• Korean Journal of Fisheries and Aquatic Sciences
• /
• v.41 no.6
• /
• pp.419-426
• /
• 2008

Physicochemical characteristics of gelatin extracted from abdominal skin of yellowfin tuna (Thunnus albacares), were investigated by comparing its proximate composition, pH, amino acid composition, viscoelastic properties, gel strength and SDS-PAGE patterns, with those of bovine and porcine gelatins. The effects of gelatin concentration, maturation time, heat and freeze treatments on the gel strength of yellowfin tuna abdominal skin gelatin were studied. Amounts of $\alpha$-chains, $\beta$- and $\gamma$-components of yellowfin tuna abdominal skin gelatin were higher than those of the two mammailan gelatins. Yellowfin tuna abdominal skin gelatin had the lowest imino acids (proline and hydroxyproline) content, which was consistent with that of other fishes. However, yellowfin tuna abdominal skin gelatin was highest in glycine, alanine, and lysine. The gel strengths of all gelatins were proportional to the concentration of gelatin, but yellowfin tuna abdominal skin gelatin exhibited the greatest gel strength at each concentration. Yellowfin tuna abdominal skin gelatin required a longer maturation time than the two mammalian gelatins to form a firm gel. Higher heating temperature decreased the gel strength of yellow fin tuna abdominal skin gelatin more than in the two mammalian gelatins. Freezing decreased the gel strength of bovine gelatin only slightly, but longer freezing times resulted in greater reductions in gel strength in the yellowfin tuna abdominal skin and porcine gelatins.

• Korean Journal of Fisheries and Aquatic Sciences
• /
• v.48 no.6
• /
• pp.833-838
• /
• 2015

To develop a value-added product from individually quick-frozen oyster Crassostrea gigas extract (IQFOE), we prepared two types of oyster sauce (OS): bottled OS (BOS) and retort pouched OS (ROS). We investigated processing conditions, quality metrics and flavor compounds in each type of sauce. We found that the most appropriate base formular for both BOS and ROS consisted of 40.0% IQFOE (Brix $30^{\circ}$), 15.0% sugar, 6.0% salt, 4.0% monosodium glutamate, 4.0% soy sauce, 3.5% starch, 3.0% yeast extract, 3.5% wheat flour and 21.0% water. The crude protein, salinity and amino-nitrogen contents of the BOS and ROS were 8.2 and 8.3%, 9.3 and 9.2%, and 539.2 and 535.2 mg/100 g, respectively. In commercial oyster sauces (COS), these values were 4.7-6.5%, 9.7-12.0%, and 244.7-504.2 mg/100 g, respectively. The total free amino acids content of ROS was 7,346.9 mg/100 g, and the main free amino acids were glutamic acid, taurine, proline, glycine and alanine. The inosinic monophosphate (IMP) content of the ROS was 131.6 mg/100 g, and the primary inorganic ions were Na, K, S and P. The present BOS and ROS have favorable organoleptic qualities and storage stability compared with COS, and are suitable for commercialization as high-flavor seasoning sauces.

• Korean Journal of Fisheries and Aquatic Sciences
• /
• v.45 no.5
• /
• pp.445-453
• /
• 2012

This study examined microbial contamination during seasoned and dried squid Dosidicus gigas processing, including the apparatus, machines, and employee's gloves at each step in processing at two companies. The numbers of bacteria floating in air in each processing area were also examined. The numbers of Staphylococcus aureus (3.6-6.0 log CFU/g) and Escherichia coli (1.3-1.4 log MPN/100 g) in domestic and imported daruma (a semi-processed product of seasoned and dried squid) at companies A and B exceeded the regulatory limits of the Food Sanitary Law of Korea (S. aureus, ${\leq}2.0$ log CFU/g; E. coli, negative). S. aureus in both daruma was reduced to below the detection limit or 3.6 log CFU/g after the roasting step, but increased again to 3.3 and 5.5 log CFU/g after the mechanical tearing step at companies A and B, respectively. E. coli showed similar tendencies at both companies. The surfaces of the apparatus, machines, and employee's gloves that contacted daruma were also contaminated with S. aureus (1.0-5.5 log CFU/$m^2$) and E. coli (negative-to 3.5 log MPN/$m^2$). The numbers of bacteria floating in air were high (1.7-5.1 log CFU/$m^3$) at both companies. These results suggest that sanitation standard operating procedures (SSOP) must be developed to control of microbial cintamination in seasoned and dried squid.

• The Plant Pathology Journal
• /
• v.29 no.1
• /
• pp.67-76
• /
• 2013

A chitinolytic bacterial strain having strong antifungal activity was isolated and identified as Burkholderia cepacia MPC-7 based on 16S rRNA gene analysis. MPC-7 solubilized insoluble phosphorous in hydroxyapatite agar media. It produced gluconic acid and 2-keto-gluconic acid related to the decrease in pH of broth culture. The antagonist produced benzoic acid (BA) and phenylacetic acid (PA). The authentic compounds, BA and PA, showed a broad spectrum of antimicrobial activity against yeast, several bacterial and fungal pathogens in vitro. To demonstrate the biocontrol efficiency of MPC-7 on late blight disease caused by Phyto-phthora capsici, pepper plants in pot trials were treated with modified medium only (M), M plus zoospore inoculation (MP), MPC-7 cultured broth (B) and B plus zoospore inoculation (BP). With the sudden increase in root mortality, plants in MP wilted as early as five days after pathogen inoculation. However, plant in BP did not show any symptom of wilting until five days. Root mortality in BP was markedly reduced for as much as 50%. Plants in B had higher dry weight, P concentration in root, and larger leaf area compared to those in M and MP. These results suggested that B. cepacia MPC-7 should be considered as a candidate for the biological fertilizer as well as antimicrobial agent for pepper plants.

• Korean Journal of Fisheries and Aquatic Sciences
• /
• v.44 no.6
• /
• pp.635-643
• /
• 2011

Agar was prepared from Gelidium amansii collected from Jeju Island, South Korea. This agar preparation has high gel strength and low sulfate content compared with G. amansii agar from Morocco. Accordingly, agarose was made from the Jeju agar through the consecutive refining processes of dimethyl sulfoxide (DMSO) extraction and ethylene diamine tetra acetic acid (EDTA) washing. The physicochemical properties of the resulting agarose were compared with those from agarose prepared using only DMSO extraction. Consecutive DMSO extraction and EDTA washing more strongly affected the physicochemical properties of the agarose (purified agarose) compared with the use of DMSO extraction alone. These properties were similar to those of commercial agarose used for electrophoresis. In DNA electrophoresis, the separation and movement speed of the purified agarose were similar to those of the commercial agarose. In a $^{13}C$ NMR analysis, the purified agarose exhibited the same carbon peak as the commercial agarose. When observed under scanning electron microscopy, the agar had an even and smooth surface without irregularities or pores, and the purified agarose had a wide surface area with a large number of pores; the commercial agarose had an irregular surface that would allow the solvent to easily permeate. These results illustrate that the physicochemical properties of agarose prepared from DMSO extraction and EDTA washing were more effective than those observed after DMSO extraction alone; thus, these processes used in succession will be useful in agarose industries.

• Korean Journal of Fisheries and Aquatic Sciences
• /
• v.49 no.6
• /
• pp.766-771
• /
• 2016

The pacific oyster Crassostrea gigas has a desirable taste and flavor that differs from those of other fish and shellfish. In order to develop a high value-added product from individually quick-frozen oyster extract (IQFOE), we prepared an oyster granular flavor seasoning (OGS) from IQFOE and characterized its qualities. The OGS was prepared by granular molding and fluidized bed drying with inosine monophosphate (IMP, 0.1%), yeast extract powder (1.4%), tangle extract powder (0.6%), monosodium glutamate (MSG, 5.0%), microcrystalline cellulose (0.6%), lactose (27.5%), salt (33.0%), spray-dried IQFOE (22.5%) as a powdered materials, and IQFOE ($Brix\;25^{\circ}$, 7.0%), soy sauce (0.4%) and water (1.7%) as a liquid materials. The moisture, crude protein, pH and salinity of the OGS were 3.4%, 12.5%, 6.50 and 32.0%, respectively. Especially, the OGS revealed very higher amino-N content (1,856.0 mg/100 g) than that (1,291.2-1,610.2 mg/100 g) of other commercial flavor seasonings. In taste-active compounds, free amino acid contents was 1,359.0 mg/100 g, and major ones were glutamic acid, taurine, hydroxyproline, glycine, lysine, phosphoserine, proline in order. And OGS showed good organoleptic qualities for taste, odor and general preference compared with commercial flavor seasonings on a local market.

• Korean Journal of Fisheries and Aquatic Sciences
• /
• v.49 no.6
• /
• pp.772-778
• /
• 2016

To develop a value-added product from individually quick-frozen oysters Crassostrea gigas (IQFO), we prepared a retort pouched oyster soup (RPOS) from IQFOs and characterized its processing conditions and quality metrics. We found that the most appropriate manufacturing process for the RPOS consisted of half-thawing and washing raw IQF oysters, blanching, adding them to the retort pouch along with other ingredients (base soup stock, IQF oyster extract, radish, bean sprouts, garlic, and red pepper), sealing, retort sterilization ($120^{\circ}$, F0-value 10 min.), cooling, and packaging inspection. The moisture, crude protein, pH and salinity of the RPOS were 91.0%, 2.8%, 6.20 and 0.9%, respectively. The total amino acid content of the RPOS was 2,163.8 mg/100 g, and the main amino acids were glutamic acid, aspartic acid, leucine, proline, lysine and arginine. The primary inorganic ions were Na, K, S and Zn. In taste compounds, total free amino acid content was 313.4 mg/100 g, and the main free amino acids were glutamic acid, taurine, proline, hydroxyproline, aspartic acid, glycine, alanine, valine, lysine and arginine. This RPOS has good storage stability and organoleptic qualities compared with commercial retort pouched shellfish soup, and is suitable for commercialization as a value-added instant seafood soup.

• Korean Journal of Plant Resources
• /
• v.24 no.6
• /
• pp.724-728
• /
• 2011

With both common and Tartary buckwheat species, this study was aimed at producing new commercially useful bio-materials with higher nutritional and medicinal value due to higher components for health promotion and diseases care. In common buckwheat sprouts, it was found that root length at $20^{\circ}C$ was longer (5.93 cm) than at 25 and $30^{\circ}C$, whereas the hypocotyls length, fresh weight of each sprout, and whole fresh weight showed the highest value at $30^{\circ}C$. For Tartary buckwheat, the root length, hypocotyl length and fresh weight of each sprout and whole fresh weight were also the highest at $30^{\circ}C$. Common buckwheat (Suwon No.1) and Tartary buckwheat (KW45) sprouts cultured at $20^{\circ}C$ showed that hypocotyl length, fresh weight of each sprout, and whole fresh weight in the control were higher than those sprouts treated with 5% and 10% deep sea water (DSW), while the sprouts cultured at $30^{\circ}C$ showed were significantly longer hypocotyls than the control or 5% DSW treatment.

• Journal of the Korea Society of Computer and Information
• /
• v.26 no.10
• /
• pp.167-172
• /
• 2021

After the Ferry Sewol accident, public interest in marine safety has increased. However, as the marine leisure tourism population increases, the number of casualties caused by marine accidents is increasing, so marine safety education is urgently needed. Since facilities related to marine safety education in Korea are geographically biased to the west, regional imbalances in education are significant. Therefore, this study suggested solutions to the problems of developing educational contents and securing budgets and professionals by using idle facilities of the Korea Institute of Maritime and Fisheries Technology(KIMFT) located in Busan as a maritime safety education center. In addition, as a result of estimating demand using the gravity model, it was estimated that the demand would range from 150,000 to 130,000 per year. This study sufficiently proved social policy validity for policy suggestions using existing idle sites as maritime safety education centers based on objective verification methods and is expected to contribute substantially to policy promotion in the future.

• Korean Journal of Fisheries and Aquatic Sciences
• /
• v.55 no.3
• /
• pp.267-277
• /
• 2022

This study investigated changes in the physicochemical and microbiological properties of fermented fish sauces based on the pacific sand lance Ammodytes personatus during fermentation according to rice koji treatments and salt contents. In total, six fish sauces were prepared, with rice koji treatment for 24 or 72 h before salt addition, and salt contents of 10 or 20%, including two controls to compare the response to different salt contents without koji treatment. The initial pH values of the sauces with koji treatments were notably lower than those of the controls. Over the 10 months of fermentation, the amino nitrogen contents of the sauces with 10% salt were higher than those with 20% salt, while the volatile base nitrogen value was also increased. In the microbial community, the initial numbers of lactic acid bacteria and mold were higher in the sauces with koji treatment than in the controls. After 8 months of fermentation, the free amino acid and organic acid contents were higher in the sauces with koji treatment than in the controls. Although the fermentation rate was affected to a greater extent by salt contents, the rice koji treatment also exerted a positive effect on the acceleration of fermentation.