• Journal of the Korean Society of Food Culture
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• v.20 no.4
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• pp.446-450
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• 2005

Chemical compositions such as total sugar, sulfate/total sugar, protein and 3,6-anhydrogalactose content of porphyran extracted from commercial laver, discolored laver and laver waste were measured. The total sugar contents of commercial laver, discolored laver and laver waste showed 54.5%, 45.7% and 56.2%, respectively. The total sugar of the commercial laver and laver waste were showed almost similar portion although that of discolored laver showed relatively lower level. The sulfate/total sugar contents showed 17.6%, 13.9% and 17.3%, and 3,6-anhydrogalactose contents showed 13.8%, 9.1% and 13.9% in commercial laver, discoloredlaver and laver waste respectively.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.53 no.2
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• pp.156-164
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• 2020

To develop a seasoned laver from cooking oyster effluent (C-COE), this study optimized the C-COE concentration, roasting temperature and time using response surface methodology (RSM). The optimal C-COE concentration, roasting temperature and time for producing seasoned laver from C-COE were 31.0%, 182.2℃ and 21.1 sec, respectively. The proximate composition of the seasoned laver prepared with C-COE under the conditions was 5.2% moisture, 37.4% crude protein, 8.2% crude lipid, 11.1% ash, 38.1% carbohydrate. The water activity of the prototype seasoned laver was 0.038. The prototype had stronger taste and flavor intensities than a commercial product. There was no difference (P>0.05) in the Hunter color value between the prototype and the commercial product. The peroxide (POV) and acid values (AV) of the prototype were 6.0 meq/kg and 1.4 mg KOH/g, respectively, which are considered acceptable. The results suggest that the seasoned laver with C-COE developed can be industrialized.

• 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.

• The Korean Journal of Food And Nutrition
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• v.18 no.1
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• pp.11-18
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• 2005

Angiotensin Ⅰ converting enzyme(ACE) inhibitory activities of laver(Porphyra tenera) protein hydrolysates were investigated by enzymes used for hydrolysis, molecular fractions and drying methods. For the enzymatic hydrolysis, crude laver protein, separated by filtration of water extract of dried laver extracted with 20 times(w/v) water for 3 hours at boiling temperature, were hydrolyzed with three commercial protease, Pepsin, alcalase and maxazyme NNP at optimal conditions. The yield of hydrolysis and ACE inhibitory activities of which were high in order of pepsin, alcalase and maxazyme NNP. ACE inhibitory activities of laver hydrolysates by molecular levels were high in order of 3 kDa > 10 kDa > 3∼10 kDa, and the IC/sub 50/ ACE inhibitory activities by molecular lebels were 4 mg/mL(3 kDa), 5 mg/mL(total hydrolysate), and 20 mg/mL(10 kDa), respectively. The storage stability of dried laver hydrolysates at 20℃ were strongly affected by drying methods, hot air dried of which were much stabler than freeze-dried one.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.45 no.5
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• pp.454-459
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• 2012

To investigate heavy metals (Hg, Pb and Cd) and their potential health risks in commercial dried laver (Porphyra sp.), we collected 45 samples from the major production areas on the western and southern coasts of Korea (Hwaseong, Seocheon, Gunsan, Muan, Shinan, Jindo, Haenam, Wando, Jangheung, Goheung and Busan). The Hg, Pb and Cd concentrations were measured using inductively coupled plasma spectrometry (ICP-MS) or a mercury analyzer. The average Hg, Pb and Cd concentrations in the dried laver were $0.006{\pm}0.0017$, $0.196{\pm}0.0614$ and $0.894{\pm}0.4882$ mg/kg, respectively. Based on the 2007 Korean Public Nutrition Report, these levels are 0.02, 0.11 and 2.47% of the provisional tolerable weekly intake (PTWI) for Hg, Pb and Cd, respectively, established by the FAO/WHO. The hazard quotient (HQ) determined from the ratio of exposure and safe levels were less than 1.0. Therefore, the levels of overall exposure to Hg, Pb and Cd for dried laver were below the recommended JECFA (Joint FAO/WHO Expert Committee on Food Additives) levels, which indicate safe levels for public health.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.51 no.4
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• pp.362-368
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• 2018

There is increased consumer demand for roasted seasoned laver Pyropia yezoensis, processed in various ways. The antioxidative activity of roasted seasoned laver was evaluated at different storage times and the quality of the roasted seasoned laver was improved. The laver was also heated at different temperatures for 3 seconds: $340^{\circ}C$ (SH340), $345^{\circ}C$ (SH345), $350^{\circ}C$ (SH350) and commercial roasted seasoned laver (D) was used as standard. The samples were stored in a transparent acrylic case ($39{\times}27{\times}18cm$) at room temperature for 10 weeks. The total phenolic content began to decrease after 7 weeks of storage and was 395.2, 386.4, 395.8 and $416.4{\mu}g/100g$ for SH340, SH345, SH350 and D, respectively. The respective DPPH (1,1-diphenyl-2-picryl-hydrazyl) radical scavenging activity after 7 weeks of storage were 48.6%, 49.5%, 47.7% and 46.1%. The ferric reducing antioxidant power (FRAP) decreased rapidly after 7 weeks of storage due to the influence of sulfate groups. Therefore, the appropriate storage period and packaging method should be established based on these results.

• Preventive Nutrition and Food Science
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• v.18 no.2
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• pp.139-144
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• 2013

Laver, a red algae belonging to the genus Porphyra, is one of the most widely consumed edible seaweeds. The most popular commercial dried laver species, P. tenera and P. haitanensis, were collected from Korea and China, respectively, and evaluated for proximate composition, amino acids, minerals, trace heavy metals, and color. The moisture and ash contents of P. tenera and P. haitanensis ranged from 3.66~6.74% and 8.78~9.07%, respectively; crude lipid and protein contents were 1.96~2.25% and 32.16~36.88%, respectively. Dried lavers were found to be a good source of amino acids, such as asparagine, isoleucine, leucine, and taurine, and ${\gamma}$-aminobutyric acid. K, Ca, Mg, Na, P, I, Fe, and Se minerals were selected for analysis. A clear regional variation existed in the amino acid, mineral, and trace metal contents of lavers. Regular consumption of lavers may have heath benefits because they are relatively low in fat and high in protein, and contain functional amino acids and minerals.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.53 no.3
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• pp.382-387
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• 2020

This study compared the nutritional characteristics of seasoned laver Pyropia yezoensis with conger eel Conger myriaster seasoning sauce (SL-CES) with those of commercial seasoned laver (C-SL). SL-CES had higher protein and lower ash contents than those of C-SL. However, the moisture and lipid contents did not differ between them (P>0.05). The total amino acid content of SL-CES was 21.79 g/100 g, similar to that of C-SL (21.49 g/100 g). The major amino acids in SL-CES were aspartic acid, glutamic acid, and alanine. The SL-CES contained 125.7 mg calcium, 461.6 mg phosphorus, 2183.7 mg potassium, 9.5 mg iron, and 2.6 mg zinc per 100 g SL-CES. These amounts were all higher than those in C-SL, except for Zn. The major fatty acids in SL-CES were 16:0, 18:1n-9, and 18:2n-6.

• Korean Journal of Food Science and Technology
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• v.46 no.6
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• pp.778-781
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• 2014

Intense pulsed light (IPL) is a nonthermal technology emerging as an alternative to conventional thermal treatment. The purpose of this study was to investigate the effect of IPL treatment on the microbial inactivation, color alteration, and temperature change of dried laver to evaluate the commercial feasibility of IPL as a sterilization method. IPL treatment (10 min at 1,000 V and 5 pps) resulted in approximately 1.6 log CFU/g decrease in microbial cell viability. After IPL treatment, the surface temperature of dried laver increased by $1.9^{\circ}C$. The color lightness of dried laver increased with increased treatment time, while redness and yellowness decreased. However, these color differences were not significant.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.52 no.4
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• pp.311-320
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• 2019

This study aimed to optimize mixing conditions (adding amount of squid skin and sea tangle Saccharina japonica) for concentrates of octopus Octopus vulgaris cooking effluent (COCE) and roasting conditions (temperature and time) of seasoned Laver Pyropia yezoensis with concentrates of octopus cooking effluent (SL-COCE) using response surface methodology (RSM). The results of RSM program for COCE showed that the optimum independent variables ($X_1$, squid skin amount; $X_2$, sea tangle amount) based on the dependent variables ($Y_1$, odor intensity; $Y_2$, amino-N content; $Y_3$, sensory overall acceptance) for high-quality COCE were 0.53% (w/w) for $X_1$ and 0.48% (w/w) for $X_2$ for uncoded values. The results of the RSM program for SL-COCE showed that the optimum independent variables ($X_1$, roasted temp.; $X_2$, roasted time) based on the dependent variables ($Y_1$, burnt odor intensity; $Y_2$, water activity; $Y_3$, sensory overall acceptance) for high-quality SL-COCE were $344^{\circ}C$ for $X_1$ and 8 sec for $X_2$ for uncoded values. The SL-COCE prepared under optimum procedure was superior in sensory overall acceptance to commercial seasoned laver.