• Korean Journal of Fisheries and Aquatic Sciences
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• v.50 no.1
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• pp.92-97
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• 2017

The feeding habits of larval Engraulis japonicas (3.2-11.0 mm SL) were examined based on 414 individuals, collected in October 2010, and from June to September 2011, in the coastal waters of Eastern Jinhae Bay, Korea. E. japonicus, fed mainly on copepods 62.6% IRI and tintinnid were the second-largest dietary component. E. japonicus diet also included small quantities of rotifers, eggs and diatoms. The results of analysis of ontogenetic changes showed that E. japonicus of small size classes (${\leq}4mm$) fed primarily on tintinnids. The dietary percentage of copepods decreased, as fish size increased, and monogeneans became increasingly important as size class increased above 4-6 mm. The highest rate of daily feeding E. japonicusi took place during the day.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.55 no.4
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• pp.320-326
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• 2019

The diet composition of Arctoscopus japonicus was studied using 448 specimens collected in the coastal waters of East Sea, Korea. The size of the specimens ranged from 6.2-25.3 cm in total length (TL). A. japonicus were fed mainly on amphipods that constituted 76.1% in IRI. Euphausiids were the second largest prey component. The diets also include small quantities of crabs, copepods, mysids, cephalopods, monogeneans, and fishes. A. japonicus showed ontogenetic changes in feeding habits. Smaller individuals (6-10 cm, TL) fed mainly on amphipods. The proportion of amphipods decreased as body size increased, whereas the consumption of euphausiids gradually increased (10-14 cm, TL). As the body size more increased, the proportion of amphipods increased whereas euphausiids decreased (14-26 cm, TL).

• Korean Journal of Fisheries and Aquatic Sciences
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• v.51 no.3
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• pp.230-237
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• 2018

This study investigated the food and nutritional characteristics of alkaline-insoluble fractions (AIFs) recovered from bastard halibut Paralichthys olivaceus (BH) and skipjack tuna Katsuwonus pelamis (ST) roes using the alkaline solubilization. The moisture content of AIFs ranged from 4.8% to 12.8%, and ST provided significantly better yields (9.5 for STAIF-11 and 7.1 g/100 g roe for STAIF-12) than did BH (P<0.05). The protein content of AIFs ranged from 71.7% to 79.2%, with the highest level yielded by STAIF-11 (6.8 g/100 g roe). The crude fat content of AIFs was 10.9-14.3% and the mineral content was 0.7-3.4%. The major mineral components of AIFs were sulfur, sodium, potassium, and phosphorus. Color values showed that BHAIFs were significantly brighter than STAIFs. Total contents of essential amino acids were significantly higher in STAIFs (47.5-49.5%) than in BHAIFs. The major essential amino acids found in AIFs from both sources were Val, Leu, Lys, and Arg. Therefore, AIFs were significantly superior to whole BH roe in terms of physicochemical and nutritional status, and we identified species-specific differences between BH and ST. Protein is a major component of AIFs recovered from fish roes, which suggests that they have potential for use as a protein source.

• Journal of the Korean Society of Food Science and Nutrition
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• v.36 no.7
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• pp.881-888
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• 2007

For the use of skipjack tuna cooking drip (STC) as a source of functional seasoning, the STC was hydrolyzed with various commercial enzymes, such as Alcalase, Flavourzyme, Neutrase and Protamex, and its hydrolysate was also investigated on the food component characteristics. The hydrolysate incubated with Alcalase for 30 min (HA30) showed 56.8% for angiotensin I converting enzyme (ACE) inhibitory activity and 1.18 for antioxidative activity, which were high or similar compared to the other enzymatic hydrolysates. There were no differences in ACE inhibitory activity and antioxidative activity among HA30, two-step enzymatic hydrolysates, and ultrafilterates (molecular weight cut off, 10 kDa). The HA30 was very stable on the digestive enzymes, such as chymotrypsin, pepsin, trypsin according to the TCA (trichloroacetic acid) soluble index. The results suggested that skipjack tuna cooking drip could be used as a source for preparing functional seasoning sauce.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.42 no.3
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• pp.197-203
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• 2009

This study was conducted to investigate the food components of cooking drips from shell oysters steamed under various retort pressures. Among the drips from shell oyster steamed under different retort pressures (1.0, 2.0, 2.5, 3.0, 3.5, 4.0 and 4.5 kg/$cm^2$) the oyster drip obtained at the 4.5 kg/$cm^2$ of retort pressure had the highest degree of brix, yield, crude protein, glycogen and trichloroacetic acid soluble-N contents, while its salinity was the lowest. In the results of food safety test, the presence of E. coli (18 MPN/100 g>) and viable cell (30 CFU/g>) in the oyster drip was in acceptable level as a food-stuff. However, the sensory evaluation such as color, flavor and taste, total amino acid and free amino acid contents of cooking drip from shell oyster steamed at 4.5 kg/$cm^2$ were inferior to those of oyster wash water. Differences in the major amino acids of total amino acid and free amino acid between oyster cooking drip and oyster wash water were also found. The results suggested that the effective use methods of oyster cooking drip should be investigated.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.43 no.4
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• pp.285-292
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• 2010

To prepare high-quality fast foods using salmon, this study developed a docosahexaenoic acid (DHA)-enriched salmon patty, and compared its quality with soybean oil-added patty and commercial patty. The moisture and lipid contents of the DHA-enriched patty were 61.9% and 7.7%, respectively. The moisture content was lower than in the commercial patty, while the lipid content was higher. The lipophilic and hydrophilic browning indices of the DHA-enriched patty were 0.10 and 0.05, respectively, which were lower than those of the commercial patty. The DHA-enriched patty had 5% less trichloroacetic acid (TCA)-soluble nitrogen than the commercial patty, and it was firmer. There were no differences in the proximate composition, browning indices, TCA-soluble nitrogen content, and hardness between the soybean-added and DHA-enriched patties prepared in this experiment. Examining the fatty acid compositions of the patties, the saturated acid and monoenoic acid compositions decreased in the following order: DHA-enriched patty > soybean oil-added patty > commercial patty, while the polyenoic acid composition increased in that order. The total amino acid content of the DHA-enriched patty was 19.13 g/100 g, which was 32% higher than that of the commercial patty (14.47 g/100 g). No enriching effect of minerals would be expected on eating a 100 g DHA-enriched patty, except for phosphorus. The sensory evaluation indicated that the DHA-enriched patty was superior in color and taste to the commercial patty, while there was no difference in flavor between the patties.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.42 no.2
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• pp.116-122
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• 2009

This study was conducted to compare the food quality of commercial salt-fermented silver-stripe round herring (SFS) to that of commercial salt-fermented anchovy (SFA). The contents of moisture and crude protein of SFS were higher than those of SFA. However, the crude lipid and crude ash contents of SFS were lower than those of SFA. The salinity of SFS was 13.2%, which was lower than that of SFA. The taste value of SFS was 148.1, which was higher than that of SFA. The total amino acid content of SFS was 18.1 g/100 g and its major amino acids were glutamic acid (9.5%) and aspartic acid (8.1%). The contents of calcium, phosphorus and iron in SFS were 647 mg/100 g, 363 mg/100 g and 4.1 mg/100 g, respectively. Twenty six types of fatty acids were detected in SFS and the major components were 16:0, 18:0, 18:1n-9 and 22:6n-3. The angiotensin I converting enzyme (ACE) inhibiting and the antioxidative abilities of SFS were 50.0% and 1.15, respectively, which were similar to those of SFA. Sensory evaluation revealed that SFS had a superior taste and color to SFS, while to the flavor of two products was similar.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.42 no.6
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• pp.537-544
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• 2009

This study was conducted to improve yield and functional properties of autoclave-treated salmon frame extracts (SFETA) using commercial enzymes (Alcalase 2.4 L FG, Flavourzyme 500 MG, Neutrase 0.8 L and Protamex 1.5 MG). Yield and angiotensin I converting enzyme (ACE) inhibitory activity of all enzymatic hydrolysates improved compared to those of control (undigested extracts), which were the highest in hydrolysates incubated with Protamex 1.5 MG for 4 hrs (P4-treated hydrolysates) and 2 hrs (P2-treated hydrolysates), respectively. However, antioxidant activities of all enzymatic hydrolysates showed less than 29%. According to the trichloroacetic acid soluble-N, volatile component intensity and sensory evaluation, when compared to control, taste of P4-treated hydrolysates improved, while its fish odor strongly smelt. Therefore, for efficient use of P4-hydrolysates, the fish odor should be improved by Maillard reaction of extracts or pre-treatment of salmon frame.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.52 no.4
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• pp.430-436
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• 2019

The diet of Glyptocephalus stelleri was studied using 475 specimens collected in the coastal waters of the East Sea of Korea. The specimens ranged from 6.8 to 43.4 cm in total length (TL). G. stelleri was a crustacean feeder that consumed mainly euphausiids [percent index of relative importance (%IRI)=63.7%]. Polychaetes were the second largest prey component. The diet also included small quantities of bivalves, copepods, amphipods and shrimps. Individuals smaller than 15 cm TL fed mainly on euphausiids. The proportion of euphausiids decreased as body size increased, whereas the consumption of polychaetes increased gradually.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.51 no.6
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• pp.640-646
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• 2018

To determine whether there are differences in the food component characteristics of the cultured recessive small-sized abalone Haliotis discus hannai (SA; 30-40 each/kg) and middle-sized abalone (MA; 10-15 each/kg), the proximate compositions, fatty acid and total amino acid compositions of these two species were evaluated. Additionally, extraction methods were performed on the SA to asses the quality characteristics of the resulting. In terms of proximate composition, MA had lower moisture and carbohydrate levels and higher crude protein contents than SA. The total amino acid contents of MA and SA were 15,734.4 and 11,379.1 mg/100 g, respectively, the major amino acids were glutamic acid, aspartic acid, serine, glycine, alanine, leucine, arginine and lysine, and the major fatty acids were 16:0, 18:0, 18:1n-9, 18:1n-7, 20:4n-6, 20:5n-3, and 22:5n-3. The pH levels and total nitrogen and amino nitrogen contents of the hot-water extract (WE) and scrap enzyme hydrolysate (SE) samples from the SA were 6.32 and 6.05, 1.36% and 1.52%, and 342.1 and 403.1 mg/100 g, respectively. The extraction yields and free amino acid contents from SA were 1,317 and 440 mL/kg, and 8,721.1 and 9,070.7 mg/100 g, respectively, and the concentrations of major components were as follows: arginine, glycine, glutamic acid, alanine and lysine. Additionally, the complex extract (WE+SE) was superior to the traditional extract (WE) in terms of extraction yield, amino-nitrogen content, and organoleptic qualities but not odor.