• Journal of Food Hygiene and Safety
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• v.37 no.4
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• pp.207-215
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• 2022

The intensity of fishy odor in eggs, which differs depending on the poultry type and individual perception, can be due to many factors including trimethylamine (TMA) which has been identified as the main. Notably, riboflavin can increase the activity of flavin-containing monooxygenase 3, the enzyme responsible for converting TMA into odorless trimethylamine-N-oxide. This study aimed to analyze the TMA content in egg yolk, evaluate its contribution to fishy odor, and develop a method to prevent this undesired odor. Solid-phase microextraction-gas chromatography/mass spectrometry was used to detect and quantify volatile compounds in egg yolk from hens fed a standard TMA-rich diet and hens fed a riboflavin-supplemented diet. To compare the relative content of volatile substances between eggs, a correlation study was performed using an electronic nose. Higher concentration of TMA (1.06 ± 0.12 mg/kg) was detected in egg yolks obtained from hens fed a normal diet than those fed a riboflavin-supplemented diet. Overall, this study suggests that riboflavin affects the quantity and quality of volatile substances, including TMA, present in eggs and we expect these findings to improve the quality and reduce the fishy odor of eggs.

• Journal of the Korean Society of Food Culture
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• v.37 no.2
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• pp.133-142
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• 2022

The purpose of this research was to examine the preferences of five traditional Korean drinks and analyze the factors affecting the preferences of children aged 7-12 in Korea, Vietnam, and China. The samples used in a sensory test were omija-cha, yuza-cha, sujeonggwa, sikhye and misutgaru. The test was performed to examine the overall, appearance (color), odor, taste and mouth-feeling and a sweetness intensity using 5 point hedonic scale (1=dislike extremely, 5=like extremely) and, check-all-that-apply (CATA) method was performed to determine preference and non-preferences factors. The preference of all samples except sujeonggwa showed significant differences in all items of the preferences (p<0.001). Almost items of the preference was rated more than 4 points in Chinese and Korea children. The sweetness intensity showed also significant differences in all items of the preferences except sujeonggwa (p<0.001), and evaluated as not sweet-appropriate with the score between 2 and 3 points. Sweetness, color, mouth-feeling, familiar flavor and healthy feeling was selected for the factors affecting the preferences. In conclusion, the result of this study determine the preferences and the affecting factors for the traditional Korean drinks in children of Korea, Vietnam, and China.

• Korean journal of food and cookery science
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• v.29 no.5
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• pp.489-500
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• 2013

This study was conducted to establish an effective palate cleanser when conducting descriptive analysis for gochujang products. In addition, descriptive analysis procedure for gochujang products was optimized. A generic descriptive analysis was performed on 4 types of gochujang samples varying in hot and spicy levels. The sensory attributes developed were 9 odors, 13 flavors, 4 texture and mouth feel attributes, and 4 appearance attributes. In order to select an effective palate cleanser for gochujang, 5 types of cleansers were tested (water, water+bread, water+cucumber, water+milk, water+cracker). Correct answering rate, significant numbers of product effect on sensory attributes, and the mean hot and spicy intensity values were considered to select the optimal palate cleanser. Results showed that as the hot & spicy level increased, red pepper odor and flavor significantly increased whereas umami taste intensity decreased. When comparing the efficiencies of various palate cleanser, the correct answer rates were the highest when warm water was used with either cucumber or cracker. Additionally, the attribute intensities were better differentiated between gochujang samples when cracker, white wheat bread, or cucumber were used. Overall, warm water with cucumber or cracker were shown to be the most effective cleansers.

• Korean Journal of Soil Science and Fertilizer
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• v.40 no.4
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• pp.242-248
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• 2007

To find a feasibility of utilization of food waste slurry (FWS) generated during composting, FWS was combined with pig manure slurry (PMS) in various ratios and the change of nutrient contents and offensive odor of the combined slurries before and after fermentation were studied. The initial pH was 7.67 for PMS and 8.45 for FWS. However, during the fermentation, pH increased in the combined slurries with the higher FWS rate among the treatments while decreased in thosewith higher PMS rate. EC of each slurry sample showed that the difference among combined slurry samples has been reduced during fermentation and became stabilized in $21{\sim}23dS\;m^{-1}$ after 180 days. After 180 days fermentation, total nitrogen (T-N) decreased. T-N of mixture with a half and more FWS decreased up to 0.1%, less than the critical level (0.3%). The contents of O.M., T-N, phosphorus, calcium and magnesium decreased with fermentation while those of potash and salinity increased. From initial fermentation until 30 days, a lot of $NH_3$, as an offensive odor, was produced. However, it decreased steadily, except in higher PMS rate. In terms of producing $50{\mu}g\;ml^{-1}$ of $NH_3$, the top layer took 30 days after fertilization with FWS only, 45 days for utilized treatment with F75 (25 % of PMS), 75 days for utilized with F50 (50%) and F25 (75%) and 90 days for PMS only, respectively. $RNH_2$ also had similar trend with $NH_3$ but it was produced continuously as long fermentation proceeded. In terms of $RNH_2$, the decrease in concentration up to $50{\mu}g\;ml^{-1}$ were; 45 days for FWS only(F100), 105 days for F75 utilization, 120 daysfor F50, 165 days for F25, respectively. ethyl mercaptan was produced in PMS until 180 days after fertilization but it was not produced in FWS. Sensory tests as an integrated test of offensive odor were also done. FWS showed lower than 1 after 30 days from initial fermentation, while PMS had still offensive odor even up to 180 days from initial fermentation. It is probably affected by the continuous production of ethyl mercaptan and amines. However, considering in decrease T-N content caused by volatilization while offensive odor intensity according to official standard of fertilizer is lower than 2. Further study on controlling offensive odor needs to be done.

• Proceedings of the KIEE Conference
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• 2001.07c
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• pp.1475-1477
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• 2001

In odor to set high saturation magnetization and coercivity, it had need to orient axis of easy magnetization of CoCr-based thin film perpendicular direction(c-axis) to the substrate plane. It was known that crystalline orientation of CoCr-based thin film was improved by introducing underlayer like Ti, Ge. We prepared singlelayer and double layer with Si underlayer by Facing Targets Sputtering System. As a result, intensity and c-axis dispersion angle ${\Delta}{\theta}_{50}$ of singlelayer were improved with increasing film thickness. Also, it was found that CoCr/Si and CoCrTa/Si double layer showed good c-axis dispersion angle due to introducing Si.

• Proceedings of the Korea Air Pollution Research Association Conference
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• 2002.04a
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• pp.203-204
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• 2002

시화, 반원공단은 수도권의 공장 분산정책에 의해 형성된 다양한 업종의 영세한 중소기업에 의해 구성된 공단이다. 서해안과 인접한 지역에 위치하며, 풍하방향에 배후 주거단지가 입주하면서 악취민원이 지속되고 있는 지역이다. 이러한 악취현상에 대응하기 위해 관련부처와 연구기관에서는 다양한 방법으로 악취현상의 규명노력과 저감대책을 시행하여 왔다 지금까지의 대부분의 악취 측정에 관한 연구는 주요 악취 발생지점에서의 악취원인물질을 규명하려는 노력에 집중되었고, 이 지역 악취현상의 공간적인 분포를 파악하기 위한 자료는 부족하였다. (중략)

• Korean Journal of Fisheries and Aquatic Sciences
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• v.42 no.6
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• pp.537-544
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• 2009

This study was conducted to improve yield and functional properties of autoclave-treated salmon frame extracts (SFETA) using commercial enzymes (Alcalase 2.4 L FG, Flavourzyme 500 MG, Neutrase 0.8 L and Protamex 1.5 MG). Yield and angiotensin I converting enzyme (ACE) inhibitory activity of all enzymatic hydrolysates improved compared to those of control (undigested extracts), which were the highest in hydrolysates incubated with Protamex 1.5 MG for 4 hrs (P4-treated hydrolysates) and 2 hrs (P2-treated hydrolysates), respectively. However, antioxidant activities of all enzymatic hydrolysates showed less than 29%. According to the trichloroacetic acid soluble-N, volatile component intensity and sensory evaluation, when compared to control, taste of P4-treated hydrolysates improved, while its fish odor strongly smelt. Therefore, for efficient use of P4-hydrolysates, the fish odor should be improved by Maillard reaction of extracts or pre-treatment of salmon frame.

• Journal of Korean Society on Water Environment
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• v.22 no.3
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• pp.521-526
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• 2006

We have studied the possibility of removing Anabaena macrospora by injecting copper sulfate ($CuSO_4{\cdot}5H_2O$) into the raw water of a drinking water purification plant. Anabaena macrospora caused the unpleasant geosmin odor of drinking water in August 2001. The cell break-point of A. macrospora was 0.3 mg/L of $CuSO_4$. We were able to reduce the standing crops of A. macrospora effectively because $CuSO_4$ could break A. macrospora selectively. Because 0.3 mg/L of $CuSO_4$ could break both cells and akinetes, it reduced the possibility of a recurrent problem for them to meet a favorable condition. When $CuSO_4$ was injected in the early growth phase of algae and the mixing intensity was high, A. macrospora could be removed most effectively. The odor caused by A. macrospora was sustained for a while without any sudden change of environmental condition. Therefore, we hope that it could shorten the period of obstacle by injecting the optimal amount of 0.3 mg/L of $CuSO_4$. The water quality, alkalinity, conductivity, hardness and pH didn't changed by the injection of $CuSO_4$.

• Journal of Korean Society for Atmospheric Environment
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• v.30 no.5
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• pp.492-503
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• 2014

In this study, emission characteristics of volatile odorant species released from urine samples were investigated in relation to two key variables: [1] storage conditions before sampling and [2] incubation conditions during sampling. To this end, 20 offensive odorants were quantified by four different analytical systems and then sorted according to seven functional groups. It is indicated that benzene (B), styrene (S), isobutyl alcohol (i-BuAl), butyl acetate (BuAc), butyraldehyde (BA), isovaleraldehyde (IA), and valeraldehyde (VA) did not contribute to urine odor because their concentration levels were measured below detection limits in all samples. On the other hand, emission concentrations of toluene (T), methyl ethyl ketone (MEK), methyl mercaptan ($CH_3SH$), carbon disulfide ($CS_2$), and ammonia ($NH_3$) were generally higher than other compounds. In terms of odor intensity (OI), $CH_3SH$ and $NH_3$ showed the largest OI values in the range of 2~4. According to t-test (storage approach and urine temperature), the results of T, $CS_2$, and $NH_3$ were statistically distinguished from each other in terms of differences in sampling temperature. Likewise, the emissions of certain odorants from urine samples were affected by changes in sample treatment conditions to a degree.

• Animal Bioscience
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• v.35 no.12
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• pp.1977-1985
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• 2022

Objective: This study was conducted to determine the seasonal characteristics of odorous material emissions from a swine finishing barn equipped with a continuous pit recirculation system (CPRS) using aerobically treated manure. Methods: The CPRS consists of an aerobic manure treatment process and a pit recirculation system, where the solid fraction is separated and composted. The aerated liquid fraction (290.0%±21.0% per day of total stored pig slurry) is continuously recirculated to the top of the slurry in the pit. Four confinement pig barns in three piggery farms were used: two were equipped with CPRS, and the other two operated a slurry pit under the slatted floor across all seasons. Results: The indoor, exhaust, and outside odor intensities were significantly lower in the CPRS group than in the control group (p<0.001). In the CPRS group, the odor intensity outside was significantly lower in the fall than in the other seasons (p = 0.015). In the indoor atmosphere, the temperature and CO₂, NH₃, and H₂S contents of the CPRS group were significantly lower than those of the control group (p<0.05). In the CPRS group, indoor temperature did not significantly change in the spring, summer, and fall seasons and was significantly lower in the winter (p = 0.002). NH₃, H₂S, methyl mercaptan, dimethyl disulfide, trimethylamine, phenol, indole, and skatole levels were significantly lower in the CPRS group than in the control group (p<0.05). There were significant seasonal differences on the odorous material in both the control and CPRS groups (p<0.05), but the pattern was not clear across seasons. Conclusion: The CPRS can reduce the indoor temperature in the summer to a level similar to that in the spring and fall seasons. The CPRS with aerated liquid manure is expected to reduce and maintain malodorous emissions within acceptable limits in swine facilities.