• Journal of Life Science
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• v.19 no.9
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• pp.1333-1336
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• 2009

The purpose of this study was to characterize the aromas of rose tea and rosehip tea. Aroma compounds were extracted by simultaneous distillation and extraction method using a Likens and Nickerson's extraction apparatus. The concentrated aroma extracts were analyzed and identified by GC and GC-MS. Thirty-eight compounds, including phenylethyl alcohol, citronellol, menthol, menthone, linalool and geraniol, were isolated and identified in rose tea. Thirty-six compounds, including menthol, $\alpha$-anethole, $\alpha$-terpinolene, menthone, linalool and 6-methyl-5-heptene-2-one, were isolated and identified in rosehip tea. Large amounts of phenyl ethyl alcohol and citronellol were found in rose tea, while large amounts of menthol and $\alpha$-anethole were found in rosehip tea.

• Asian-Australasian Journal of Animal Sciences
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• v.25 no.3
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• pp.435-446
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• 2012

The present study identified volatile flavor components of Hanwoo longissimus muscle and other Korean foods (Doenjang, Chungukjang, sesame oil) and their traits were compared in relation with flavor precursors that include fatty acids and protein degradation products. Hanwoo longissimus muscle was purchased from a commercial abattoir while the other foods were sampled from three separate households. The results showed totals of 68 ($9.94{\mu}g/g$), 60 ($15.75{\mu}g/g$), 49 ($107.61{\mu}g/ml$) and 50 ($7.20{\mu}g/g$) volatile components for Doenjang, Chungukjang, sesame oil and Hanwoo beef longissimus, respectively (p<0.05). Aldehydes were the most predominant components in beef, but alcohols, acids and esters, and pyrazines are probably the major contributors to the flavor characteristics of other foods. SDS-PAGE revealed that beef longissimus muscle and Doenjang showed higher protein degradation than other foods which could be likely related to chiller ageing and ripening process. The total polyunsaturated fatty acids were approximately 50, 60, 41 and 5% for Doenjang, Chungukjang, sesame oil and beef longissimus muscle, respectively. Based on the mechanism(s) of generation of the volatile compounds and the chemical composition of each food sample, differences and traits of volatile flavor components among the four food types are likely due to fatty acid profiles, proteolytic activity and processing conditions. Aroma intense compounds like pyrazines and sulfur-containing compounds were limited in cooked beef in the current experimental condition (i.e., relatively low heating temperature). This suggests that higher heating temperature as in the case of roasting is needed for the generation of high aroma notes in meat. Furthermore, proteolytic activity and stability of fatty acids during ageing have a great influence on the generation of flavor components in cooked beef.

• Asian-Australasian Journal of Animal Sciences
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• v.33 no.8
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• pp.1339-1351
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• 2020

Objective: It is well recognized that beef cuts from a low quality grade are usually associated with tougher, drier and less flavorful. Thus, the present study aimed at investigating the combined effects of postmortem ageing and sous vide (SV) cooking followed by oven roasting or blowtorching on the eating quality of low quality grade Hanwoo beef striploins. Methods: Hanwoo beef striploins (quality grade 3) obtained from 36 month-old Hanwoo steers were used, and the samples were chiller aged for 0 and 14 d at 4℃. After ageing, the samples were prepared into 2.5-cm steaks which were then SV cooked at 55℃ for 5 h and then raised to 60℃ for 1 h, and thereafter the SV-cooked the steaks were further roasted in oven for 20 min (SV+OV) or blowtorched (SV+TC) for 2 min. The cooked samples were analyzed for microbiological quality, browning index, Wanrner-Bratzler shear force (WBSF), aroma flavor compounds and sensory properties. Results: The SV cooking significantly reduced the WBSF values in beef samples (p<0.05). Blowtorching after SV cooking led to a browner surface of the beef steaks (p<0.05). The samples treated with SV+OV or SV+TC exhibited higher levels of Maillard reaction-derived aroma flavor compounds such as; pyrazines and sulfur-containing compounds compared to those just SV cooked. More especially, the SV+OV- or SV+TC- treated samples presented significantly higher flavor and overall acceptability scores compared to those just SV cooked (p<0.05). Ageing beef for 14 d significantly improved the tenderness by reducing the WBSF and increasing the tenderness scores. Conclusion: Thus, the combination of postmortem ageing and SV cooking followed by additional treatments (blowtorching or oven roasting) could be used to improve the eating quality especially tenderness and flavor as well as overall acceptability of low grade Hanwoo beef.

• Food Science and Biotechnology
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• v.18 no.5
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• pp.1288-1292
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• 2009

Volatile flavor compounds were isolated from the flowers of Chrysanthemum indicum L. (gamguk) produced in Korea and China by the hydro distillation, and were analyzed by gas chromatography-mass spectrometry (GC/MS). The yield of oils from Korean and Chinese gamguk were 2.0 and 0.5%(v/w), respectively. Sixty-three volatile compounds of Korean gamguk representing 89.28% of the total peak area were tentatively identified, including 35 hydrocarbons, 12 alcohols, 6 ketones, 3 esters, 5 aldehydes, 1 oxide, and 1 miscellaneous component. Thirty-six volatile components of Chinese gamguk constituted 58.15% of the total volatile composition were tentatively characterized, consisting of 19 hydrocarbons, 7 alcohols, 2 ketones, 2 esters, 4 aldehydes, 1 oxide, and 1 miscellaneous component. The predominant components of Korean oil were ${\alpha}$-pinene, 1,8-cineol, and chrysanthenone. Whereas, camphor, ${\alpha}$-curcumene, and ${\beta}$-sesquiphellandrene were the main aroma compounds of Chinese gamguk.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.19 no.1
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• pp.31-56
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• 1993

The characteristic aroma of Gardenia Absolute Oil made from Gardenia Jasminoides Ellis was investigated by GC and GC-MSD and by sensory evaluation The method of GC Analysis was used Double Column System by Carbowax 20M /SPB-1 of Pola/nonPola columns. And the result data of analysis was checked automatic Relent ion Indexs Match System by GC Workstation. A total of 51 compounds were identified in Gardenia Absolute Oil, including t entatively erstimated 9 compounds. The major components were Linalool, Farnesene of various form, Jasmin Lactone, Gamma undecalactone and Cis-3-hexone derivatives.

• Journal of the Korean Society of Food Science and Nutrition
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• v.27 no.5
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• pp.846-851
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• 1998

Characteristics of chunggugjang fermented by Bacillus subtilis DC-2, a pigment producing bacterium, were investigated. More water soluble browning materials were produced with fermentation time. The pH was gradually alkalized. The contents of amino nitrogen were extraordinarily increased with fermentation time. Both strength and hardness were gradually decreased during fermentation. Total 30 volatile compounds were identified in the chunggugjang fermented by B. subtilis DC-2. The pyrazines were detected more than any other compounds. The good aroma of the chunggujang fermented by B. subtilis DC-2 was considered to be contributed by tetramethylpyrazine, trimethylpyrazine, 1-octen-3-ol, 2, 5-dimethylpyrazine and guaiacol.

• Applied Biological Chemistry
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• v.46 no.1
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• pp.23-27
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• 2003

Lipoxygenase is the enzyme responsible for the formation of $C_6$-alcohols and $C_6$-aldehydes ($C_6$-compounds), which are well blown contributors to various types of 'green odor' In green tea. Changes in lipoxygenase activity and volatile compounds of green tea leaves were monitored daily during early growing season. The enzyme activity was spectrophotometrically measured using linoleic acid as a substrate. The volatile compounds were extracted through Solid Phase Micro-Extraction, and were subjected to GC and GC-MS analyses. Results showed that lipoxygenase activity and levels of $C_6$-compounds concomitantly increased or decreased during the early growing season, probably caused by the fluctuation in the daily temperature; increase in temperature led to the increase in enzyme activities and $C_6$-compound levels, whereas leaves plucked too early had low volatile compound levels. In this study, optimum plucking time of tea leaves for the production of high quality green tea with a wellbalanced aroma was determined.

• Journal of Life Science
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• v.24 no.12
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• pp.1325-1329
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• 2014

Gugija (Lycii chinese Miller) is traditionally consumed as a Chinese medicinal material in food, tea, or alcoholic beverages. Gugija has beneficial healthy components, but it produces an off-flavor during storage. This study compared the flavor components of fresh-dried Gugija and stale-dried Gugija. The flavor compounds in one fresh sample (sample 1) and one stale sample (sample 2) were extracted by the simultaneous distillation and extraction method. The concentrated aroma extracts were analyzed and identified by gas chromatography-mass spectrometry. Forty-five compounds, including 17 aldehydes, 8 alcohols, 6 terpene compounds, 4 esters, 3 ketones, and 3 pyrazines, were isolated in sample 1. Thirty-four compounds, including 12 aldehydes, 3 alcohols, 5 terpene compounds, 2 esters, 3 ketones, 3 pyrazines, and 1 acid, were isolated in sample 2. The main aroma components of sample 1 were 2-methyl butanal, 2-methyl propanol having sweet odor, and hexanal, (Z)-3-hexenol having grass odor, and phenyl acetaldehyde, benzyl alcohol having floral odor, and alkyl pyrazines having nutty odor. These compounds were decreased in sample 2, and several compounds containing isovaleric acid, which has a disagreeable, rancid-cheese odor were found newley.

• The Korean Journal of Mycology
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• v.19 no.4
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• pp.292-298
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• 1991

Volatile aroma concentrates of Pleurotus sajor-caju which stored at $20^{\circ}C$ incubator and cold room were obtained by simultaneous distillation-extraction method. The volatile components were identified by combined capillary gas chromatography-mass spectrometry and comparison of retention data on GC of those authentic compounds. Storage at room temperature resulted in significant decreased in their total aroma contents, whereas little changes at cold storage foured, even though appreciable changes were observed in GC pattern between the control and stored samples. Of 38 components identified, ${\delta}-decalactone$ increased while rest of the volatiles decreased rapidly during storage at room temperature, but at cold storage 2-methyl butanal, 1-octen-3-ol, cis,cis-1,5-octadien-3-ol and pentadecanoic acid decreased while 3-octanone, 1-octen-3-one, 3-octanol and 5-undecanol increased with the storage time. The weight losses and organoleptic properties changed extremely by the storage under room temperature, on the other hand, slight changes were found in cold storage.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.37 no.5
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• pp.366-371
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• 2004

Powder and liquid products of the seasoned and smoked fish were manufactured with small-sized skipjack tuna (Euthynus pelamis) captured in the East Sea, Korea. The property changes of nucleotides and their related compounds, amino acid, and sensory attribute during storage were analyzed. IMP content was the highest among the nucleotides and their related compounds followed by inosine in both powder and liquid products. Nucleotides and their related compounds of the powder product increased slightly as storage period increased, while those of liquid product were constant. Glutamic acid $(15.6{\%})$, aspartic acid $(10.7{\%})$, and lysine $(9.3{\%})$ were major amino acids of the power product, while histidine $(36.2{\%})$ and taurine $(10.6{\%})$ were high in the liquid product. Free amino acid contents of liquid product increased during storage periods. There was no significant difference In the concentration of nucleotides and their related compounds, and composition of free amino acid between the products with/without liquid smoke. Aroma and acceptance were good in both products, while bitterness and sweetness were poor.