• The Journal of Fisheries Business Administration
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• v.41 no.2
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• pp.25-44
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• 2010

The laver has been cultivated long time ago in Korea. And traditional production system was changed to new system about 30 years ago. The new production system is understood the specialization of laver products, that is, originally individual fishery households made final laver products from raw cultured laver in sea working to dry working in land, but the new system was separated raw laver production in sea and dry laver production, which made final dry laver products by purchase the raw laver in land. This change has been increased laver production, 10 billion sheets in 2000's from 5 billion sheets in 1980's. And rapid production increase gave rise to some troubles on laver industry that is a serious drop in real laver prices, discord structure between raw laver producer and dry laver producer, stagnation of laver consumption, etc. Now Korea is the best laver production country together with Japan in world. Then we have to consider some schemes for the sustainable development of laver industry. One of such schemes is export enlargement of laver against world. The consumption of laver has been globally increased in recent. The other is the grading test problem of dry laver. Because the rapid increase of laver production caused to drop laver quality. Then we seriously have to consider the grading test of dry laver for high level quality production.

• Preventive Nutrition and Food Science
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• v.19 no.1
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• pp.40-48
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• 2014

Laver is one of the most consumed edible red algae seaweeds in the genus Porphyra. Laver is primarily prepared in the form of dried, roasted, and seasoned products. We investigated the total polyphenol and flavonoid contents of laver products, and evaluated the in vitro antioxidant properties of solvent extracts from commercially processed laver products. Significant differences in the concentration of phenolic compounds were found among differently processed laver. The total phenolic content for laver extracts ranged from 10.81 mg gallic acid equivalent (GAE)/g extract to 32.14 mg GAE/g extract, depending on extraction solvent and temperature. Laver extracts contained very few flavonoids (0.55 mg catechin equivalent/g extracts to 1.75 mg catechin equivalent/g extracts). 2,2-Diphenyl-1-picrylhydrazyl (DPPH), 2,2'-azino-bis-3-ethylbenzothiazoline-6-sulphonic acid (ABTS), hydroxyl radical, and superoxide anion scavenging assays were used to determine the radical scavenging capacities of laver extracts. These assays revealed that the processing method and extraction condition affected the antioxidant potentials of laver. Antioxidant activity of dried laver, roasted laver, and seasoned laver increased in a concentration-dependent manner ($100{\sim}1,000{\mu}g/mL$). The radical scavenging activities of $37^{\circ}C$ and $100^{\circ}C$ water extracts were lower than that of a $37^{\circ}C$ 70% ethanol extract. The highest radical scavenging capacity was observed in the $37^{\circ}C$ 70% ethanol extracts of dried laver, roasted laver, and seasoned laver. Overall, these results support that notion that laver contains bioactive compounds, such as polyphenols and flavonoids, which may have a positive effect on health.

• Journal of the East Asian Society of Dietary Life
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• v.13 no.4
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• pp.326-333
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• 2003

The purpose of this study was to investigate the effect of various cooking methods(roasted, salad, deep-fried seasoned-roasted and commercial laver) on mineral contents, color and sensory evaluation of laver. The contents of mineral of dried laver by various cooking methods were analyzed using the Inductively Coupled Plasma(ICP) system. The results were summarized as follows : The content of crude protein, moisture, ash and crude fat in dried laver were 35.1％, 10.6％, 9.7％ and 0.8％, respectively. Among the minerals of dried laver, the content of poassium was the highest (2268.0mg/100g d.w.) and those of calcium and iron were comparatively high (495.1mg/100g, 13.5mg/100g). Ca/P ratio of dried laver was about 1:1 levels. Among various laver dishes, the total mineral content was the highest in the roasted laver, but low in the deep-fried laver. Among color values by cooking methods, "L(lightness)" and " - a(greenness)" values were the highest in the roasted laver, and "b(yellowness)" was the highest in the deep-fried laver. The seasoned-roasted laver was highly scored by the sensory evaluation.

• Korean journal of food and cookery science
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• v.24 no.1
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• pp.99-105
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• 2008

Laver-wrapped rice and laver-wrapped rice containing a vinegar blend (vinegar:sugar:water:salt = 5:2:2:1) were prepared and their degrees of aging from 10 to $30^{\circ}C$, total cell numbers, and total coliforms were examined and compared. The total cell numbers of the laver-wrapped rice increased to 1 log cfu/g at 36 hours, and the total cell numbers of the laver-wrapped rice with vinegar had increased to within 48 hours. At $20^{\circ}C$ for 24 hrs, the total cell numbers for the laver-wrapped rice had increased to 5 log cfu/g: whereas trhe total cell numbers of the laver-wrapped rice with vinegar(5ml of vinegar marinade mixed into 100g of steamed rice), stored at the same conditions had not increased. In the vinegar-marinated rice (2ml/100g rice), microorganisms appeared at 18 hours. However, at the concentration of 5ml/l00g of rice, microorganisms were not observed at 24 hours. Coliforms did not appear in the laver-wrapped rice nor in the laver-wrapped rice with vinegar(prepared at 10ml/100g) until 48 hours. When stored at 10 and $20^{\circ}C$, no microorganisms were found in the laver-wrapped rice with vinegar until 48 hours, respectively. However, at $30^{\circ}C$, microorganisms were observed in the laver-wrapped rice from 24 hours, and from 48 hours in the laver-wrapped rice with vinegar. These results suggest that laver-wrapped rice should be consumed within one day. The number of microorganisms inside the laver-wrapped rice reached 6 log cfu/g by 24 hours, but the increase in the laver-wrapped rice with vinegar was slower. The aging(% damaged starch) of the laver-wrapped rice with vinegar(5ml/100g the rice) stored at $20^{\circ}C$ was reduced, with 3% damaged starch at 24 hours. Consumer evaluations revealed that the laver-wrapped rice prepared with 5ml of the vinegar blend received higher scores for flavor, taste, texture, and overall acceptance as compared to the control. In particular, significantly higher scores were given for taste, texture, and overall acceptability. In summary, the laver-wrapped rice with vinegar had an extended shelf-life(more than 1 day) at storage temperatures of $20-30^{\circ}C$, as well as reduced retrogradation. In addition, based on consumer evaluations, adding vinegar to laver-wrapped rice laver is effective for increasing overall acceptability.

• The Journal of Fisheries Business Administration
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• v.42 no.2
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• pp.113-130
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• 2011

The laver has been cultivated long time ago by Korea and Japan. Korean Laver Industry has been influenced by Japan on the many factors since 20th. Nevertheless now the both country showed widening disparities across the aspect of total Laver Industry each other. The development steps of Korea and Japan Laver Industry have been advanced differently. That is, we can keep the Laver Industry development steps of both countries separate by 4 steps. But insignificant of every step against both countries has been dissimilar. We can separate from 4 steps in Korea, 1 step is origin period from beginning of laver cultivation to 1961. Next step is First Development period from 1962 to 1978. This period come out production increase from about 10,000 tons early 1960 to 50,000 tons late 1970. Next step is Second Development period from 1979 to 2000. This period come out eminent production increase from about 50,000 tons early 1980 to 200,000 tons late 1990. Next step is Stabilization period from 2001 to now. This period come out production control the size of its production and enlargement of Laver Export. We can also separate from 4 steps in Japan, 1 step is origin period from beginning of laver cultivation to 1944. Next step is Development period from 1945 to 1975. This period come out production increase from about 4 billion sheets early 1960 to 8.5 billion sheets 1975. Next step is Peak period from 1976 to 1982. This period come out sustainable production peak by 6~8 billion sheets and high price. Next step is Decline period from 1983 to now. This period come out production control the size of its production and sustainable price down. These differences showed out facing problems of Korean and Japanese Laver Industry differently. In case of Korea, the facing problems show out 3. First is structural problem, for example, trouble between original laver producer and the finished producer by dry laver products. Second is Insufficiency of Plants Protection System. Third is low quality of Laver. In case of Japan, the facing problems also show out 3. First is sustainable decrease of laver consumption. Second is change of mind against laver, for example, the change of the propensity to consume, and decrease of brand power. Third is Influence of global system. The difference of development steps of Korea and Japan Laver Industry show out 2 point of view to us. First we need consider positive strategy against laver production system of enlargement. Second, we need consider separate strategy against high quality laver and low quality laver.

• The Journal of Fisheries Business Administration
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• v.40 no.3
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• pp.147-167
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• 2009

The objective of this study is to analyze the determinants of at-home laver consumption expenditures using the data from a survey of households implemented in 2009. It happened that non-response ratios of monthly expenditures on dry laver and flavored laver among sampled households are 18.8% and 25.6%. Accordingly, this study tries to analyze the determinants affecting at-home laver consumption expenditures by using type II tobit model, one of sample selection models, to deal with sample selection bias caused from non-response data. Analysis results show the age variable positively affects expenditures on dry laver but negatively contributes to expenditures on flavored laver. In addition, the household size, the household's income, the degree of preference for laver have positive relationships with both expenditures. Household size elasticity and income elasticity of the expenditure on dry laver are estimated as 0.220 and 0.251. In the case of flavored laver, these elasticities are estimated as 0.484 and 0.261. Such analysis results can provide information on division of the at-home laver consumption market into groups with high willingness to expense and implementation of detailed marketing strategies to increase at-home laver consumption. The methodology of this study can be applied to consumer preference analysis on other marine products and other analyses on sample with non-response data in the fishery research.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.56 no.1
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• pp.45-54
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• 2020

In this study, an automatic system for improving the working environment and increasing production efficiency of a laver aquaculture industry in Korea was developed by combining a hydraulic control system and a load cell in a current landing work of the laver. The improved gathering laver system allowed the automatic gathering process of the laver in the sea with the hydraulic control system connected to a cutting machine of the laver on the operating ship, which has been used for gathering the laver semi-automatically in a form of the traditional farming method. The transporting process of the laver from an operating ship to the land was improved as follows. A frame installed on the operating ship and the bag nets were designed and made to hold about 1,000 kg of the laver inside. The bag nets contain the laver on the improved operating ship were tied in knots and hooked on a crane using a load cell. The weight is measured immediately by lifting the bag nets through the load cell system. Weight information is communicated to the fishermen and successful bidders through the application. The advantages of the improved system can help fishermen to fish by improving their working environment and increasing production efficiency. The field survey to improve the landing operation of the laver aquaculture was conducted in Gangjin, Goheung, Shinan, Wando, Jindo, and Haenam in South Jeonnam Province. A total of 10 sites including Gunsan in Jeonbuk Province, Daebu Island in Ansan City, Jebu Island in Hwaseong City in Gyeonggi Province, and Seocheon in Chungnam Province were searched to collect data. Prototypes of the system were tested at the auction house of laver located in Goheung, where laver collection using hydraulic control and landing using road cell could be improved.

• Korean journal of food and cookery science
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• v.26 no.1
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• pp.54-61
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• 2010

This study was performed to determine the optimal manufacturing conditions adding green laver, which has a rich aroma and unique taste, to Sulgidduk. The variables in green laver Sulgidduk production were amounts of green laver powder and water. Six sensory characteristics were used for sensory evaluations, including color, green laver flavor, green laver taste, moistness, softness, and elasticity. The optimal amounts of the powder and water were found to be 6.84 g for green laver powder and 31.08 g for water, satisfying a target sensory score (7.0/9.0) according to a response surface method. Sulgidduk with these optimal amounts of green laver and water was tasted by 118 consumers and showed a high acceptability score (6.94). Older consumers ($\geq$30 years old) preferred the color and flavor of green laver significantly more than younger consumers ($\leq$29 years old) did (p<0.01). Color analysis results of green laver Sulgidduk were significantly different in brightness, redness, and yellowness from those of Sulgidduk (control)(p<0.01). Texture analysis scores of green laver Sulgidduk were significantly lower than those of Sulgidduk (control) in hardness, adhesiveness, springiness, cohesiveness, gumminess, and chewiness, and they were significantly different in adhesiveness and chewiness (p<0.05).

• Journal of the East Asian Society of Dietary Life
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• v.25 no.1
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• pp.146-152
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• 2015

Seasoned laver is the highest consumed item among processed laver foods. However, it easily undergoes quality deterioration during processing and storage by lipid oxidation. The purpose of this study was to develop onion seasoned laver with strengthened functional properties through evaluation of storage characteristics. Proximate composition, color index, acid value, thiobarbituric acid (TBA) production, and sensory evaluation of seasoned laver with 0, 15 and 30% onion powder were analyzed during storage periods of 0, 12 and 24 weeks. The lightness, redness, and yellowness of 30% onion seasoned laver significantly increased according to storage period. The acid value and TBA production significantly increased in control laver without onion powder, with no significant difference in 30% onion seasoned laver according to storage period. Sensory preference of onion seasoned laver was better than that of control laver in terms of taste, texture, and overall acceptability. To sum up these results, seasoned laver with 30% onion powder showed superior color degree, acid value, TBA production and sensory preference in proportion to added amount.

• Journal of the Korean Society of Food Culture
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• v.29 no.5
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• pp.421-427
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• 2014

This study was conducted to promote the utilization of fish paste added with green laver powder as a food product. The tested concentrations of green laver powder were 0, 3, 5, and 7%. The pH of the samples ranged from 6.71 to 6.90, and moisture content ranged from 70.03 to 70.57%. The L and a values of the samples decreased as the concentration of green laver powder increased and b value increased. Folding test in all test samples showed AA that mean good flexibility. In the texture meter test, hardness, cohesiveness, and springiness increased according to increasing concentration of green laver powder. However, gumminess and brittleness of the fish paste decreased upon addition of green laver powder. In the sensory evaluation, fish paste prepared with 5% green laver powder was preferred over other fish pastes. These results suggest that green laver powder can be applied to fish paste for the purpose of high quality and functionality.