431.9mg/100g in fishes, 125.9~1078.8mg/100g in shellfishes, 340.2~ 1305.6mg/100g in mollusca and 79.3~316.5mg/100g in crustacea. Webfoot octopus had the highest content of 1,306mg/100g, followed by small ark shell(1,079mg/100g), little neck clam (868mg/100g), hard shelled mussel(852mg/100g) and beka squid(734mg/100g).

• The Journal of the Convergence on Culture Technology
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• v.2 no.4
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• pp.1-21
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• 2016

This article examined the different types of Jeonuhwa as recorded in 16 royal palace studies from the Joseon dynasty (1392-1909). The ingredients used in Jeonuhwa during the Joseon dynasty were categorized as follows: 16.0% for gray mullet(秀魚) and fish(生鮮), 14.2% each for liver and cow stomach, 12.3% for sea cucumber(海蔘), 4.7% each for crab(蟹), clam(生蛤), and chunyup(千葉), 3.9% each for pork meat(豬肉), octopus, 2.8% each for oyster(石花), pheasant(生雉), and chicken(鷄), 2.0% each for croaker(民魚), and brain (骨), 0.9% each for duck(鴨子), pigeon(山鳩), dobi(都飛), snapper, white fish(白魚), mussel(紅蛤), haeran(蟹卵), quail(鶉鳥), egg(鷄卵), and sesame(實荏子). This observation may be associated with commercial industrial development that prevailed during the late Joseon dynasty. Further studies will be conducted on recipes and ingredients recorded in Euigwe in order to develop a standardized recipe for Jeonuhwa.