• Korean Journal of Fisheries and Aquatic Sciences
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• v.15 no.3
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• pp.185-190
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• 1982

In utilization of small size red muscled fishes like mackerel, sardine, and filefish, mechanical dressing is usually required. The removal of dark muscle is also necessary to improve qualify of the product, which could hardly be done by mechanical process. As a method of separating dark muscle, specific gravity method using sugar solution was investigated in this study. And the effects of the level of specific gravity, the size and density of meat particles, and stability of meat particle float on the separation of dark muscle were discussed. From the results, effective specific gravity, in case of sucrose solution, ranged 1.067 to 1.072 for mackerel, 1.062 to 1.070 for sardine, and 1.072 to 1.077 for filefish, respectively. The maximum separation of more than $90\%$ was obtained at specific gravity of 1.075, 1.070, and 1.075 in cases of mackerel, sardine and filefish, respectively. The size of meat particles which were ground with 0.2cm orifice plate was adequate to yield $90\%$ separation or above. The meat particle float in the glucose solution began to precipitate within 5 minutes after separation while 25 minutes in case of sucrose solution. Lipids were also fairly removed by the dark muscle separation process.

• Journal of Life Science
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• v.10 no.5
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• pp.436-446
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• 2000

This study was conducted to investigate the effects of different dietary enzymatic hydrolysates using squid and mackerel by-product on feed efficiency, growth and chemical composition in Korean rockfish (Sebastes schlegeli) after a eight weeks feeding experiment. Effects on the weight gain and feed efficiency in the enzymatic hydrolysates added groups were very effective. Weight gain were significantly higher in the squid hydrolysates whole added group than in the other groups. Moisture and crude ash contents of muscle were not significantly affected by hydrolysates supplementation in all groups. Crude protein and lipid contents of muscle were increased after eight weeks feeding trial. Amino acid contents of muscle were higher in squid hydrolysates whole added group than in the other groups. Amino acids were not affected by hydrolysates supplementation in all groups. Fatty acid contents of muscle were increased after eight weeks growth trial. Fatty acids were not significantly different in the dietary groups.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.42 no.5
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• pp.411-416
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• 2009

Proximate compositions and fatty acid profiles of cultured and wild mackerel (Scomber japonicus) muscles were compared. Protein content ranged from approximately 16% to 18% and was higher in wild fish than in cultured ones. Lipid content was between two to four times higher in large and small cultured fish (20.1-20.5%) compared with same sized wild fish. The prominent non-polar lipid (NL) class in fish muscles was triglyceride, and additionally, free sterol was among the prominent NL classes in wild fish muscles. Prominent phospholipid (PL) classes in cultured and wild fish muscles were phosphatidylethanolamine and phosphatidylcholine, with the former being higher in cultured fish and the latter higher in wild fish. Prominent fatty acids of total lipid were 16:0, 18:1n-9, 22:6n-3 (docosahexaenoic acid, DHA), 20:5n-3 (eicosapentaenoic acid, EPA), 16:1n-7, 18:0 and 14:0, while 18:2n-6 was among the prominent fatty acids in cultured fish. The n-3 polyunsaturated fatty acids (PUFA, DHA+EPA) content (in mg/100 g of muscle tissue) was higher in cultured fish (2,711 mg in large fish and 2,572 mg in small fish) than in wild fish (2,431 mg in large fish and 1,398 mg in small fish). In conclusion, we have been able to demonstrate that cultured mackerel could also be a good sources of n-3 PUFA, such as DHA and EPA.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.44 no.3
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• pp.183-190
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• 2011

This study was performed to assess the antioxidative properties of lipid from aquacultured mackerel Scomber japonicus fed with a diet fortified with conjugated linoleic acid (CLA) and ascidian Halocynthia roretzi tunic extracts by radical scavenging assay. The fish were separated into squid oil (Control) and 2.5% CLA (CA25) groups during the 8-week feeding period. The reducing power of each sample showed high levels of activity compared with ${\alpha}$-tocopherol and butylated-hydroxyanisol (BHA) at 0.2-1.0 mg/mL of lipid. Inhibition of linoleic acid oxidation in samples from Control and CA25 groups showed similar activity after 2 days of incubation at $40^{\circ}C$. The 2,2-diphenyl-1-picrylhydrazyl (DPPH), superoxide, and hydroxyl radical scavenging activities of CLA and carotenoid-deposited sample (CA25) were higher than those of the Control group. The results indicated that the lipid extracted from the viscera of mackerel showed slightly higher antioxidant activities than that from the muscle.

• Journal of the Korean Society of Food Science and Nutrition
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• v.42 no.8
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• pp.1263-1269
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• 2013

This study was conducted in order to investigate the inhibitory effects of natural materials on histamine production in mackerel. Antimicrobial activities on Photobacterium phosphoreum of medicinal herbs and seaweeds were investigated using the paper disc assay and MIC (minimum inhibitory concentration) test. According to the results, Sargassum sagamianum and Ecklonia cava ethanol extracts exhibited antibacterial activity. In particular, Sargassum sagamianum ethanol extract showed excellent antibacterial activity at 0.015625 mg/mL by the MIC test. Anti-histamine release activities of natural materials were further investigated by examining their inhibitory effects on histidine decarboxylase (HDC) activity in the crude enzyme preparation from Photobacterium phosphoreum. The ethanol extracts of Ecklonia cava and Eisenia bicyclis exhibited the strongest HDC inhibitory activity, with 32% and 22%, at a concentration of 1 mg/mL, respectively. Therefore, natural materials may reduce histamine poisoning through decrease of histamine production in mackerel.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.44 no.3
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• pp.174-183
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• 2008

In order to develop the substitutive materials for natural baits of swimming crab pots, the fluorescent characteristics of the baits were analyzed, and the preference of fluorescent dyes were investigated by the mean entrapped catch number to the pots through the water tank experiments and fishing experiments. On the investigation of fluorescent characteristics by the 5 kinds of baits, mackerel, krill, manila clam, pig's fat and chicken's head which were used in substitutive baits for test in the UV long wave(365nm) area, it showed clear blue fluorescence in the skin of mackerel, shell of krill, manila clam and bill of chicken's head, and green fluorescence in the mackerel s muscle and internals, and yellow fluorescence in the pig's fat and chicken's head. On the investigation of fluorescent characteristics by the bait cages in the UV short wave(254nm) and long wave(365nm) area, it showed each green, red and blue fluorescence in the cylinderical or hexahedral red plastic bait cages which were painted each green, red and blue fluorescence dyes, but it showed yellowish green flourescence in the cylinderical or hexahedral red plastic bait cage which was painted yellow fluorescent dye. On the preference investigation of the fluorescent dyes of swimming crabs by the 5 kinds of the bait cages which were put the mackerel in the non-fluorescent red plastic cage($RF_N$), red, yellow, green and blue fluorescent plastic cages(RF, YF, GF, BF) each, nonfluorescent red plastic cage($RF_N$) was entrapped mean 2.0(6.7%), but blue fluorescent plastic cage(BF) was mean 5.0(16.7%) and it was more 2.5 times comparing to $RF_N$, and red fluorescent cage(RF) was same level and green fluorescent cage(GF) was 50% of catch number comparing to $RF_N$, and yellow fluorescent cage(YF) was entrapped nothing(F 46.324, P < 0.05). On the investigation of the entrapped catch number to the pots which were put the mackerel in the blue fluorescent hexahedral plastic cage(HP) and blue fluorescent silicon mackerel model cage(SM), HP was mean 3.4(11.3%) and it was a little more comparing to SM which was entrapped mean 3.2(10.7%)(t 0.775, P > 0.05). Fishing experiments on the preference investigation of swimming crabs by the pots which were put in the non-fluorescent red plastic cage($RF_N$) and blue fluorescent plastic cage(BF) were conducted 3 times. Mean catching number and weight of $RF_N$ were 71.7 ind.(18.3%) and 16.9kg(64.3%), and those of BF were 93.0 ind.(23.1%) and 19.8kg(64.5%), respectively.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.17 no.4
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• pp.313-320
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• 1984

In order to elucidate the oxidative stabilities of mackerel lipids, lipids were extracted from ordinary muscle, dark muscle, skin (including subcutaneous adipose tissue) and viscera, and then stored at $30^{\circ}C$. The changes of lipids were examined periodically by measuring peroxide value (POV), thiobarbituric acid (TBA), weighing method, acid value (AV) and iodine value (IV), Fatty acid composition of lipids was analyzed by GLC. The results obtained are summerized as follows: The velocity of lipid oxidation during the storage was differ from the extracting part of the sample. It was laster in skin, viscera, dark muscle and ordinary muscle in the order. Ratio of polar lipid fractions in total lipids was ranged from 5 to $15\%$, and the highest result was observed in dark muscle. Main fatty acids of the lipids were $C_{16:0}$ acid ($22.0{\sim}25.9\%$), $C_{18:1}$ acid ($22.3{\sim}26.7\%$) and $C_{22:6}$ acid ($9.6{\sim}13.4\%$), and $C_{22:6}$ acid content ($\%$) was the highest in lipid from dark muscle, and the lowest in lipid from skin. Monoenoic acid content ($\%$) was higher in the non-polar lipid than in the polar lipid, on the contrary. polyenoic acid content ($\%$) was higher in the polar lipid than in the non-polar lipid. Polyunsaturated fatty acids of the lipids, $C_{20:5}$ acid and $C_{22:6}$ acid, decreased predominantly with oxidation during storage, while saturated acids, $C_{14:0}$ acid and $C_{16:0}$ acid, increased predominantly. The polar lipid fractions were oxidized much faster than the non-polar lipid fractions.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.18 no.4
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• pp.352-362
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• 1985

In succession to the previous paper, the present study was directed to investigate the optimal processing conditions of meat paste products with mackerel. To improve the gel forming ability of meat paste, washing conditions with water and alkaline solution, setting time and temperature, and heating temperature were controlled, and the influences of the freshness of raw mackerel and mixing ratios of ordinary and dark muscle on the qualities of meat paste products were discussed. The most effective condition for the keeping freshness of raw mackerel meat among different storage conditions was the forozen storage at $-20^{\circ}C$, followed by the storage at $-3^{\circ}C$ and ice storages, and this relation was coincided with the effect for maintaining of gel forming ability among above conditions, but there was no effect on keeping freshness of raw mackerel in the storage at $25^{\circ}C$. Gel strength of meat washed with tap water decreased with washing time, particularly, the meat washed three times showed higher gel strength than the meat washed more than 5 times. And the removal ratios of water soluble protein were $60\%$ in the meat washed three times and $90\%$ in the meat washed nine times. Washing effect of raw mackerel meat with alkaline solution was great at pH $6.5{\sim}7.0$ of meat paste yielding the highest gel strength in the meat washed with $0.5\%$ sodium bicarbonate solution. Gel strength of meat paste product decreased with the increase of mixing ratios of ordinary and dark muscle in the raw meat. In the setting conditions of meat paste examined, 15 hours at $5^{\circ}C$ and 2 hours at $30^{\circ}C$. The most suitable temperature for gel forming in heating conditions was $90^{\circ}C$, fellowed by $100^{\circ}C\;and\;80^{\circ}C$.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.33 no.2
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• pp.153-157
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• 2000

Hydrolysate which inhibit the Angiotensin I-converting enzyme (ACE) was prepared from mackerel muscle by pretense. The ACE inhibitory activity of mackerel muscle hvdrolysate (MMH) was $967 {\mu}g of IC_(50)$. ACE inhibitory peptides were isolated by ultrafiltration, gel permeation column chromatography (GPC), reversed phase column chromatography(RPC), reversed phasehigh performance liquid chromatography (RP-HPLC), and gel permeation high performance liquid chromatography (GP-HPLC) from the MMH. The amino acid sequence of the ACE inhibitory peptides was Tyr-Val-Ala. The $IC_(50)$ of this peptide for ACE from rabbit lung was $1.4 {\mu}M$.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.52 no.2
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• pp.130-140
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• 2016

This study analyzed annual catch trend during 45 years and monthly catch of the least 10 years (2005~2014) for chub mackerel caught in the Korean coastal waters. To determine fishing status of chub mackerel, fork length measurements were conducted at least twice every week for 100 individuals randomly selected at the Busan Cooperative Fish Market from January of 2012 to December of 2014; and biological characteristics and proximate composition (moisture, protein, fat, ash) were analyzed by length class (I~IV) on a monthly basis from January to December of 2014. Monthly catch trend showed low level below 5,000 mt from February to July, whereas high level above 15,000 mt from October to December. For the period between 2012 and 2014, annual average catch proportion of juvenile were relatively high at 68.1%, 53.1% and 53.2% from January to April, before spawning season, while those were low at 21.5%, 20.7% and 29.12% from June to November. As for the change in the proximate composition per 100 g of muscle, protein and ash did not change much by seasons and length class, whereas fat and moisture contents showed large fluctuations and complementary relationship between the two factors. Regardless of length class, monthly average fat content, containing Omega-3, showed the lowest at 7.18 g in April and highest at 19.27 g in December, which exhibited 2.6 times difference from one another. Regardless of fishing seasons, fat content by length class were 19.06 g for the class I and 6.43 g for the class IV, which showed three times difference. Fat contents of the class I were high at 26.97 g and 27.19 g in November and December, while low at 8.37 g and 9.99 g in April and May. Especially, fat contents from January to May were 5.0 g, which was the lowest. Therefore, it is expected that consumer could indirectly contribute fisheries management through their understanding and wise consumption based on fishing status and fluctuation of proximate composition.