• Korean Journal of Environmental Biology
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• v.34 no.3
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• pp.216-221
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• 2016

Level and distribution of fourteen polycyclic aromatic hydrocarbons (PAHs) in the agricultural water samples collected in the waterways located in Gyeonggi and Gangwon, Korea were determined for monitoring and risk assessment. A simplified, fast but effective extraction and clean-up methods combined with gas chromatography tandem mass spectrometry (GC-MS/MS) was employed to measure the concentration of the target compounds. The extraction of the analytes of interest in water sample (10 mL) was performed with acetonitrile (10 mL) and the salt. To purify the target PAHs, the clean-up procedure was employed with 2 mL tubes of dispersive solid phase extraction. The optimized method was validated with recoveries, method detection limit (MDL), accuracy and precision. Good recoveries for each PAHs at 10 and $25{\mu}g\;L^{-1}$ were achieved (60 to 110%, with RSD <20%) with linearity (>0.99). MDL for all the analytes was achieved with $0.2{\mu}g\;L^{-1}$. GC-MS/MS results showed that concentration of phenanthrene in the water samples from Gyeonggi (20 sites) ranged from 0.82 to $2.56{\mu}g\;L^{-1}$ and from Gangwon (15 sites) ranged from 0.83 to $1.62{\mu}g\;L^{-1}$. Other PAHs were not found in the water samples but the continuous monitoring for these areas were required.

• Korean Journal of Food Science and Technology
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• v.12 no.3
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• pp.150-157
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• 1980

In an attempt to evaluate the quality of food by sensory testing, the difference testing for commercial milk was conducted by selected members of a sensory panel. The results were summarized as follows: 1. Sensory panel of 40 persons were selected by the general basis of selection of panel members, by sensitivity test for primary taste, and by discriminatory ability test and trained to have normal abilities on the sensory testing for the quality of milk. 2. As a result of sensitivity test for 4 primary tastes by panel members, the solution concentration of salt, sour, bitter and sweet for which average recognition threshold was located were 0.0128 M sodium chloride, 0.0008 M citric acid, 0.0016 M caffeine and 0.0256 M sucrose, respectively. 3. As results of difference test of single stimuli, paired comparison test, duo-trio test and triangle test, a significant difference was recognized at higher level than the 1% among the samples of commercial milk produced by 5 companies.

• Journal of Animal Science and Technology
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• v.50 no.4
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• pp.509-518
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• 2008

This experiment was conducted to investigate enzyme activity, antimicrobial activity, and antibiotics susceptibility of Lactobacilli strain(Lactobacillus reuteri BLA5, Lactobacillus crispatus BLA7, Lactobacillus reuteri BLA9, Lactobacillus amylovorus LLA7, Lactobacillus crispatus LLA9, Lactobacillus vaginalis LLA11) isolated from chicken ceca and were selected by organic acid synthesis, acid tolerance, bile salt tolerance. The enzymes activities were different among strains of Lactobacilli. The amylase activity and lipase activity of Lactobacillus were high but cellulase activity and protease activity of that were low. Lactobacillus culture showed high antimicrobial activity against E. coli but low antimicrobial activity against Salmonella. The inhibitory factor of Lactobacilli isolated from chickens’ cecum on E. coli was low pH by organic acid. All of Lactobacillus isolated from chicken’s cecum were susceptible to ampicillin and amoxicillin but weren’t susceptible at the optimum level of feed additive antibiotics(virginiamycin and salinomycin).

• Korean Journal of Food Science and Technology
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• v.47 no.4
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• pp.419-424
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• 2015

The objective of this study was to investigate the physicochemical and antioxidant properties of a variety of commonly consumed commercial green tea. Green tea samples with the same commercial name produced at different regions were analyzed. High-grade tea samples showed higher values of lightness (L) and greenness (-a). Additionally, compared to other varieties of teas, high-grade tea samples showed higher levels of catechin, gallocatechin gallate (GCg), epicatechin gallate (ECg), theanine, and methylxanthines and a lower level of epigallocatechin (EGC). The antioxidant activity of green tea was also investigated using 1,1-diphenyl-2-picrylhydrazyl (DPPH) and 2,2'-azinobis (3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt (ABTS) radical assays. High-grade teas were observed to have higher antioxidant activities. The results of this study indicate that the catechin content, such as EGCg, GCg, and ECg levels, was found to positively influence the total antioxidant activity of green tea.

• Journal of the Korean Society of Food Culture
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• v.4 no.2
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• pp.161-166
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• 1989

This study was intended to observe the changes of the nitrate, nitrite and vitamin C content during the fermentation of Kimchies by some added materials. Eight different types of Kimchi, were prepared with chinese cabbage and seasonings, to which added respectively materials such as soused anchovy, soused shrimp, garlic, mustard leaf, K-sorbate, ascorbic acid, radish. After they were prefermented at $18^{\circ}C$ for 24 hours, stored 35 days at $4^{\circ}C$. Generally optimal maturity of Kimchi showed pH 4.4 to 4.6, lactic acid content 0.3 to 0.4% at salt content belows 2.5%. The content of total vitamin C in Kimchies was approximately 19.8-24.7 mg/100g at the initial stage of fermentation and then slightly decreased. When the process of the fermentation was active, the content of total vitamin C increased up to the same level or higher than that of the initial stage and then gradually decreased. In the case of Kimchi which added garlic, the content of vitamin C was relatively higher then the other samples. In the initial stage of fermentation, the nitrate and nitrite content in the Kimchi which added garlic and raddish were relatively higher than other samples. Nitrate content reached its minimum by the 21st day, at that time content was 290-342 ppm. At this time, the nitrite was not detected and total vitamin C content in all samples decreased.

• The Korean Journal of Food And Nutrition
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• v.10 no.1
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• pp.60-64
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• 1997

This study attempted to examine the effect on sensory characteristics and texture of Paeksolgi in various volume of adding sugar and steaming time. The most favorite tendency on the quality was over 15% adding sugar and 20 minute steaming time. Evaluation was conducted through objective evaluation firstly and sensory evaluation secondly. The volume of adding sugar was the significant factors which affected the textual characteristics of Paeksolgi. But steaming time and interaction had not affected. In sensory evaluation on the various steaming time Paeksolgi made by steaming time for 20min and over 15% adding sugar showed the most favorite tendency on the overall quality. This condition corresponded to the high level of hardness, adhesiveness, gumminess in comparison with Rheoner measurement. In summary the most favorite factor was 12 hours of soaking time, 10% adding water, 1% of adding salt, over 15% adding sugar, 20 minutes steaming time.

• Korean Journal of Food Science and Technology
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• v.22 no.7
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• pp.724-731
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• 1990

The fermentation process of Andong Sickhae including optimal composition of the product was investigated. Through sensory evaluation and ingredient analysis of ten samples prepared in the laboratory and the samples collected from Andong region, we found that the ratio of ingredient of the product by weigh are as follow : [glutinous rice(80) : malt(50) : radish(100) : water(500) : ginger(8) : red pepper(4)]. The level of nitrogen compound turned out to be low while that of soluble protein and salt soluble protein was high. The content of total sugar and reducing sugar was found to be considerable high and among the free sugar, maltose was the highest(80%), followed by glucose and maltotriose. Activities of acid protease and saccharogenic amylase were 1.55 unit per milliliter and $12.5D^{40}_{30}^{\circ}$ respectively. Results of sensory evaluation showed that the good Andong Sickhae turned out to have well harmonized taste of flavor, sweetness and sourness while the color looked slightly red.

• Journal of the Korean Home Economics Association
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• v.43 no.12 s.214
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• pp.61-78
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• 2005

This study was peformed to assess the relationships among bone mineral density(BMD), nutrient intake and lifestyle factors in postmenopausal women. A trained nutritionist examined the interviewed usual dietary intake and physical activity of 85 subjects in Chungnam with a questionnaire interview, and BMDs of the lumbar spines($L_2-L_4$), femoral necks(FN), ward's triangles(WT) and trochanters(TR) were measured by dual energy X-ray absorptiometry (DEXA). The BMDs(T-score) of $L_2-L_4$, FN, and WT were $0.996g/cm^2(-1.601),\;0.697g/cm^2(-1.697)$, and $0.793g/cm^2(-1.512)$, respectively, which were assessed as osteopenia by T-score,. and TR was normal at $0.718g/cm^2(-0.675)$. Subjects included 85 in Chungnam were divided into three groups according to the BMD measurement of the $L_2-L_4$ and FN assessed by T-score. The percentages of the osteoporosis, osteopenia, and normal groups were $32.9\%,\;42.4\%$ and $24.7\%$ respectively. The average age was significantly the highest of the osteoporosis group than in the other two osteopenia or normal groups(P<0.001). Among lifestyle factors, the BMD of lifestyles was significantly related with exercise but it was not significant with medication., salt. intake, bone fracture, coffee consumption, drinking and smoking. The nutrient intake of the subjects was most nutrient intake adequate to the Korean RDA level for most nutrients excepting energy intakes and calcium. The BMD of lumbar spines $L_2-L_4$ showed significant positive association with the intake of most nutrients except carbohydrate, especially in the normal group. The Higher BMD levels were found for those with high intake of protein and vitamin B1. The BMDs of $L_2-L_4$, and FN were positively correlated with showed energy expenditure, exercise, miscellaneous activity, per weekend and week(P<0.05) in normal group but that was showed negatively correlated in the osteopenia group. Therefore, this study confirmed that one of the most effective ways to minimize bone less in postmenopausal women is to maintain an adequate intake of calcium and other nutrients and regular physical activity.

• Food Science and Preservation
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• v.20 no.5
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• pp.699-704
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• 2013

Buckwheat Soksungjang (BS) is a bealmijang manufactured with buckwheat and soybeans. We manufactured BS using Bacillus subtilis HJ18-4 (HJ18-4), which has high enzyme activities and antibacterial effects. HJ18-4 was inoculated in a different process during the BS manufacturing, which was the meju-making time (Treat 1), and the salt water time was added (Treat 2). The physiochemical and microbial characteristics of the BS were analyzed. As a result, the total aerobic counts (7~8 log CFU/mL) in the BS increased after 15 days of fermentation. Especially, Treat 1 showed higher total aerobic counts and amino-type nitrogen (65.38~202.52 mg%) than Treat 2. During the BS fermentation, the reduction of the sugar contents and the enzyme (protease and amylase) activities decreased. In the relative quantitative expression level of PlcR, Treat 1 did not show toxin gene expressions at the end of the fermentation on Day 23. Treat 1 showed suitable B. cereus physiochemical quality characteristics and inhibition effects. When the modified-form type of fermented soybean paste was manufactured with a single starter, it could not reproduce the natural fermentation quality. These results suggest that the addition of a starter (HJ18-4) in the Meju manufacturing process could enhance the quality characteristics of the manufactured BS via natural fermentation and by suppressing B. cereus.

• Clean Technology
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• v.5 no.1
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• pp.78-85
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• 1999

In the Kimchi manufacturing industry that has recently been on its greatest growth, the rinsing process for salt-pickled Chinese cabbage in a brining step generates a vast amount of rinsing wastewater containing salts, colloids, and organics released from the raw material. In this study, the experimental method was developed to optimize the rinsing water consumption and thus to minimize the rinsing wastewater generation. The continuous counter-current rinsing basin in the actual plant was simulated through the lab-scale three batch-wise rinsing tanks. Rinsing efficiencies for the brined cabbage from the same brining tank were almost in the same level, whereas those varied substantially from source to source in the raw Chinese cabbage provided. When rinsing water used were decreased from 3.3 L/head to 2.7 L/head, no significant change was observed with respect to COD, turbidity, conductivity, $Na^+$, and $Cl^-$ concentrations in the extracted solution of the rinsed cabbage. However, the quality of the extracted solution was badly deteriorated as the amount of rinsing water used dropped down to below 2.7 L/head. The reduction of rinsing water up to 18% was proved to be possible without any negative effect on the quality of the product, Kimchi.