• Journal of the Korean Society of Food Science and Nutrition
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• v.21 no.3
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• pp.319-326
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• 1992

The Louisiana crawfish industry comprises the largest concentration of crustacean aquaculture in the United States. Processing plants throughout the culture region annually generate as much as 80 million pounds of peeling waste during recovery of the 15% (by weight) edible tail meat. A commercial oil extraction process for recovery of carotenoid astaxanthin from crawfish waste has been developed. Crawfish pigment in its various forms finds applications as a source of red intensifying agents for use in aquaculture and poultry industries. Crawfish shell, separated in the initial pigment extraction step, is an excellent source of chitin. Applicable physicochemical procedures for isolation of chitin from crawfish shell and its conversion to chitosan have been developed. Crawfish chitosan has been demonstrated to be both an effective coagulant and ligand-exchange column material , respectively, for recovery of valuable organic compounds from seafood processing wastewater.

• Journal of the Korea Organic Resources Recycling Association
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• v.9 no.3
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• pp.55-69
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• 2001

To study the possibility of agricultural utilization of seafood processing wastewater sludges, the changes of temperature and humus, the form of organic matter and nitrogen and the germination ratio of plant during the composting were investigated. The results were summarized as follows. Temperature was rapidly increased at early stage of composting, reached to $67{\sim}76^{\circ}C$ in highest temperature at 3~5 days, and then decreased gradually fallen to $40{\sim}50^{\circ}C$ at 19 days after composting, at the point was upset firstly. The third upset was conducted at 60days after composting, and then the temperature was little changed. The contents of total organic matters in the compost for composting were down 4.5~8.0%. Ether extractable materials, resins and hemicellulose contents of the organic matters for composting were decreased with 35~77%, 32~69% and 19~30%, respectively. And cellulose, lignins and unknown materials contents in the organic matters for composting were increased a little, but water soluble polysaccharides of organic matters were little changed. Total nitrogen, amino sugar and amino acid nitrogen contents in the compost for composting were decreased with 20~42%, 11~49% and 23~65%, respectively. The contents of humic acid in the compost for composting were little changed, but contents of fulvic acid in the compost for composting were decreased gradually. Germination ratio of radish, chinese cabbage and cucumber were over 90%, when the compost produced at 30 days after composting was tested on plant germination.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.15 no.12
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• pp.7443-7450
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• 2014

To resolve shortcomings of high-rate anaerobic processes, such as high upward flow velocity, this study sought to improve the structure of the high-rate anaerobic reactor and evaluate its performance. The improved reactor was manufactured by adjusting the diameter and dividing the reactor into three parts. The evaluation of the structurally improved reactor revealed that the reactor could stabilize a single circuit, and prevent the accumulation of solid matter and leakage of microbes, thereby stabilize the microbes. In the process of anaerobic digestion, an increase in pH and alkalinity within the reactor was presumably attributed to bicarbonate created in the process of organic matter decomposition and due to the re-dissolution of some biogas. To maintain a high rate of organic matter removal, the reactor should be operated with more than 9 hrs of HRT and an organic matter load of under $10.kgTCODcr/m^3{\cdot}d$. The methane gas generated in the anaerobic digestion process showed a high content of 65~83 % at the organic matter load of over $7.7kgTCODcr/m^3{\cdot}d$. per removal of CODcr. The methane quantity was generated at $0.10{\sim}0.23m^3CH_4/kgCOD_{rem}$, showing that it was smaller than the theoretical methane generation amount (0.35) in the STP state. In the latter part of high-rate anaerobic process, an advanced treatment process was required to remove nitrogen.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.36 no.2
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• pp.80-87
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• 2003

Recovery conditions and characteristics of a high molecular soluble protein from surimi processing wastewater in marine manufacture using calcium powder of cuttle bone treated with acetic acid (ATC) were examined. Judging from results of total-N, pH, COD, turbidity and yields, optimal treatment concentration of ATC for recovery of high molecular soluble proteins from wastewater was $1.0\%.$ The protein recovered from seafood waste (PRW) was macromolecule weight. The COD value in the wastewater treated with ATC was very high. The PRW had a $78.4\%$ in moisture, $1.0\%$ in crude lipid and $5.7\%$ in crude ash. The proximate composition, except the crude ash, of the PRW was similar to that of commercial surimi. The PRW showed white index and similar in the content and in the composition of total amino acid to those of commercial surimi. From the results of sensory evaluation on white index and texture, the heat-induced surimi gel prepared with $5\%$ subsititution of the PRW for bulking agent of commercial surimi was not significantly different compared to that prepared with the original commercial surimi.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.36 no.3
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• pp.204-209
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• 2003

Utilization of soluble protein recovered from surimi wastewater using calcium powder of cuttle bone were examined. The crude ash content of the heat-induced surimi gel was increased linearly by increasing substitution ratio of recovered protein-ATC toward commercial surimi. Moisture (approximately $76\%$) and lipid $(0.2\%)$ contents were not change, but their protein contents were decreased 15.7 to $14.3\%$ depend on increasing of substitution ratio. The white index of the heat-induced surimi gel by color meter was increased up to $10\%$ of substitution ratio. There were no difference between $0\%\;and\;5\%$ substituted surimi gel in the gel strength. The sensory score on white index and texture of the heat-induced surimi gel did not change in 0 to $10\%$ as a substitution ratio of recovered protein-ATC toward commercial surimi, while decreased in more $15\%.$ The optimal substitution ratio of recovered protein-ATC as a bulking agent was $10\%.$ The heat-induced surimi gel prepared with $10\%$ substitution of recovered protein-ATC was similar to the content and composition of total amino. acids, and superior to calcium content and the ratio of calcium and phosphorus toward those of commercial surimi.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.33 no.1
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• pp.79-85
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• 2000

Proximate composition of concentrated oyster cooker effluent (COCE) was $70{\%}$ moisture, $8.55{\%}$ total nitrogen, and $18.6{\%}$ ash. Optimum conditions for enzymatic hydrolysis of COCE ($200 ml$) weve $pH 7.0{\~}7.5\;and 50{\~}60{\circ}C$ for 8 h reaction time with 0.128 U of Aspergillus oryzae PE protease(AOP), Hydrolysis of COCE led to an increase in free amino acids to 1.41 fold, with taurine comprising about $17.62{\%}$ of the total free amino acid. Fifty volatile flavor components were identified in COCE and 63 in enzyme treated COCE (HCOCE). Volatile flayer compounds we increased significantly in HCOCE when compared with untreated COCE. Results of this study might help to alleviate the current wastewater disposal problem caused by oyster cooker effluent.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.52 no.1
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• pp.27-34
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• 2019

The seasonal and spatial variation of pathogenic Vibrio species, such as V. parahaemolyticus, V. vulnificus, V. alginolyticus, and V. cholerae were investigated in seawater and in bivalves off the Gyeongnam coast of Korea, which is an important area for shellfish production, during the period 2013-2016. V. parahaemolyticus, V. vulnificus, V. alginolyticus, and V. cholerae were detected in 12.1%, 5.2%, 15.4%, and 0.9% of seawater samples, respectively. V. parahaemolyticus, V. vulnificus, V. alginolyticus, and V. cholera were detected in 21.9%, 7.1%, 12.2%, and 0.0% of shellfish samples, respectively. The Vibrio spp. in seawater and bivalve samples were detected at high levels during the summer to early autumn; however, the levels were low during the winter. Therefore, their occurrence was seasonally dependent and correlated with high water temperature, which is also the biggest factor contributing to foodborne outbreaks associated with Vibrio. Relatively high detection rates of the strains were also found in the sea area that was continually exposed to inland wastewater. Our findings show that continuous monitoring is needed to reveal the patterns of occurrence of these pathogens from marine samples collected off the Korean coast, to reduce seafood-borne outbreaks caused by Vibrio.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.34 no.5
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• pp.473-477
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• 2001

Chitosan has been used as an effective adsorbant for the treatment of wastewater from seafood processing. We investigated the effects of deacetylation degree (DD) and molecular weight (MW) of chitosan on protein adsorption ability and also the optimum conditions of chitosan treatment for protein adsorption in 3 kinds of protein (albumin, hemoglobin and albumin-myoglobin mixture) solutions. The higher deacetylation degree and the lower molecular weight chitosan, the higher adsorption for water soluble proteins was accomplished. The optimum pHs for adsorption of albumin, hemoglobin and albumin-myoglobin mixture (4: 1, w/w) were 4.0, 7.0 and 4.0 respectively and the optimum time was $3\~4$ hrs for all proteins. Sodium chloride in the model system of protein solution was a preventing factor for protein adsorption ability of chitosan (DD=$80\%$, MW=350 kDa).