• 한국식생활문화학회지
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• 제12권3호
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• pp.265-274
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• 1997

This study was conducted in ordor to find the most suitable conditions for producing the Doenjang with optimal odor compound contents. Three sample groups with the different preparing methods -Doenjang that has not gone through the soy sauce separation process (Doenjang A), Doenjang that has gone through the soy sauce separation process; Meju-20% salt water ratio of 1 : 4 (Doenjang B), and that with the ratio of 1.3 : 4 (Doenjang C)- were tested during different ripening periods. Odor compound contents were analyzed through Solvent Extraction Method and Simultaneous Steam Distillation Extraction (SDE). The number of odor compounds was greatest in Doenjang A and during the mid to late stage in each groups. In the sensory evaluation of Doenjang odors, Doenjang A received the highest scores in the categories of overall preferences, while Doenjang C got the lowest scores. Individual odor didn't vary significantly during ripening periods, but the overall odor and taste preference was highest in the samples ripened for 75 to 120 days. Stepwise multiple regression analysis of major odor compounds of Doenjang revealed that benzeneacetaldehyde is the major explanatory variable for offensive odor. Benzeneethanol, 3-methylthio-propanal and 4-methyl-phenol are the explanatory variables for salty odor, nutty odor and rancid odor, respectively. Odor compounds that contribute to the overall odor preference varied from the compounds that affect the taste preference.

• 한국환경과학회지
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• 제11권4호
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• pp.399-403
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• 2002

This study was designed to analyse the odor from Nam river. The characteristic odor in the water occurred from geosmin and phenol, p-cresol and indol were detected from sediment/water samples. The others were detected as alcohols and fat acid compounds. Algae causing odor and taste were identified as Oscillatoria sp. and Synedra acus. 15 species of phytoplankton, a zooplankton, an eelworm and chironomus were identified in water/sediment sample.

• 공업화학
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• 제24권5호
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• pp.518-524
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• 2013

본 연구에서는 유전체 배리어 방전 플라즈마를 이용한 상수원의 이취미 및 독성물질 분해에 대하여 조사하였다. 이취미 물질로 지오스민(geosmin)과 2-methyl isoborneol (2-MIB)을 사용하였고, 독성물질로는 microcystin-LR (MC-LR), microcystin-RR (MC-RR), microcystin-YR (MC-YR), 그리고 anatoxin-a를 사용하였다. 플라즈마 반응기의 유입기체에 따른 분해 효율(반응시간 150 s 기준)은 지오스민의 경우 산소(100%) > 건조공기(96%) > 질소(5%) 순이었으며, 2-MIB의 경우에도 산소(100%) > 건조공기(94%) > 질소(2%) 순이었다. 이 결과는 이취미 물질이 주로 플라즈마 방전에 의해 생성된 산화성 성분, 특히 수명이 긴 오존에 의해 분해된다는 것을 나타낸다. 산소를 사용했을 때 지오스민과 2-MIB는 150 s 이내, microcystin류는 10 s 이내, anatoxin-a는 30 s 이내에 모두 분해되었다. 실제 호소수를 사용한 경우 증류수에서보다 이취미 및 독성물질의 분해효율보다 높게 나타났다.

• 한국환경보건학회지
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• 제32권4호
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• pp.262-267
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• 2006

DBPs and T&O(taste-and-odor) compounds in drinking water is one of main source to deteriorate water quality. So, these compounds can cause adverse health effects and result in many consumer complaints aesthetically. This experiments carried out to investigate the effect of boiling water on DBPs and T&O compounds in the tap water. THMs and TCM concentration were reduced by 91.3%, 88.9% after 5 min of boiling, respectively. It is certainly, resulted from volatilization of TCM. TCAA concentration decreased when the water was boiled, too. By contrast, the concentration of DCAA was increased with duration time from boiling-point. The reduction of TCAA from the boiled water can be attributed to chemical transformation like decarboxylation. T&O compounds such as geosmin and 2-MIB was effectively removed by boiling of water, resulting in the removal efficiency of 97.1%, 94.4% after 5 min of boiling, respectively.

• 상하수도학회지
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• 제20권6호
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• pp.849-855
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• 2006

Taste and odor (T&O) problems in drinking water supplies caused by eutrophication have become increasingly important because aesthetic qualities are the primary measures by which consumers estimate the quality of their drinking water. In order to overcome T&O problem, it is necessary to early detection method for T&O compounds before these compounds enter to water treatment plant. In this background, a early waming device for T&O compounds was developed and its performance tested under different operating condition. According to the experimental results on the adsorption efficiency of T&O compounds, when the raw water flowrate was 5 mL/min, the optimum stripping time and air flowrate were 5 hrs and 0.5 L/min, respectively. Comparison of activated carbon showed that foreign activated carbon was better than domestic activated carbon in terms of adsorption efficiency.

• 상하수도학회지
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• 제22권2호
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• pp.227-232
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• 2008

The masking effect of chlorine on algae-related taste and odor(T&O) compounds has long been an important issue for water suppliers. In this study, masking experiments with chlorine were performed on two kinds of treated water and one of raw water. After adding chlorine(0 to 0.8 mg/L) to water samples, odor intensity was evaluated by a newly developed sensory method(2-out-of-5 odor test) for three days along with the measurement of residual chlorine concentration. Even though the relationship between the residual chlorine concentration and odor reported by the sensory analysts was not always coincident, it was proved that residual chlorine more than a certain concentration could completely mask both added geosmin and naturally occurring T&O compounds. For the sand-filtered water spiked with 10 ng/L of geosmin, 0.12-0.18 mg/L of residual chlorine was necessary to achieve complete masking. In the case of GAC-filtered water, 10 ng/L of spiked geosmin was completely masked by 0.15-0.1 mg/L of residual chlorine. Combined ozone and GAC was not enough to treat raw water spiked with 300 ng/L of geosmin. In this experiment, sensory analysts were able to detect earthy or musty odors from the treated water. From a masking experiment with raw water taken from the Daechung Reservoir, it was found that fishy odor was more difficult to mask with chlorine than earthy odor. As the chlorine residual declined, the analysts began to notice the original odor and the fishy odor was noticed earlier than the earthy odor.

• 상하수도학회지
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• 제21권1호
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• pp.91-99
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• 2007

It is well-known that the presence of NOM (natural organic matter) in water has a negative effect on removing taste and odor compounds by activated carbon adsorption. Therefore, various means such as enhanced coagulation are applied to reduce the NOM. The presence of taste & odor compounds in drinking water even parts per trillion, is enough to generate customer dissatisfaction. Therefore, the aim of this study was to evaluate carbon usage rate (CUR) for conventional coagulation (CC) and enhanced coagulation (EC) in order to improve the efficiency of adsorption of taste and odor compounds. Also, Effect of CC and EC on molecular weight fraction and the early stage breakthrough of 2-MIB and Geosmin are evaluated. When the enhanced coagulation was adapted for pretreatment for activated carbon adsorption the operation period could be prolonged by 3.5~4 times. CUR for CC was about 2 times greater than CUR for EC and this means that EC has more adsorption capacity than CC. To analyze effect of EC and CC on breakthrough of 2-MIB quantitatively, adsorbed NOM mass was calculated based on unit mass of activated carbon. In the early stage breakthrough of 2-MIB, total adsorbed NOM was 23.72mg/g for CC and 34.56mg/g for EC. Therefore, it is shown that the early breakthrough term of 2-MIB and Geosmin was improved due to increased adsorbability. The low-molecular-weight NOM (500~2000Da) compounds were the most competitive, participating in direct competition with 2-MIB for adsorption site.

• Journal of Ginseng Research
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• 제23권4호
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• pp.211-216
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• 1999

온도와 시간을 달리하여 홍삼박을 볶음처리하여 얻은 분말과 수용성 추출액의 향기성분과 관능적 특성을 분석한 결과, $200^{\circ}C$에서 20분간 처리하였을 때 무처리 분말보다 정유성분의 양이 많았고, 향기성분은 7종의 pyrazin계 화합물을 비롯하여 29종의 화합물이 확인되었다. Panel에 의해 평가된 관능적 향미는 무처리구인 홍삼박 분말에서는 흙 냄새, 묵은 쌀 냄새, 비린내, 마른나무 냄새가 강하였으나, 볶음처리한 분말에서는 탄내, 구수한 냄새가 강하게 평가되었다. 볶음처리한 분말 $5\%$용액의 향은 무처리구에서는 비린내가 강하였으나, 처리구에서는 향기로운 냄새, 탄내, 누룽지 냄새, 마른나무 냄새가 강하였으며 비린내는 매우 약하게 평가되었다. $200^{\circ}C$에서 20분간 처리구에서 특히 커피와 같은 향미, 개운한 맛, 누룽지 냄새가 강했고, $2.5\%$ 용액에서는 개운한 맛, 떫은 맛이 강한 것으로 평가되었다. 볶음처리 시 생성된 이들 향미성분은 유리당과 aiginine함량의 급격한 감소에 의한 것으로 생각된다.

• 상하수도학회지
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• 제26권2호
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• pp.219-228
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• 2012

Problems due to the taste and odor in drinking water are common in treatment facilities around the world. Taste and odor are perceived by the public as the primary indicators of the safely and acceptability of drinking water, and are mainly caused by the presence of two semi-volatile compounds-2-methylisoborneol(2-MIB) and geosmin. Conventional treatment processes in water treatment plants, such as coagulation, sedimentation and chlorination have been found to be ineffective for the removal of 2-MIB and geosmin. Pulse UV system is a new UV irradiation system that is a non-mercury lamp-based alternative to currently used continuous wave systems for water disinfection. This study shows pulse UV system to be effective in treatment of these two compounds. Geosmin removal efficiency of UV process alone achieved approximately 70% at 10sec contact time. 2-MIB removal efficiency of UV only process achieved approximately 60% at 10sec contact time. The addition of $H_{2}O_{2}$ 7mg/L increased geosmin and 2-MIB removal efficiency upto approximately 94% and 91%, respectively.

• Preventive Nutrition and Food Science
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• 제3권1호
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• pp.15-21
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• 1998

Volatile flavor compounds in hydrolyzed blue mussel(HBM) produced by OptimaseTM APL-440, with untreated blue mussel(UBM) were compared. A total of 100 volatile compounds were detected in both HBM and YBM , consisting mainly of 25 aldehydes, 16 ketones, 17 alcohols, 8 nitrogen-containing compounds, 11 aromatic compounds, 8 terpenes, and 15 miscellaneous compounds. Levels of aromiatic compounds decreased after hydrolysis, whereas levels of 7 nitrogen-containing compounds increased. The compounds , 3-methylbutanal, (z)-4-heptenal, and (E,Z)-2-, 6-nonadienal , had the highest odor values in both samples. Total free amino acids in HBM were 21.89%(w/w) and increased by 3,4 times higher than UBM. glutamic acid and aspartic acid, having sour tastes, were the major taste-active compounds in HBM.