• Journal of Food Hygiene and Safety
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• v.30 no.2
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• pp.166-172
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• 2015

This study was performed to develop treatment method for reducing microbial contamination on Daruma (a semi-processed product of seasoned and dried squid) by combination of strong acidic hypochlorous water (SAHW) and ultrasonic waves (UW). The available chlorine concentration, oxidation reduction potential (ORP) and pH of SAHW were $69.67{\pm}0.58ppm$, $1071.33{\pm}4.16mV$ and 2.79, respectively. The 1.49 log CFU/g of viable cell count and 1.32 log CFU/g of Staphylococcus aureus was reduced, and Escherichia coli was reduced below detection limit when the Daruma was treated with 20 times (w/v) of sodium hypochlorite solution (SHS) for 120 min. The 3.62 log CFU/g of viable cell count and 3.22 log CFU/g of Staphylococcus aureus was reduced, and Escherichia coli was reduced below detection limit when the Daruma was treated with 20 times (w/v) of SAHW for 120 min. The antibacterial effects of SAHW were stronger than those of SHS at same available chroline concentration. SAHW treatment after washing strongly alkalic electrolyzed water (SAEW) showed better bactericidal effects than SAHW treatment only. The 4.0 log CFU/g of viable cell count was reduced, S. aureus was reduced below regulation limit (Log 2.0 CFU/g), and E. coli was reduced below detection limit when the Daruma was treated with 20 times (w/v) of SAHW for 90 min after washing with 20 times (w/v) of SAEW for 60 min. The viable cell number was reduced below detection limit and S. aureus was reduced below regulation limit when the Daruma was treated with 20 times (w/v) of SAHW for 60 min in ultrasonic washer. E. coli was reduced below detection limit when the Daruma was treated with 20 times (w/v) of SAHW for 10 min in ultrasonic washer. These results suggest that combination of SAHW and UW may be a good technique to reduce the microbial contamination in daruma.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.55 no.2
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• pp.111-120
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• 2022

This study was conducted to prepare braised product with soy sauce (BP), rose gratin (RG) and white mousse (WM) using Japanese Spanish mackerel Scombermorus niphonius as senior-friendly seafoods with different physical and nutritional properties and to examine their quality characteristics. The hardness of BP, RG and WM were 428.0×10³, 46.9×10³ and 16.0×10³ N/m², respectively. The nutritional values of BP, RG and WM are 17.8, 9.1 and 18.5 g, respectively, for protein; 11.86, 23.32 and 13.35 ㎍ RAE, respectively, for vitamin A; 1.27, 0.49 and 0.17 ㎍, respectively, for vitamin D; 45.21, 12.79, and 35.54 mg, respectively, for vitamin C; 0.17, 0.13 and 0.23 mg, respectively, for riboflavin; 4.28, 2.94 and 3.65 mgNE, respectively, for niacin; 19.6, 104.0 and 48.1 mg, respectively, for Ca; 441.6, 271.1 and 250.1 mg, respectively, for K; 0.20, 0.80 mg and undetection, respectively, for dietary fiber. Escherichia coli was undetected in all the products. These results indicated that the products be classified as steps 1 for BP, step 2 for RG and step 3 for WM of senior-friendly seafoods based on the KS, and as nutritional and physical properties-improved senior-friendly seafoods based on the Food Code.

• Journal of Food Hygiene and Safety
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• v.36 no.4
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• pp.289-297
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• 2021

In this study, multiplex PCR and real-time PCR were performed on Theragra chalcogramma (walleye pollock), Pangasianodon hypophthalmus (iridescent shark) and their processed foods, such as changnan-jeot and gaiyang-jeot (salted iridescent shark intestine). Species-specific primers for T. chalcogramma and P. hypophthalmus were designed, and genomic DNA was directly extracted from each sample to perform single PCR and multiplex PCR. As a result of PCR, in the case of single PCR, PCR bands of T. chalcogramma (297 bp) and P. hypophthalmus (132 bp) were identified, and in the case of multiplex PCR, it was confirmed that amplification occurred without cross-reaction between T. chalcogramma and P. hypophthalmus. As a result of checking the PCR sensitivity, the concentration of genomic DNA was detected up to 0.1 ng/µL in both single PCR and multiplex PCR. The real-time PCR results showed that the average Ct value of T. chalcogramma was 20.765±0.691, and the average Ct value of P. hypophthalmus sample was 35.719±1.828 in the T. chalcogramma species-specific primers. In the P. hypophthalmus species-specific primers, the average Ct value of the T. chalcogramma sample was 35.996±1.423, and the mean Ct value of the P. hypophthalmus sample was 20.096±0.793. These results demonstrated the significant differences in the efficiency, specificity and cross-reactivity of species-specific primers in real-time PCR. Based on these findings, 7 of changnan-jeot or gaiyang-jeot products were confirmed by multiplex PCR and real-time PCR, and valid results were confirmed in all samples.

• Journal of Applied Biological Chemistry
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• v.52 no.3
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• pp.93-102
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• 2009

Polyunsaturated fatty acids (PUFA), especially eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) have significantly beneficial effects on health in relation to cardiovascular, immune, and inflammatory conditions and they are involved in determining the biophysical properties of membranes as well as being precursors for signaling molecules. PUFA biosynthesis is catalyzed by sequential desaturation and fatty acyl elongation reactions. This aerobic biosynthetic pathway was thought to be taxonomically conserved, but an alternative anaerobic pathway for the biosynthesis of PUFA is now known to contain analogous polyketide synthases (PKS). Certain fish oil can be a rich source of PUFA although processed marine oil is generally undesirable as food ingredients because of the associated objectionable flavors that are difficult and cost-prohibitive to remove. Oil-seed plants contain only the 18-carbon polyunsaturated fatty acid alpha-linolenic acid, which is not converted in the human body to EPA and DHA. It is now possible to engineer common oilseeds which can produce EPA and DHA and this has been the focus of a number of academic and industrial research groups. Recent advances and future prospects in the production of EPA and DHA in oilseed crops are discussed here.

• Microbiology and Biotechnology Letters
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• v.18 no.1
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• pp.18-25
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• 1990

Paralytic Shellfish Poison (PSP) is mainly produced by marine dinoflagellates such as Protogonyaulax sp. and Pyrodinium sp.. The PSP was known to be accumulated in digestive gland of shellfish as result of feeding toxic dinoflagellates. PSP illness when occurs when one eats PSP intoxicated shellfish. Therefore PSP is becoming as serious problem in food hygiene and shellfish cultivation industry. The purpose of this study was to develop detoxification method for utilization of PSP intoxicated sea mussel and prevent from PSP illness. The PSP was extracted with 0.1 N HCl solution from the submitted sea mussel, then the toxicity was measured by mouse assay according to Official Methods of Analysis of the Association of Official Analytical Chemists. No detoxification effect was observed by adding extracted juice of garlic and ginger. When the sea mussel homogenate was heated at various temperatures, the PSP toxicity was not changed significantly at below $70^{\circ}C$ for 60 minutes but it was decreased as the heating temperature was increased. For example, when the sea mussel homogenate was heated at 100, $121^{\circ}C$ for 10 minutes, the toxicity was decreased about 67 and 90%, respectively. When the sea mussel containing 645 $\mu$g PSP per 100g of edible meat was processed according to general shellfish canning procedure, the toxicity was decreased as the level of PSP undetected by mouse assay.

• Journal of Life Science
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• v.31 no.6
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• pp.559-567
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• 2021

This study compared the nutritional characteristics and antioxidant effects of sea mustards sourced from five different areas (Barammaegi, Gultongmeori, Chanmulgae, Johongtaek, and Goraedeung) in Taejongdae, Youngdo, Busan. The contents of total flavonoids and phenols and fatty acid composition were measured. To evaluate their antioxidant effects, 1,1-diphenyl-2-picrylhydrazyl (DPPH) and 2,2'-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) assays were used. Acetone/methylene chloride (A+M) extracts from all the sea mustards contained higher amounts of total flavonoids and phenols than methanol (MeOH) extracts. Among the sea mustards obtained from the different areas, the total flavonoid and total phenolic content of the A+M extract of the sea mustard from Gultongmeori was 1.44±0.04 mg/g and 1.72±0.06 mg/g, respectively. In terms of the fatty acid composition, the Gultongmeori sea mustard had higher percentages of total n-6, total n-3, eicosapentaenoic acid (EPA, 20:5n-3), and docosahexaenoic acid (DHA, 22:6n-3) than the sea mustards from the other areas. The A+M extract of the sea mustard from Gultongmeori was more effective in terms of scavenging free radicals as compared with that of the other sea mustards, as assessed by the DPPH and ABTS assays (p<0.05). In a 120-minute reactive oxygen species (ROS) production assay, all the extracts tested decreased cellular ROS production induced by H₂O₂ compared to that produced by exposure to an extract-free control (p<0.05). The extracts from Barammaegi and Gultongmeori had a greater inhibitory effect on cellular ROS production. These results indicated that the antioxidant effects of sea mustards might be associated with a higher amount of flavonoids and phenols. This study suggests that food-processed products from sea mustard can be developed as functional foods for promoting health in the local population.

• Korean Journal of Food Science and Technology
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• v.28 no.6
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• pp.1038-1044
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• 1996

The salt-fermented anchovy sauce (AS) was packed in round No. 307-1 can, and thermally processed at $121.1^{\circ}C$ to obtain Fo values of 3, 5 and 10. The changes of food components and qualifies by thermal processing of sterilized AS (RAS) were examined. The compositions of AS were as followed; pH 6.81, VBN 394.7 mg/100g, total nitrogen 2,195.5 mg%, amino-nitrogen 1,010.5 mg%, and acidity 10.5 ml. Viable cell counts of AS on 0%, 5%, 20% NaCl-medium were $2.9{\times}10^3,\;9.1{\times}10^3$ and not detected, respectively. And viable cell counts of RAS were not detected. Acidity, total nitrogen and amino nitrogen contents of AS decreased slightly with the severeness of heat treatments, whereas pH and VBN content were increased. Total free amino acid contents of raw AS and RAS were 12,802.5 mg% and $11,212.6{\sim}12,105.4\;mg%$, and major amino acids were alanine, glutamic acid, leucine, isoleucine, valine and lysine. Also contents of IMP, hypoxanthine, TMAO and TMA in AS and RAS were 42.1 mg% and $35.5{\sim}40.9\;mg%$, 103.7 mg% and $103.1{\sim}105.5\;mg%$, 78.8 mg% and $58.2{\sim}71.6\;mg%$, 55.8 mg% and $58.9{\sim}68.5\;mg%$ respectively. And a little changes were observed in whole volatile components of AS with severeness of heat treatments by GC chromatogram patterns. Judging from the chemical and sensory evaluations, the Fo 3 heat treatment sample was not inferior to raw AS, and maintained good quality for 1 year storage.

• Ocean and Polar Research
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• v.34 no.4
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• pp.365-384
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• 2012

Microalgae are photosynthetic microorganisms that are highly productive in the presence of basic renewable natural sources (light, $CO_2$, water and nutrients). They can synthesize lipids, carbohydrates and proteins in a small number of days. Subsequently, these carbon-captured products can be processed into both biofuels and valuable co-products. Additionally, microalgae would be an ideal feedstock for replacing land-based food crops with cellular products as high energy density transportation fuels. These microscopic organisms could contribute a significant amount of renewable energy on a global scale. In Korea, microalgae biofuel research was common in the early 1990s. The research activities were unfortunately stopped due to limited governmental funds and low petroleum prices. Interest in algal biofuels in Korea has been growing recently due to an increased concern over oil prices, energy security, greenhouse gas emissions, and the potential for other biofuel feedstock to compete for limited agricultural resources. The high productivity of microalgae suggests that much of the Korean transportation fuel requirements can be met by biofuels at a production cost competitive with the increasing cost of petroleum seen in early 2008. At this time, the development of microlalgal biomass production technology remains in its infancy. This study reviewed microalgae culture systems and biomass production, harvesting, oil extraction, conversion, and technoeconomical bottlenecks. Many technical and economic barriers to using microalgal biofuels need to be overcome before mass production of microalgal-derived fuel substitutes is possible. However, serious efforts to overcome these barriers could become a large-scale commercial reality. Overall, this study provides a brief overview of the past few decades of global microalgal research.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.9 no.2
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• pp.79-110
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• 1976

In Korea fermented fish and shellfish have traditionally been favored and consumed as seasonings or further processed for fish sauce. Three major items in production quantity among more than thirty kinds which are presently available in the market are fermented anchovy, oyster and small shrimp. They are usually used as a seasoning mixture of Kimchi in order to provide a distinctive flavor. Fermented small shrimp, Acetes chinensis is most widely and largely used ana occupies an important position in food industry of this country. But no study on its taste compounds has been reported. This study was attempted to establish the basic data for evaluating taste compounds of fermented small shrimp. The changes of such compounds during fermentation as free amino acids, nucleotides and their related compounds, TMAO, TMA, and betaine were analysed. In addition, change in microflora during the fermentation under the halophilic circumstance was also investigated. The samples were prepared with three different salt contents of 20, 30 and $40\%$ to obtain the proper degree of fermentation at a controlled tempeature of $20{\pm}2^{\circ}C$. The results are summarized as follows: Volatile basic nitrogen increased rapidly until 108 days of fermentation and afterwards it tended to increase slowly. Amino nitrogen also increased rapidly until 43 days of fermentation and then increased slowly. Extract nitrogen increased and marked the maximum value at 72 day fermentation and then decreased slowly. ADP, AMP and IMP tended to degrade rapidly while hypoxanthine increased remarkably at 27 day fermentation but slightly decreased at 72 day fermentation. It is presumed that the characteristic flavor of fermented small shrimp might be attributed to the relatively higher content of hypoxanthine. In the free amino acid composition of fresh small shrimp abundant amino acids were proline, arginine, alanine, glycine, lysine, glutamic acid, leucine, valine and threonine in order. Such amino acids like serine, methionine, isoleucine, phenylalanine, aspartic acid, tyrosine and histidine were poor. In small shrimp extract, proline, arginine, alanine, glycine, lysine and glutamic acid were dominant holding $18.5\%,\;14.6\%,\;10.8\%,\;8.7\%,\;8.1\%\;and\;7.7\%$ of total free amino acids respectively. The total free amino acid nitrogen in fresh small shrimp was $63.9\%$ of its extract nitrogen. The change of free amino acid composition in the extract of small shrimp during fermentation was not observed. Lysine, alanine glutamic acid, proline, glycine and leucine were abundant in both fresh sample and fermented products. The increase of total free amino acids during 72 day fermentation reached approximately more than 2 times as compared with that of fresh sample and then decreased slowly. Fermented small shrimp with $40\%$ of salt was too salty to be commercial quality as the results of organoleptic test showed. It is found that 72 day fermentation with $20\%\;and\;30\%$ of salt gave the most favorable flavor. It is convinced that the characteristic flavor of fermented small shrimp was also attributed to such amino acids as lysine, proline, alanine, glycine and serine known as sweet compounds, as glutamic acid with meaty taste, and as leucine known as bitter taste. The amount of betaine increased during fermentation and reached the maximum at 72 day fermentation and then decreased slowly TMA increased while TMAO decreased during fermentation. The amount of TMAO nitrogen in fermented small shrimp was $200mg\%$ on moisture and salt free base. Betaine and TMAO known as sweet compounds were abundant in fermented small shrimp. It is supposed that these compounds could also play a role as important taste compounds of fermented small shrimp. At the initial stage of fermentation, Achromobacter, Pseudomonas, Micrococcus denitrificans which belong to marine bacteria were isolated. After 40 day fermentation, they disappeared rapidly while Halabacterium, Pediococcus, Sarcian, Micrococcus morrhuae and the yeasts such as Saccharomyces sp. and Torulopsis sp. dominated. It is concluded that the most important taste compounds of fermented small shrimp were amino acids such as lysine, proline, alanine, glycine, serine, glutamic acid, and leucine, betaine, TMAO and hypoxanthine.

• Journal of Fisheries and Marine Sciences Education
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• v.27 no.4
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• pp.1084-1091
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• 2015

Aquaculture of olive flounder started in the middle of 1980's and now farming has been taken place in many places along the coastal line in Korea. The taste of olive flounder has a good chewy texture because of high collagen content, low fat content, so it is popular for sliced raw fish. Olive flounder is popular among Koreans but the consumption pattern is uniformly so as to be used as sliced raw fish but not other ways. So, now there needs to develop high valued-processed food using olive flounder. This study was set to investigate the processing of terrine by using olive flounder, in which terrine is French style meat loaf that is well favored around the world. In this study, terrine was prepared by chopping olive flounder meat with 39 g egg white and 10 mL fresh cream (per 50 g fillet) and then seasoned with 5 mL lemon juice, 5 mL brandy, 0.05 g salt and 0.05 g pepper. The 25 g of dough was placed on a vinyl wrap, put with 2 g cheese, and layered an another 25 g dough, and then rolled up and wrapped by aluminium foil. Two different cooking methods were used for terrine processing in this study. Terrine-1 was cooked by vacuum sealed in polyethylene film ($20{\times}30{\times}0.05mm$) after boiling for 5 min and stored at $-20^{\circ}C$ for 7 days. Terrine-2 was prepared by vacuum sealed in polyethylene film ($20{\times}30{\times}0.05mm$) and stored at $-20^{\circ}C$ for 7 days. After 7 days, Terrine-1 was thawed and then heated up in microwave for 2 min (Sample-1), while Terrine-2 was thawed and then boiled in water for 5 min (Sample-2). Viable bacterial count, chemical composition, pH, salinity, hardness, TBA, free amino acid content, and sensory evaluation were measured for both Sample-1 and Sample-2. Especially, the scores of sensory evaluation of Sample-2 is slightly higher than that of Sample-1. On the other hand, there were no significant differences on color, odor, taste, texture, and overall acceptance between Sample-1 and Sample-2.