• Journal of Food Hygiene and Safety
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• v.16 no.3
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• pp.241-246
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• 2001

Distribution of pathogenic vibrios in the seawater of live fish tank and effect of environmental factors on their existence were investigated by collecting samples from fish markets and restaurants in 6 different cities. Pathogenic vibrios and coliforms were determined by using the most probable number (MPN) procedure, and aerobic plate count was enumerated by the standard pour plate method. No Vibrio chulerae O1 was detected in all the samples tested. Detection rates of V. cholerae non-O1, V. parahaemolyticus and V. vulnificus in all the smaples tested were 7.7%, 69.2% and 23.1%, respectively. Water temperature and trubidity of the seawater measured were higher in the pathogenic vibrios positive samples than in those negative samples. However, higher salinity and pH were shown in the pathogenic vibrios negative samples than in positive samples. The aerobic plate counts and MPN or total and focal coliforms in the seawater were higher in the presence of pathogenic vibrios than in the absence of pathogenic vibrios. In this study, the presence of pathogenic vibrios in the seawater tested was closely related with other physiochemical parameters and populations of coliforms, indicators far food safety.

• The Korean Journal of Food And Nutrition
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• v.26 no.3
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• pp.414-420
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• 2013

The aim of this study was to investigate the effects of environmental factors such as temperature, salinity, turbidity and pH on the growth of pathogenic Vibrios. In this study, we was obtained the samples from 2 different sites of the Incheon coastal area between January 2012 and December 2012. The water temperature in August and September was the high. the Incheon port changes the width of a small, wherease in the case of Hanjin harbor of changes of larger width. Salinity and turbidity showed significant differences, whereas temperature and hydrogen ion concentration was not significant. Pathogenic vibrios was determined using the real-time PCR method. Pathogenic vibrios in the Incheon port and Hanjin harbor were detected in 11 samples (91.67%) and 9 samples (75.0%) of Vibrio cholerae, 7 samples (58.3%) and 6 samples (50.0%) of V. vulnificus, 10 samples (83.3%) and 12 samples (100.0%) of V. parahaemolyticus, respectively. Pathogenic Vibrio bacteria were the highest at $26.8^{\circ}C$ of seawater in August. Quantitative results were the following: 102 $cell/m{\ell}$ in Vibrio cholerae, 7.876 $cell/m{\ell}$ in V. vulnificus, and 503.4 $cell/m{\ell}$ in V. parahaemolyticus, respectively. The enumeration of pathogenic vibrios showed a positive correlation with temperature and pH, but was negatively correlated with salinity and turbidity.

• Korean journal of food and cookery science
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• v.26 no.3
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• pp.300-306
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• 2010

Arabica coffee has been classified for trading according to the New York Board of Trade (NYBOT) green coffee classification. The aim of the present study is to evaluate the physiochemical and sensorial characteristics of coffees classified by NYBOT as NY2 (specialty coffee), NY3/4 and NY4/5 (commercial coffee). The density of green coffee was higher for the NY2 sample. The amount of total solids in brewed coffee increase as the green coffee grade decreased and the pH levels decreased as the coffee grade decreased. Descriptive analysis using a 15cm line scale was carried out by 12 trained panelists prepared by espresso coffee and consumer preference tests were carried out by 168 consumers. The NY2 sample had the highest fruity, acidity, sweetness and aftertaste characteristics. In addition, green, rio, sour and astringency characteristics increased as the coffee grade decreased. Acceptance of aroma, flavor, taste balance and overall were higher for the NY2 sample. In the consumer preference test, the NY2 and NY4/5 samples had a similar distribution, but consumers between the ages of 20 to 30 who like to drink brewed coffee more than instant coffee preferred the NY2 than sample over the NY3/4 sample. In conclusion, significant differences were observed among the three groups of green coffee classification in all physicochemical and sensory parameters.

• Bulletin of the Korean Chemical Society
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• v.25 no.10
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• pp.1525-1530
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• 2004

Mutagen X (MX) exists in our drinking water as the bi-products of chlorine disinfection. Being one of the most potent mutagen, it attracted much attention from many researchers. MX and its analogs are synthesized and modeled by quantitative structure activity relationship (QSAR) methods. As a result, factors affecting this class of compounds have been found to be steric and electrostatic effects. We tried to collect all the data available from the literature. With both CoMFA and CoMSIA various combinations of physiochemical parameters were systematically studied to produce reasonable 3-dimensional models. The best model for CoMFA gave $q^2$ = 0.90 and $r^2$ = 0.97, while for CoMSIA $q^2$ = 0.85 and $r^2$ = 0.94. So the models seem to be reasonable. Unlike previous result of CoMFA, in our case steric parameter alone gave the best statistics. Although the steric contribution was found to be the most important in both CoMFA and CoMSIA, steric parameter along with electrostatic parameter produced slightly better model in CoMSIA. Overall, steric contribution is clearly the most important single factor. However, when we compare chlorine and bromine substitution, chlorine substitution can be more mutagenic. This indicates that other factors such as electrostatic effect also influence the mutagenicity. From the contour maps, steric contribution seems to be focused on rather small area near C6 substituent of the furanone ring, rather than C3 substituent. Therefore the locality of steric contribution can play a significant role in mutagenicity.

• The Korean Journal of Malacology
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• v.29 no.1
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• pp.51-63
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• 2013

To assess the effect of environmental factors on the sustainability of cultured production shellfish, we investigated the habitat characteristics of tidal flat (Namhae-po in Taean). We measured the physiochemical parameters (temperature, salanity, pH, dissolved oxygen and nutrients) and the geochemical characteristics (chemical oxygen demand, ignition loss, C/N ratio and C/S ratio). Surface sediments were collected from several site of tidal flat to examine the geochemical characteristics of both the benthic environment and heavy metal pollution. The grain size for research area of tidal flat were similar at the ratio of silt and clay in comparison with the other site of it. The C/N ratio was more than 5.0, reflecting the range arising from the mix of marine organism and organic matter. The C/S ratio (about 2.8) showed that survey area had anoxic or sub-anoxic bottom conditions. The enrichment factor (Ef) and index of accumulation rate (Igeo) of the metals showed that those research areas can be classified as heavily polluted, heavily to moderately polluted, or more or less unpolluted, respectively. Adult surf clam (Mactra veneriformis) density was highest at St. 2 (middle part of the Namhae-po), on the other hand, surf clam spat density was highest at St. 3 (lower part of the Namhae-po). Heavy rain, terrigenous suspended clay with fresh water from neighboring agricultural land, and severe high air temperature during summer could be thought as detrimental causes of spat and adult mortality in Namhae-po tidal flat. We suggested that the growth of shellfish in the tidal flat was effected by the various environmental conditions, so an improvement in the cultured method was needed.

• Journal of Korean Society on Water Environment
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• v.32 no.3
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• pp.271-280
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• 2016

The aim of this study was to analyze spatial and temporal patterns of bacterial pollution levels and the relationship between bacterial pollutants and environmental parameters at the main stream and tributaries of Nakdong River. Water quality data including total coliform and fecal coliform were compiled from a total of 50 monitoring sites (30 at the main stream and 20 at the tributaries) along with rainfall and discharge data for three consecutive years from 2012 to 2014. During the study periods, the geometric mean values of total coliforms and fecal coliforms in the main stream were 74 (22~465) CFU/100 mL and 8 (3~42) CFU/100 mL, respectively. The geometric mean values of total coliforms and fecal coliforms in the tributaries were 275 (36~5,145) CFU/100 mL and 6 (1~1,352) CFU/100 mL, respectively. High concentrations of fecal coliforms were observed at Gumi (M 10), Hyeonpung (M 19), Hapcheon (M 23), and Namji (M 25) in the main stream, whereas Gamcheon (T 6), Bakcheon (T 7), Geumho-gang (T 8), and Gyeseongcheon (T 16) were identified as pollution hot spots in the tributaries. Although bacterial pollution levels showed complex behavior across monitoring sites and time, the highest coliform concentrations were routinely observed in the monsoon season between July and September of each year, indicating that the pollution levels were strongly dependent on precipitation in addition to other physiochemical parameters. Statistically significant correlations were found between fecal coliform concentrations and precipitation (r=0.403, p<0.01), followed by SS (r=0.425, p<0.01), nutrient TP (r=0.388, p<0.01), organic matter COD (r=0.322, p<0.01), and PO₄-P (r=0.317, p<0.01) in the main stream in the order of correlation coefficient from high to low.

• Asian-Australasian Journal of Animal Sciences
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• v.28 no.11
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• pp.1629-1640
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• 2015

This study was performed to compare carcass traits, sensory characteristics, physiochemical composition, and contents of nucleotides, collagen, and free amino acids among quality grades (QG) and to understand the association between QG and above parameters in loin and rump of Korean cattle steer. Loin and rump samples were obtained from 48 Korean cattle steers with each of four QG (QG 1++, 1+, 1, and 2; average 32 months of age). Carcass weight and marbling score (MS) were highest in QG 1++, whereas texture score measured by a meat grader was highest in QG 2. A correlation analysis revealed that MS (r = 0.98; p<0.01) and fat content (r = 0.73; p<0.01) had strong positive correlations with QG and that texture had a strong negative correlation (r = -0.78) with QG. Fat content in loin was highest but protein and moisture contents were lowest in QG 1++. Our results confirmed that a major determinant of QG is the MS; thus, intramuscular fat content. The International Commission on Illumination $L^*$, $a^*$, and $b^*$ values in loin were highest in QG 1++. Numeric values of shear force in loin were lowest in QG 1++, whereas those of tenderness, juiciness, and overall acceptability tended to be highest in QG 1++ without statistical significance. QG was strongly correlated with juiciness (r = 0.81; p<0.01) and overall acceptability (r = 0.87; p<0.001). All sensory characteristics were higher (p<0.05) in loin than those in rump. Adenosine-5'-monophosphate (AMP) and inosine-5'-monophosphate (IMP) contents in both loin and rump did not differ among QGs. No nucleotide (AMP, IMP, inosine, hypoxanthine) was correlated with any of the sensory traits. Total, soluble, and insoluble collagen contents in loin were higher in QG 1++ than those in QG 1. All three collagens had lower content in loin than that in rump. All three collagens were positively correlated with tenderness, juiciness, and overall acceptability. Glutamic acid content did not significantly differ among the four QGs in either loin or rump. In conclusion, it is confirmed that QG is associated with sensory traits but nucleotide contents in beef may not be a major factor determining meat palatability in the present study.

• Korean Journal of Food Science and Technology
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• v.32 no.4
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• pp.851-859
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• 2000

In the present study, changes in physicochemical and sensory properties, and microflora and enzyme activities, by addition of pumpkin (1, 2 and 5% pumpkin on the weight basis), of Sunchang sikhe kochujang, the most famous traditional kochujang, were investigated. Moisture content appeared to be reduced during fermentation, possibly due to exposure to the sun. Patterns of pH changes were rather complicated. pH of control kochujang was gradually reduced from the begining of fermentation up to 60 days of fermentation. Thereafter, it tended to be increased but again reduced after 90 days of fermentation. On the other hand, titratable acidity increased with fermentation reaching at the highest level at 90 day of fermentation and then slowly decreased. The addition of pumpkin induced a reduction in pH and an increase in titratable acidity, but this was due to organic acid contained in pumpkin itself. Contents of reducing sugar and amino nitrogen were increased by the addition of pumpkin in relation to the level of addition. Ethanol content was highly increased by the addition of pumpkin. Bacterial and yeast count, and activities of amylase and protease were not affected by the addition of pumpkin. Sensory evaluation test revealed that the addition of pumpkin improved sweet and savory taste, but color turned to be undesirable. However, none of tested parameters except color showed statistical significance.

• Asian-Australasian Journal of Animal Sciences
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• v.25 no.4
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• pp.515-523
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• 2012

The objective of this study was to investigate the variability in broiler performance, apparent metabolisable energy (AME) and ileal digestible energy (IDE) between five different maize samples fed with and without xylanase at 16,000 U/kg. Various in vitro characterisations were conducted to determine if any could predict performance or AME. Samples of the maize were harvested in five diverse regions and fed individually in a mash diet as follows (g/kg): test maize 608.3; soya bean meal (SBM) 324.1; poultry fat 25.2; salt 4.6; met 2.6; lys 1.6; thr 0.5; limestone 9.7, dical 18.4; vit/min 5.0; CP 210 and ME (kcal/kg) 3,085. The diets were fed to 720 broilers with 6 replicates, each containing 12 birds per treatment, from 0 to 18 d of age. Maize samples were analysed for starch, protein, crude fibre, fat, protein solubility index (PSI) and vitreousness using near infra red reflectance spectroscopy (NIR). They were also assayed using an in vitro starch digestibility method. The results showed that there was no effect of harvest region on the feed intake (FI), body weight gain (BWG) or feed conversion ratio (FCR) of the broilers over the 18 d period (p = 0.959, 0.926, 0.819 respectively). There was an improvement in all parameters with the addition of xylanase (FI p = 0.011; BWG and FCR p<0.001). There was a significant positive effect of xylanase on IDE, AME, IDE Intake (IDEI) and AME intake (AMEI) (p<0.0001 in all cases). Although there was no significant effect of maize source, there was a strong trend towards variability in IDE (p = 0.066) and AME (p = 0.058). There were no significant correlations (p<0.05) between any proximate or physiochemical values and any performance or AME values. This may suggest that none of those selected were suitable predictors for performance or AME. The broilers performed well according to the breed guidelines, with slightly increased FI, increased BWG and similar FCR prior to the addition of xylanase. When FCR and BWG were analysed with FI as a covariate, xylanase addition remained significant suggesting that the improvement in BWG and FCR was driven by an increase in digestibility and nutrient availability.

• Journal of Aquaculture
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• v.20 no.1
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• pp.31-40
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• 2007

To find out the effect of the spat planting time and environmental factors in the arkshell, Scapharca broughtonii (Schrenck), we investigated the growth, survival rate of arkshell and habitat characteristics in Gamak Bay, Yeoja Bay and Saryang Island. We planted artificial spats of arkshell in Gamak Bay and Yeoja Bay at November 2004, and also planted domestic and Chinese natural spats in Saryang Island at March 2005. We measured growth, survival rate of arkshell, physiochemical parameters of the water mass (water temperature, salinity, dissolved oxygen, nutrients and chlorophyll a) and characteristics of the sediment (oxygen penetration depth, oxygen microprofiles, ignition loss and chemical oxygen demand) by monthly. The cumulative survival ratio of arkshell in Gamak Bay was the highest at December, whereas the ratio of arkshell in Yeoja Bay was recorded as 0% at October. The monthly growth rates of arkshell length in Gamak Bay and Yeoja Bay were the highest in May and the growth rate of the Korean arkshell in Saryang Island was higher than Chinese ones significantly. The high mortality (> 65%) of the arkshell in Yeoja Bay during summer probably caused by high water temperature, inflow of low salinity water, and low dissolved oxygen concentration in sediment. The concentrations of nutrient and sediment COD were considered to play an important role in the monthly survival ratio of arkshell in Gamak Bay and Sarayng Island. We suggest that the growth and mortality of arkshell might be influenced to the planting time of spat and the habitat characteristics.