• Korean Journal of Fisheries and Aquatic Sciences
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• v.20 no.5
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• pp.469-475
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• 1987

The present paper was investigated to elucidate the nitrite-scavenging ability of seaweed extracts. Seaweed extracts possessed the scavenging ability of nitrite. By fractionation of seaweed extracts, nitrite-scavenging ability of laver(Porphyra tenera), sea lettuce(Enteromorpha compresa) extracts were effective in the water-soluble fraction, but sea mustard (Undaria pinnatifida), sea staghorn (Codium fragile) extracts in the methanol-soluble fraction. Nitrite scavenging ability of seaweed extracts was also pH-dependent, highest at pH1.2 and lowest at pH6.0. Particularly, nitrite-scavenging abilities of water-soluble fractions obtained from laver and sea lettuce were similar to that of L-ascorbic acid at pHl.2. After seaweed extracts were treated with sodium borohydride, nitrite-scavenging ability was remarkably decreased at pH1.2. It is assumed that reducing powers of seaweed extracts participated in their nitrite-scavenging abilities.

• Korean Journal of Food Science and Technology
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• v.43 no.1
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• pp.30-38
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• 2011

Effects of depolymerization treatments of a carbohydrase mixture (CM), ultrasound, and irradiation on the physical properties of defatted mustard meal-based edible films (DMM films) were investigated. DMM hydrocolloids were added to CM (0.42% (w/w solution)), treated by ultrasound (500-700 W, 10-30 min) or ${\gamma}$-ray (40-100 kGy) to prepare film-forming solutions. Films were formed by drying. The CM treatment at 0.42% (w/w), pH 5.5, and 40-$50^{\circ}C$ with a 0.5 hr incubation time resulted in the highest colloidal stability in the film-forming solution. The depolymerization treatments did not dramatically change the water vapor permeability of the films. The solubility of the film decreased up to 53.1% by the CM treatment. The ultrasound treatment (700 W-30 min) decreased tensile strength and elongation. The ultrasound treatment (600 W-20 min) resulted in more compact and uniform structures of the films. Flavor profiles were differentiated by the power level and the time of the ultrasound treatment.

• Korean Journal of Food Science and Technology
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• v.53 no.5
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• pp.634-639
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• 2021

This study investigated the effects of cold plasma (CP) treatment on the properties of biopolymer films prepared with defatted mustard meal (DMM films). CP treatments using N₂, O₂, He, Ar, and dry air did not affect the tensile properties, water vapor permeability, color, and morphology of DMM films, whereas the treatments using He and Ar improved their printability. The tensile strength (TS) of O₂- or air-CP-treated DMM films and the elastic modulus (EM) of O₂-, He-, Ar-, or air-CP-treated films were lower than those of the untreated films. An increase in the power of Ar-CP treatment resulted in an increase in EM. The optimum treatment power and time for minimizing yellowness changes by Ar-CP treatment were 420 W and 40 min, respectively. The results demonstrated the potential application of CP treatment to improve the film properties of DMM films and possibly other agricultural by-product-based biopolymer films, making the films more applicable to food packaging.

• Journal of Marine Bioscience and Biotechnology
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• v.2 no.3
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• pp.133-141
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• 2007

There are produced more than 600,000 tons of seaweeds every year along the coast of the Korea. Jeonnam province, south-west coast area, of Korea is producing 93% of total amounts of seaweeds. The laver, sea mustard, and tangleweed maintain stability in the output and has been exported as a simple product processing through drying or salting. It was evaluated the low value-added products and limited the expansion for the consumption of seaweeds. The seaweeds contains 40-60% carbohydrate and structurally different compared with land plant. The dietary fiber from seaweeds has been known the function of facilitating the bowl movement, excretion the heavy metal in the body, lowering the blood cholesterol level, anti-coagulant of blood, and anticancer. Especially, brown algae including sea mustard, seaweed fusiforme, and tangleweed contains alginic acid, laminarin, mannitol, fucoidan which are lowering the blood cholesterol level, lowering blood pressure, and fusion of blood clot. Agar-agar, carrageenan, and porphyran compound in red algae are known to antimutagenicity and anticoagulant function. In spite of potential of seaweed as a main bio-resource, there are lack of research to facilitate the consumption with its functional properties and consumers are unsatisfied with simple processing products. Also, the seaweed by-product dump into the sea and cause pollution of the seawater. Therefore, there are needed the scheme to promote the consumption of seaweeds. The development of value-added products, finding functional properties from seaweeds, development the functional feed for animal using seaweed by-products, and utilization of unused algae for food or other industrial uses will increase fisherman's income as well as serve as an aid for the people health due to its functional properties. Using by-product of seaweed and unexploited seaweed are needed to development of bio-degradable food packaging material and functional feed for animal.

• Journal of Environmental Science International
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• v.12 no.7
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• pp.735-744
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• 2003

The field observations on a seasonal characteristic of organic matter and its origin in the surface sediment were carried out at 35 stations in Deukryang bay, southern coast of Korean Peninsula from May 1995 to February 1996. The analytical parameters were mud temperature, ignition loss(IL), chemical oxygen demand(COD), pheopigment, sulfide and water content. The origin and seasonal dynamics of organic matter in Deukryang Bay were analyzed by COD/IL, COD/sulfide ratio and principal component analysis(PCA). As a results of the mud temperature fluctuated between 2.1$^{\circ}C$ with the lowest mean 4.6$^{\circ}C$ in winter and 27.6$^{\circ}C$ with the highest mean 25.5$^{\circ}C$ in summer. The range of ignition loss(IL) was from 3.1% in autumn to 21.5% in winter. Chemical oxygen demand(COD) showed the highest mean value of 8.45 mg/g dry in spring within the range of 2.90∼18.21 mg/g dry, while it showed the lowest value of 4.33 mg/g dry in autumn within the range of 0.67∼10.37 mg/g dry. Pheopigments showed the highest mean value of 9.04 $\mu\textrm{g}$/g dry in autumn within the range of 1.36∼20.44 $\mu\textrm{g}$/g dry, while it did the lowest mean value of 2.20 $\mu\textrm{g}$/g dry in summer within the range of 0.33∼11.36 $\mu\textrm{g}$/g dry. The range of total sulfide (H$_2$S) was from no detect(ND) to 3.30 mg/g dry in spring. And water content showed the annual mean value of 43.6% within the range of 23.6∼54.9%. The source of organic matter by COD/IL and COD/sulfide ratio in Deukryang Bay had been producted by primary producer in sea water areas except the areas effected by small stream, domestic and animal wastes. And the analytical results of PCA was able to be divided into three different regions. The former was characterized by the shallow depth and authigenic organic matter from phytoplankton in northwest area and northeastern inner bay, the secondary was done by deeper depth and allochthonous one from lands in southeast area and eastern entrance of bay, and the latter was done by authigenic one from the farm of seaweeds such as, sea cabbage, sea mustard etc in western entrance of bay. But a study on the relationship between sulfide and COD concentration in the northeastern inner bay which was characterized by the water stagnation will to take much more studying including major constituents of organic matter in the future.

• The Korean Journal of Food And Nutrition
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• v.15 no.3
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• pp.257-266
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• 2002

The purpose of this study is screening of microfloras involved in hydrolysis of seaweed tenella, seaweed fusiforme and green laver. This is a part of studies on the hydrolysis of seaweed using microorganisms. First, about two hundred microflora samples were obtained from mountain, rice field, dry field, sea, seaside and fish market in the vicinity of Yeosu. Thirty-three microflora samples were screened from the destruction of tissue in sea tangle and sea mustard. It was sufficient that results of the naked eye observation were obtained at eight microflora samples as a feces of bull, a decayed pine tree, a soil of dry field, the mud of the banks in a rice field, the water of a ditch in a rice field, the weed of the banks in a rice field, the water in a rice field and leaved in the air. Above all, extraction rate and contents of reducing sugar in extracts of seaweeds added a decayed pine tree(sample No. 8) and the water of a ditch in a rice field(sample No. 27) were showed high value. And the value of chemical analysis of the sample is much better in comparison with control. Accordingly the hydrolysis of seaweed using microorganisms in the inside of these microflora samples can be possible.

• The Korean Journal of Malacology
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• v.29 no.3
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• pp.189-195
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• 2013

Experiments for net cage culture at sea were conducted in each $2.4{\times}2.4$ m in area and took the samples from four different densities: 150, 300, 450 and 600 per cross-sectional area ($m^2$) of shelter. The same stocking densities applied to indoor tank culture to investigate the growth and survival rate. The size of juvenile abalone sample was $36.14{\pm}2.28$ mm for net cage culture and $38.62{\pm}3.22$ mm or indoor tank. Feed such as raw brown sea mustard, raw kelp and dried kelp was sufficiently provided to the abalone. In net cage culture experiment, the growth of the spat of juvenile abalone was the fastest $60.53{\pm}5.75$ mm in the 150 abalone cage per square meter ($m^2$), followed by the 300 abalone cage at $54.01{\pm}5.17$ mm, 450 abalone cage at $51.48{\pm}5.37$ mm and 600 abalone cage at $51.09{\pm}4.96$ mm in order. In the meantime, in the indoor tank experiment, the 150 abalone indoor tank was the fastest $47.50{\pm}6.31$ mm per square meter, followed by the 300 abalone tank at $45.92{\pm}5.23$ mm, the 450 abalone tank at $44.24{\pm}5.59$ mm and the 600 abalone tank at $43.62{\pm}4.44$ mm in order. The survival rate was more than 97.9% in all the experiments, not showing a significant difference.

• Journal of the Korean Society of Food Science and Nutrition
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• v.33 no.3
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• pp.598-602
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• 2004

In the preparation of jam using Undaria pinnatifida sporophyll, effects of food ingredients to the jam rheology were investigated. The paste was prepared by crushing the sporophyll using chopper and homogenizer with 2.5 times water and then it was filtrated before to make a jam. The sporophyll jam was adjusted to 62$^{\circ}$Brix by heating and concentration. It was a similar to the commercial jam in the gel strength. Among the various treatments, the jam prepared with 60% (w/w) sugar, 0.75% (w/w) high methoxy (HM) pectin and 0.3% (w/w) citric acid showed best quality aspects of both texture profile analysis (TPA) and sensory evaluation. Addition of 0,08% (v/w) synthetic strawberry flavor and 0.5% (w/w) cinnamon powder to sporophyll paste gave a good masking effect for the undesirable sea mustard flavor.

• Korean journal of food and cookery science
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• v.25 no.2
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• pp.189-198
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• 2009

This study was conducted to analyse middle school students' perceptions of seafood as well as their eating experiences and favorite cooking methods for seafood. It also examined the frequency and use of seafood on school lunch menus. Questionnaires were distributed to 739 students in 5 middle schools in the Busan area. On a scale of 5.00, the average scores for perceptions toward seafood were as follows: 3.67 for health & nutrition, 3.53 for taste, 2.53 for smell, 2.77 for convenience. The male students had significantly_(p<0.05) higher perception scores for health & nutrition, taste, and smell than the female students. Among 38 types of seafoods, the highest percentages for eating experiences included seaweed_(99.2%), anchovies_(99.1%), fried fish paste_(98.6%), shrimp_(98.4%), crab_(98.2%), squid_(97.9%), sea mustard_(97.8%), mackerel_(97.7%), dried squid_(97.3%), and hair tail_(96.9%). However, the majority of students had eaten a limited amount of seafood. The degree of seafood intake at home was significantly_(p<0.01) higher than at school. The students' favorite cooking methods for seafood were in the order of grilling, stir-frying, steaming, deep-fat frying, and soup. However, the middle school lunch programs primarily served as soup, seasoning, stir-fried, braised, deep-fat fried, and grilled, respectively. The main reasons for leaving seafood on a plate were inconvenience due to the fishbones_(62.7%), tasteless_(45.4%), and disliking the smell_(35.7%). Improvements that students wanted for seafood on school lunch menus included removal of fishbone for convenience_(67.0%), taste_(52.0), and increased variety of seafood types_(38.2%).

• Journal of the Korean Dietetic Association
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• v.7 no.4
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• pp.361-372
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• 2001

This study was conducted to investigate the status of calcium intake and serum calcium level in perimenopausal women. The age distribution of the subjects was 49-55 years. Daily nutrient intake and dietary sources of calcium were analyzed by a convenient method and a food frequency questionnaire. At the same time, fasting blood samples were collected and serum calcium concentration was measured. The BMD of subjects was measured by Dual Energy X-ray Absorptiometry (DEXA). Fifty percent of the subjects under 50 years of age ($\leq$49 yr group) and 66.9% of the subjects from 50 years and up ($\geq$50 yr group) were classified as osteopenia or osteoporosis. Intake of energy (p<0.001), protein (p<0.05), fat (p<0.05), calcium (p<0.01) was significantly different between $\leq$49 yr group and $\geq$50 yr group. Mean daily intake of calcium was much lower than the Korean RDA : 94.9% in $\leq$49 yr group and 87.4% in $\geq$50 yr group. The average concentration of total calcium in serum was within the normal range in $\leq$49 yr group. Serum calcium concentrations were significantly (p<0.05) different between $\leq$49 yr group and $\geq$50 yr group. It was noteworthy that serum calcium concentration was positively related to the intake of protein, fat and calcium. Lettuce, sea mustard, bean-curd, anchovy, radish and perilla leaf was included among the major sources of dietary calcium. Further investigation is necessary to make sure of the relations between BMD and serum calcium level and calcium intake.