• Korean Journal of Food Science and Technology
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• v.19 no.2
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• pp.157-163
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• 1987

Changes in the odor components of Sergia Lucens during fermentation were studied by simultaneous distillation and extraction method. Forty seven components were identified by GC and GC-MS. Major cooked odor components of raw material were alkyl pyrazines and thialdine. Alkyl pyrazines, furfuryl alcohol, isoamyl alcohol and sulfide compounds, such as dimethylsulfide and dimethyltrisulfide increased during the period of fermentation. On the other hand, thialdine content decreased as the period of fermentation was extended. Sensory evaluation of cooked Sergia Lucens odor was carried out by GC-sniff analysis. The odors of GC effluents at the sniffing port were sniffed in order to find out the key compound of cooked Sergia Lucens odor components. The results of the GC-sniff analysis indicated that 2,5-dimethylpyrazine, 2,6-dimethylpyrazine and 2,3-dimethylpyrazine had dried or roast shrimp-like odor and thialdin had dried small sardine-like odor. The result showed that pyrazines and thialdine could play an important role in the formation of cooked Sergia Lucens odor.

• Journal of Food Hygiene and Safety
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• v.33 no.2
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• pp.118-123
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• 2018

The objective of this study was to develop a sensitive method for the identification and determination of nitrovin in fishery products by using a solid-phase extraction (SPE), as performed with a liquid chromatography-tandem mass spectrometry (LC-MS/MS). The samples were extracted with a mixture of acetonitrile and water, and were then defatted with acetonitrile saturated hexane, after which further clean-up was accomplished with SPE on the hydrophilic-lipophilic balance (HLB) cartridges. The analytes were subsequently ionized in the positive mode of an electrospray ionization (ESI), and where thereby detected in a process of multiple reaction monitoring (MRM). The linearity (expressed as correlation coefficients) of the matrix calibration curves was > 0.985. The limit of the quantification for the nitrovin was measured at 0.001 mg/kg. The accuracy (expressed as average recovery) was noted between 72.1 and 122%. The precision (expressed as coefficient variation) was noted from 2.9 to 16.9%. According to the CODEX CAC/GL-71 guideline accuracy, precision, linearity, and limit of detection were determined in three matrices (which were flatfish, eel and shrimp). The proposed method was suitable for analyzing the associated nitrovin residues. This application and result can also be a factor to contribute to the non-detection drugs management in fishery products.

• Journal of the Korean earth science society
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• v.43 no.5
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• pp.618-638
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• 2022

The Middle Jurassic granite dike swarm intruding into the Paleoproterozoic banded gneiss is pervasively observed in Ueumdo, Hwaseong City, mid-western Gyeonggi Massif. Based on their cross-cutting relationships in a representative outcrop, there are four dikes (UE-A, UE-C, UE-D, UE-E), and depending on the direction, there are three granite dike groups, which are NW- (UE-A dike), NW to WNW- (UE-C dike), and NE-trending (UE-D and UE-E dikes). These granite dikes are massive, medium-to coarse-grained biotite granites, and their relative ages observed in outcrops are in the order of UE-A, UE-D (=UE-E), and UE-C. The geometric analysis of the dikes indicates that the UE-A and UE-C dikes intrude under approximately NE-SW trending horizontal minimum stress fields. The UE-A dike, which showed a relatively low average SiO2 content by major element analysis, is a product of early magma differentiation compared to other dikes; therefore, it is consistent with the relative age of each dike. The ²⁰⁶Pb/²³⁸U weighted mean ages for each dike obtained from SHRIMP zircon U-Pb dating were calculated to be 167 Ma (UE-A), 164 Ma (UE-C), 167 Ma (UE-D), and 167 Ma (UE-E), respectively. The samples of the UE-A, UE-D, and UE-E dikes showed very similar ages. The UE-C dike shows the youngest age, which is consistent with the results of the relative age in the outcrops and major element analysis. Therefore, the granite dikes intruded into the Middle Jurassic (approximately 167 and 164 Ma), coinciding with those of the Gyeonggi Massif, where the Middle Jurassic plutons are geographically widely distributed. This result indicates that the wide occurrence of the Middle Jurassic plutons on the Gyeonggi Massif was formed as a result of igneous activity moving in the northwest direction with the shallower subduction angle of the subducting oceanic plate during the Jurassic.

• Journal of Food Hygiene and Safety
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• v.35 no.5
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• pp.447-451
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• 2020

For this study, we conducted a simultaneous multiresidue analysis of veterinary drugs in cultured fishery products in Chungnam Province in 2018. A total of 115 fishery product samples were obtained from fish farms and fishery production sites located in the province. In all, 29 residual veterinary drugs in the samples were analyzed using a validated liquid chromatography-tandem mass spectrometry (LC-MS/MS) method. As a result, veterinary drug residues were only detected in a small number of the 106 samples (92.2%), and the detection rate was 7.8% (9 of 115 samples). The amounts were also below maximum residual limit (MRL) for fishery products, although one sample exceeded the MRL allowed by the Ministry of Food and Drug Safety and was detected in loach. The nine residual veterinary drugs were detected in 8 samples: loach, eel, catfish, freshwater bream, flatfish, rockfish and shrimp. The detected veterinary drugs were oxolinic acid, enrofloxacin, ciprofloxacin, sulfadiazine, flumequine and oxytetracycline. The most frequently detected antibiotic was oxolinic acid, and enrofloxacin exceeded the MRL in loach sample. Residues of most veterinary drugs were either not detected or were below the MRL, and while the status of fishery products is seen as safe overall, current surveillance efforts over veterinary drugs should be continued.

• Journal of Aquaculture
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• v.21 no.4
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• pp.309-316
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• 2008

Effects of the various dietary additives on growth and tolerance of abalone Haliotis discus hannai to the stresses were determined in the 16-week feeding trial. Seventy juvenile (an initial body weight of 4.2 g) abalone per container were randomly distributed into 21, 50 L plastic rectangular containers each. The six kinds of experimental diets were prepared: control (CON) with no additive, by-product of green tea (BPG), extract of figs (EF), extract of green tea (EG), commercially available product of Hearok (PH), and Haematococcus (HC). In addition, dry sea tangle (ST) was prepared to compare the efficiency of the experimental diets. Fishmeal, soybean meal and shrimp head meal were used as the protein source, and dextrin, sea tangle powder and wheat flour, and soybean oil and fish oil were used as the carbohydrate and lipid sources, respectively in the experimental diets. The experimental diets were fed to abalone once a day at a satiation level with a little leftover. The feeding trial lasted for 16 weeks. At the end of the 16-week feeding trial, abalone was exposed to the different types of stresses (air exposure, and sudden changes of rearing temperature and salinity). Survival of abalone fed the sea tangle was highest. However, weight gain of abalone fed the EF, EG and PH diets was significantly (P<0.05) higher than that of abalone fed the BPG diet or dry sea tangle. Shell length of abalone fed the all experimental diets was significantly (P<0.05) higher than that of abalone fed the dry sea tangle. Accumulated mortality of abalone fed the sea tangle was low when exposed to the different types of stresses. Also, relatively low mortality was achieved in abalone fed the HC and EF diets. In considering these results, it can be concluded that the various sources of additives is effective to improve production of abalone, and Haematococcus and extract of figs can be considered as dietary additives to improve resistance of abalone against the different types of stresses.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.22 no.2
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• pp.49-58
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• 1989

For the effective utilization of anchovy as a food source, this work was undertaken the com-parison in food quality of anchovy snacks and its changes during storage at room temperature ($24\pm4^{\circ}C$). Chopped anchovy was mixed with soft flour($340.0\%$, w/w), corn starch($10.0\%$, w/w), sodium chloride($2.5\%$, w/w), monosodium glutamate($0.1\%$, w/w), sodium bicarbonate ($2.5\%$, w/w), water($5.6\%$, w/w), onion powder($0.3\%$, w/w), garlic powder($0.3\%$, w/w), red pepper powder($0.3\%$, w/w) and sodium erythorbate($0.2\%$, w/w), The mixture were rolled, aged, co沇ed, dried and finally parched or deep-fried at $190\pm10^{\circ}C$. The anchovy snacks were packed in the casted polypropylene film bag ($16cm{\times}14cm$), The changes in moisture contents, water activity, pH, volatile basic nitrogen, contents of amino acid and color values of products were negligible during storage. The results of TBA value and peroxide value showed that lipid oxidation can be retarded by adding antioxidant and spices. Judging from contents of amino acid and mineral, the products were more nutritive than the sold shrimp snack on the market. From the results of sensory evaluation and chemical experiments, the product prepared with sodium erythorbate could be preserved in good quality during storage of 120 days.

• Journal of Food Hygiene and Safety
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• v.28 no.2
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• pp.124-129
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• 2013

The method for detection foods containing allergenic materials by PCR was developed in this study. To detect allergenic raw material from processed food, species specific primer which up to 200bp for PCR product were designed or selected from advanced research. As target materials, 14 items were selected (12 target materials for allergen in Korea, 2 target materials for allergen in foreign countries). The amplicon size for eggs, milk, buckwheat, peanuts, beans, wheat, mackerel, crab, shrimp, pork, peach, tomato, almond, and sesame were confirmed 281, 131, 138, 120, 118, 127, 211, 174, 231, 138, 174, 132, 103, and 220bp, respectively. And any non-specific bands were not detected among each others. Detection method for allergenic material developed in this study could be used to investigate inaccurate goods for allergen labeling or non-intentional contaminant during processed foods manufacturing. In addition, the system will be usefully to detection accurate allergenic raw materials of export for other countries.