• Journal of Korean Society of Water and Wastewater
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• v.21 no.1
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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.

• Food Science of Animal Resources
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• v.33 no.4
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• pp.508-514
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• 2013

Taste-active compounds (e.g., amino acids and nucleotides) play an important role in contribution to the gustatoty sensation of food. The current study aimed to examine the differences in taste-active compounds between different beef muscles, breeds and aging periods. We have chosen the longissimus dorsi and semitendinosus muscles of Hanwoo breed and longissimus dorsi muscle of Angus breed for the investigation of the aforementioned compounds. Hanwoo muscles were aged for 7 or 28 d, and Angus samples were aged for 28 d at $4^{\circ}C$. Results revealed that 8 out of the 18 detected free amino acids (FAA) showed significant (p<0.05) differences between the two Hanwoo muscles. Twelve FAAs showed aging effect (p<0.05) in which the amounts of 8 FAAs significantly increased as aging time increased. Inosine 5-monophosphate (IMP), hypoxanthine (Hx) and inosine showed significant (p<0.05) differences between the Hanwoo muscles, aging resulted in an increase in amounts of these nucleotides. Hanwoo beef had significantly (p<0.05) higher total amount of sweet amino acids than the Angus ones in that 15 amino acids showed differences (p<0.05) between the two breeds. Amounts of guanosine 5-monophosphate (GMP) and Hx were significantly higher (p<0.05) for Angus beef. Current study indicated that muscle type, breed and aging period had large variations in free amino acid and nucleotide contents, which may subsequently affect the taste attributes of cooked beef.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.13 no.3
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• pp.115-119
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• 1980

Snakehead, Channa argus, is one of the most palatable fresh-water fishes in Korea; however, relatively little is known about the characteristics of taste. The present study was undertaken to analyze the proximate composition as well as the taste compounds of dorsal muscle of Korean snakehead. In the dorsal meat, glycine, taurine, alanine and lysine were abundant. Among these, glycine was the most dominant, occupying $63\%$ of total free amino acid. The amount of IMP was $2.78{\mu}mole/g$ and those of another nucleotides and their related compounds were not so high as compared to that of IMP. About $43\%$ of the total extractive-N was total creatinine-N. But the content of betaine-N was very low, occupying only $0.8\%$ of the total extractive-N and TMA-N and TMAO-N were trace in content. In snakehead, the sum of the nitrogen in these constituents amounted to nearly $80\%$ of total extractive nitrogen.

• Journal of the Korean Society of Food Science and Nutrition
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• v.24 no.2
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• pp.274-279
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• 1995

Seasonal variation of the taste components such as free amino acids, nucleotides, quarternary ammonium bases, and guanidino compounds in warty sea squirt(S. clava) were determined bimonthly from April to October for its food quality contributed in Korean seafood dishes. Fifty to sixty two percentage of the extractable nitrogen was free amino acids, and mainely it composed of taurine, proline, glutamic acid, glycine and glycinebetaine. Among the various taste component, betaine's level was somewhat higher(11~15%) and nucleotides related compounds also followed(5~8%). Most of nitrogenous compounds in the extractives reached to a maximum value in June and AMP content was relatively higher than the other nucleotides. The major organic acids were composed of succinic acid, malic acid, lactic acid and pyroglutaric acid in S. clava. The result of omission test suggested that the taste of S. clava is mainly attributed to free amino acids, betaines, nucleotides and non-volatile organic acid in order.

• Journal of Korean Society of Water and Wastewater
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• v.26 no.2
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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.

• Journal of Nutrition and Health
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• v.10 no.4
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• pp.97-103
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• 1977

Changes of free amino acids as taste compounds during the fermentation of oyster were analyzed by amino acid autoanalyzer. In fresh oyster, taurine, glutamic acid and alanine were abundant amino acids and the amounts of taurine (731mg%, on moisture and salt free base), glutamic acid (365mg%) and alanine (345.4mg% ) were 63.8% of the total free amino acids. Cystine, isoleucine, phenylalanine, leucine and histidine were detected as less abundant free amino acids and the amount of those amino. acids ranged from 5. 5mg% (cystine) to 32.9mg% (histidine). The free amino acids analyzed in this experiment were not changed in composition hut changed in amounts during 124 days of fermentation. Aspartic acid and leucine were continually increased during 124 days of fermentation. Lysine, histidine, threonine, serine, glutamic acid, tyrosine and phenyalanine were increased unlit 68 days of fermentation and than decreased gradually. The increase of arginine, glycine, valine and isoleucine were fluctuated. Taurine were dramatically decreased during the 124 days of fermentation. It is believed that glutamic acid, alanine, lecuine, serine, Iysine and threonine play an important role as taste compounds in fermented oyster because those amino acids were most abundant in fermented oyster.

• Journal of the Korean Society of Food Science and Nutrition
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• v.28 no.2
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• pp.312-318
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• 1999

Volatile compounds in salt fermented anchovy on the market were analyzed by vacuum simulta neous distillation solvent extraction/gas chromatography/mass spectrometry/olfactometry(V SDE/ GC/MS/O) and aroma extract dilution anlaysis(AEDA). Predominant odorants(Log3FD$\geq$8) in sample were ethyl methylbutanoate(candy like/sweet) and 2 ethyl 3,5 dimethylpyrazine(nutty/baked potato like). Besides these compounds, 6 odorants such as ethyl 3 methylbutanoate(sweet/floral/ candy like), 3 methylbutanal(dark chocolate like), (Z) 4 heptenal(rancid/fish like), (methylthio) propanal(soy sauce /baked potato like), (E,Z) 2,6 nonadienal(melon /cucumber like) and (E,E) 2,4 decadienal(fatty/cooked soybean like) were potent in odor value of salt fermented anchovy. Seven amino acids having high taste value in sample were glutamic acid, aspartic acid(sour and umami taste), lysine, alanine(sweet), histidine, valine, and methionine(bitter).

• Journal of Korean Society of Water and Wastewater
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• v.20 no.5
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• pp.719-726
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• 2006

Adsorption isotherms and kinetics for taste and odor (T&O) compounds and natural organic matters (NOMs) were performed to evaluate the impacts of activated carbon particle size on coagulation and adsorption. Adsorption capacities for iodine, T&O compounds, and NOM of all the activated carbons under #325 mesh were more excellent than those of virgin activated carbons. Small activated carbon particles were more rapidly adsorbed low molecular weight T&O compounds in the water, while those were slowly adsorbed high molecular weight NOM. When the activated carbon and alum were added simultaneously, the adsorption capacity for organics was better than alum was added alone.

• Food Science of Animal Resources
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• v.20 no.1
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• pp.64-71
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• 2000

The volatile flavour compounds such as acetaldehyde, acetone, ethanol, diacetyl and acetoin were detected by gas chromatography in adlay yoghurt during fermentation and storage period at 4 $pm$1$^{circ}C$, but acetoin was trace. The contents of acetaldehyde of adlay yoghurt showed maximum immediately after fermentation and decreased significantly(P<0.05) with storage period and were in order of adlay yoghurt fermented with YC-380, ABT-D and ABT-4. The contents of acetone were shown similar trend to acetaldehyde and those of adlay yoghurt fermented with YC-380, ABT-4 and ABT-D, decreased rapidly from 6 days, 9 days and 12 days of storage, respectively. The contents of ethanol increased during the storage period and those were significant differences(p<0.05) between 6 days and 9 days of storage period in control and treatments. The contents of diacetyl were detected in control and treatments at 9 days of storage and increased slightly during the storage period. The contents of volatile flavour compounds of T1 showed similar to that of control and slightly high compared to those of treatments, and decreased gradually with increasing the level of addition of adlay in treatments. The taste, flavour and texture of T1 immediately after fermentation and during the storage period at 4$\pm$1$^{\circ}C$ were slightly higher than those of control and treatments. The scores of sensory evaluation of treatments except T1 were lowered significantly(p<0.05) with increasing level of addition of adlay. Adlay yoghurt fermented with YC-380 and ABT-4 and ABT-D were superior to both of taste and flavour, and texture, respectively. From the results mentioned above, the addition of taste and flavour, and texture, respectively. From the results mentioned above, the addition of adlay at 1% (w/v) level in skim milk substrate were suitable for quality of adlay yoghurt such as volatile flavour compounds and sensory property.

• Food Science of Animal Resources
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• v.40 no.5
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• pp.772-784
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• 2020

This study was performed to investigate the effects of taste-related compounds and antioxidatve profiles of retorted samgyetang made from fresh and dried Cordyceps militaris (C. militaris) mushrooms. A total of 48 carcasses were prepared from commercial broilers (CB; Ross, 4 weeks old) and randomly distributed into eight different treatments. Each treatment group consisted of 6 chicken carcasses made with the addition of broth in different condition and concentration of C. militaris mushrooms. The addition concentration was based on the broth volume (v/w) under either fresh or dried conditions ranging from 0% as a control to 1%, 2%, and 3% of C. militaris mushrooms. C. militaris mushrooms contributed to an improvement of meat tenderness and the antioxidative profile that led to a greater suppression of lipid oxidation. The addition of C. militaris mushrooms at 2% could also enrich the flavor and taste-related compounds, particularly the increase in 5'-AMP and umami-related free amino acid compounds, L-aspartic acid and L-glutamic acid. Different addition forms of C. militaris mushrooms, particularly fresh or dried mushrooms, had only small effects on bioactive compounds, where the dried addition could possibly enrich samgyetang broth with higher cordycepin and adenosine contents than the fresh addition. Besides, the addition of C. militaris mushrooms in the dried form could also contribute to a higher antioxidative profile. Eventually, the addition of C. militaris mushrooms with a minimum addition of 2% contributed to an improvement of meat quality, antioxidative profile and flavor improvement of samgyetang.