• Korean Journal of Fisheries and Aquatic Sciences
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• v.55 no.5
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• pp.714-720
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• 2022

A dietary comparison of yellow goosefish Lophius litulon in the South Sea and Yellow Sea was performed by analyzing stomach contents. Using a bottom trawl net from fisheries resources survey vessels of the National Institute of Fisheries Science, 326 individuals were collected from the South Sea and 166 individuals were collected from the Yellow Sea. The total length range of L. litulon was 5.3-68.4 cm for individuals collected from the South Sea and 7.5-55.1 cm for individuals collected from the Yellow Sea. Based on the index of relative importance and the variation in stomach contents by fish size, L. litulon was found to be a piscevore and a spatiotemporally opportunistic feeder fish that fed mainly on pisces. There were differences in the composition of the stomach contents by season, location, and the interaction between the season and the location. Thus, the diet of L. litulon is affected by the prey abundance and prey spectrum of the habitat.

• Korean Journal of Ichthyology
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• v.35 no.2
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• pp.129-135
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• 2023

The diet composition of skinnycheek lanternfish, Benthosema pterotum were collected by bottom trawl net in the South Sea of Korea during 2021 (February, May, August, and November) and 2022 (February, April, August, and November). The size of the specimens ranged from 16 to 73 mm in total length. B. pterotum were mesopelagic carnivores that mainly consumed euphausiids and copepods. Its diets included small quantities of amphipods, shrimps, mysids, etc. We calculated the trophic level as 3.16 for B. pterotum. The individuals of small size class (<40 mm) fed mainly on copepods. In the next size classes (40~45 mm, 45~50 mm, 50~55 mm), copepods' proportion decreased and euphausiids increased. In the largest class (55~60 mm and ≥60 mm), the proportion of euphausiids' decreased, and shrimps increased. As the body size of B. pterotum increased the mean weight of prey per stomach (mW/ST) tended to significantly increase (One-way ANOVA, P<0.05).

• Korean Journal of Ichthyology
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• v.34 no.3
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• pp.201-207
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• 2022

Total 418 Yellow Croaker Larimichthys polyactis were examined and the range of total length (TL) was 12.0~27.5 cm and average total length was 19.6 cm. The most important prey component in the diets of L. polyactis was Pisces that constituted 46.5% in %IRI (Index of relative importance). Euphausiacea was the second largest prey component. The result of analysis in ontogenetic and seasonal changes significantly exhibited. The proportion of Pisces increased as increasing body size, whereas the consumption of Macrura decreased gradually. The diets also were different among seasons, with the difference particularly being evident between warm (summer and autumn) and cold (winter and spring) seasons. Permutational multivariate analysis of variance (PERMANOVA) revealed significant dietary differences by seasons (P=0.001).

• Korean Journal of Ichthyology
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• v.35 no.4
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• pp.305-312
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• 2023

Diet composition and feeding strategy of the largehead hairtail, Trichiurus japonicas were studied using 375 specimens collected by purse seine, set net fisheries and lure fishing from February 2021 to January 2022 in the southern sea of Korea. The anal length (AL) of these specimens was from 3.4~49.0 cm. T. japonicus fed majorly on Fishes (especially Engraulis japonicus) based on ranking index (%RI=99.3). Fishes were the main prey items for all size classes. T. japonicas also showed size-related dietary shift from E. japonicus to T. japonicus, Larimichthys polyactis and Engraulidae. Fishes were the main prey items for all seasons. The main fish prey during spring and summer was E. japonicus, but in the autumn and winter, the E. japonicus portion decreased, and T. japonicus, L. polyactis, and Engraulidae portion increased. T. japonicus were specialized feeders with E. japonicus as their dominant prey.

• Korean Journal of Environmental Biology
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• v.35 no.4
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• pp.677-683
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• 2017

The Korean aquaculture industry was generally began in the 1970s and has gradually increased. Now, the number of households is about 7,068 and the scale of an aquaculture farm is about 248,014 ha; the value of all production in the industry is estimated to be about 1602.2 billion won. The aquaculture industry is very valuable and important for future food resources. However, the aquaculture industry was damaged by several marine ecological disturbance causing organisms. The Ascdiella aspersa colonized on the shell of scallop and then scallops were detached from rope. The patterns of damage in the aquacultures were observed in Tongyeong (oyster), Geojedo (oyster), and Gangneung (sea squirt) in June, 2017, as well as in Tongyeong (oyster) in November, 2017 by SCUBA divers. The species Halichondria bowerbanki, Bugula neritina, Mytilus galloprovincialis, Balanus amphitrite, Ascidiella aspersa, Ciona intestinalis, Didemnum sp, Styela plicata in Tongyeong, M. galloprovincialis, A. aspersa, C. intestinalis, D. vexillum, S. plicata in Geojedo, and M. galloprovincialis in Gangneung were all usually found in their farms. The marine ecological disturbance causing organisms gave rise to a reduced number of aquaculture products.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.48 no.4
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• pp.411-416
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• 2015

Olive flounder Paralichthys olivaceus production has increased gradually in recent years, but prices have fallen. Thus, the development of a variety of processed foods incorporating olive flounder would help to increase the income of fishermen. This study was conducted to investigate the best method for olive flounder ball processing. Clean olive flounder were divided into five portions. Olive flounder meat (100 g with added egg white 39 g) was chopped and then mixed with 10 mL fresh cream and ingredients. The dough was molded into the shape of a ball. The olive flounder balls were then processed by two different methods. In the first method, the flounder ball was boiled in water for 3 min then vacuum-packed in polyethylene film and stored at $-20^{\circ}C$ for 7 days. After 7 days, the ball was thawed and heated in a microwave for 2 min (Sample-1). In the second method, the ball was vacuum-packed in polyethylene film without boiling and then stored at $-20^{\circ}C$ for 7 days before thawing and boiling in water for 3 min (Sample-2). After heating, both types of olive flounder balls were evaluated. Various factors (including the viable bacterial count, chemical composition, pH, hardness, thiobarbituric acid level, salinity, and free amino acid content) were measured, and a sensory evaluation was conducted. Based on the results of the sensory and hardness evaluations, Sample-1 was deemed to be superior to Sample-2.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.49 no.3
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• pp.293-300
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• 2016

In the present study, we investigated the quality, sensory characteristics and commercialization potential of a rice collet snack made with the addition of dried shrimp. “Mild” and “spicy” snack products were produced with an edible oil coating and mixed seasoning powder coating, respectively. The approximate composition of the mild and spicy snacks, respectively, were 2.44% and 2.24% for moisture, 8.52% and 8.64% for crude protein, 18.36% and 26.54% for crude lipids, 1.28% and 1.38% for ash, 1.1% and 1.2% for salt, and 0.61 and 0.62 for pH. The L (lightness), a (redness), b (yellowness), and ⊿E (color difference) values were higher for the mild snack than the spicy snack. The mild and spicy snack had values of 7,776.4 and 7,655.8 mg/100 g for total amino acids, and 221.6 and 253.5 mg/100 g for total free amino acids, respectively. The TBA (thiobarbituric acid) value did not differ significantly between the two types of snack. The hardness value of the spicy snack was higher than that of the mild snack, but there were no significant differences in flavor between the two products. The sensory evaluation score of the spicy snack was slightly higher than that of the mild snack. Organoleptic inspection indicated that both snacks had a favorable, unique taste.

• Journal of Fisheries and Marine Sciences Education
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• v.28 no.3
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• pp.713-726
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• 2016

This study were attempted to apply the HACCP system adopted in the dried anchovy workplace to ensure the hygiene safety of dried anchovy workplace. In this study, HACCP system procedures, including HACCP team organization, determination of critical control point(CCP), establishment of critical limits, mornitering and verification etc., were established using KFDA 12 procedures. To determine whether hazards were critical elements, we evaluated the likelihood and seriousness of each hazard element. The likelihood of residual microorganism and metal piece exceeding the acceptable limit in dried anchovy products were demonstrated to be a critical hazard element. Management of the boiling(CCP-1B) and metal detection(CCP-2P) were determined to be a critical control point. The standards for acceptable residual microorganism and metal piece were set based on relevant laws and regulations, and then the limits were adapted and established for the CCP. An HACCP plan applicable to dried anchovy workplace was established.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.56 no.6
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• pp.759-765
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• 2023

Owing to the increase in the elderly population at aquaculture farm and decrease in the number of aquaculture farmers, the need to improve aquaculture production system is increasing. In addition, asvirtual interactions become new normal after COVID-19 pandemic, the speed at which science and technology such as the internet of things (IoT), information and communications technology (ICT), and artificial intelligence (AI) are applied to each field is accelerating. Efforts are being made to enhance the quality of life of aquaculture farmer and competitiveness of the aquaculture industry by incorporating digital technology. This study analyzed national and global aquaculture technology development and policy trends, smart aquaculture terminology application scenarios, and prior research cases to propose smart aquaculture industrialization models and technology development directions considering technology, economy, and environment. This study can also provide valuable reference for promoting smart and efficient development of aquaculture.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.53 no.4
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• pp.530-537
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• 2020

This study compared the survival rates, growth, and fatty acid content of larval Pacific cod Gadus macrocephalus fed with rotifers raised on different enrichment diets. We used four commercial rotifer enrichment products (one domestic, ER1, and three imported, ER2, ER3 and ER4). Twelve 200-L tanks were used, with three replicates per treatment. Larvae were fed rotifers 3 times daily at a rate of 5 rotifers/ml/feeding from 7 to 21 days post-hatch. At the end of the feeding trial, the survival rate and total length of larvae fed ER3 were greater than those of larvae fed ER1, ER2, or ER4. ER3 had the highest proportions of eicosapentaenoic acid (EPA), docosahexaenoic acid (DHA), and polyunsaturated acid (PUFA). Partially reflecting this composition, larvae fed ER3 had the highest proportions of DHA and PUFA. These results show a positive effect of rotifer DHA and PUFA proportions on the survival and growth rates of Pacific cod larvae.