• Preventive Nutrition and Food Science
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• v.16 no.4
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• pp.364-369
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• 2011

Levels of carbon dioxide gas, a metabolite of microbial growth, have been reported to parallel the onset of microbial spoilage and may be used as a convenient index for a packaged food's shelf life. This study aimed to establish a kinetic model of $CO_2$ production from perishable food for the potential use for shelf life control in the food supply chain. Aerobic bacterial count and package $CO_2$ concentration were measured during the storage of seasoned pork meat at four temperatures (0, 5, 10 and $15^{\circ}C$), and their interrelationship was investigated to establish a mathematical model. The microbial growth at constant temperature was described by using model of Baranyi and Roberts. $CO_2$ production from the stored food could be explained by taking care of its yield and maintenance factors linked to the microbial growth. By establishing the temperature dependence of the microbial growth and $CO_2$ yield factor, $CO_2$ partial pressure or concentration in package headspace could be estimated to a limited extent, which is helpful for controlling the shelf life under constant and dynamic temperature conditions. Application and efficacy of the model needs to be improved with further refinement in the model.

• Korean Journal of Medicinal Crop Science
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• v.12 no.2
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• pp.102-107
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• 2004

This study was carried out to establish an optimum method for identifying the volatile components of Magnolia ovobata Thunb. using the dynamic headspace (Purge & Trap) and simultaneous distillation and extraction (SDE) method. Between the two different identification analysis, the volatile components were more easily detected in the SDE than the Purge & Trap method. Among the identified volatile components, the 12 compounds were detected to have similar retention times and match quality within the 45 minutes in both identification methods. The maximum values of the major volatile components were detected differently by SDE and (Purge & Trap) method such as ${\alpha}-pinene$ (3.4, 18.2%), ${\beta}-pinene$ (3.5, 10.3%), l-limonene (5.2, 15.4%). These results indicated that the Dynamic Headspace (Purge & Trap) was much more reliable method for identifying the volatile components of Magnolia ovobata Thunb. as compared to the SDE method.

• Food Science and Biotechnology
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• v.16 no.1
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• pp.8-17
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• 2007

The main purpose of flavor research using conventional extraction methods, such as solvent extraction, distillation, and dynamic headspace, is to effectively extract, identify, and quantify flavor volatiles present in food matrices. In recent flavor research, the importance of understanding flavor release during mastication is increasing, because only volatiles available in the headspace contribute to the perception of food 'flavors'. Odor potency differs among flavor volatiles, and the physicochemical characteristics of flavor volatiles affect their release behavior and interaction with various food matrices. In this review, a general overview of flavor release and flavor-food interactions within frozen dessert systems is given with emphasis on chemical, physiological, and perceptual aspects. Chemical and sensory analysis methods competent for investigating such flavor-food interactions are illustrated. Statistical analysis techniques recommended for data acquired from such experiments are also discussed.

• The Korean Journal of Food And Nutrition
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• v.19 no.2
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• pp.161-168
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• 2006

The efficiency of six different extraction methods for the analysis of aroma components from pine needle(P. densiflora) was compared by gas chromatography-mass selective detector(GC-MSD). The six methods were dynamic headspace(DHS), reduced pressure headspace(RPHS), solid-phase microextraction(SPME), simultaneous distillation-extraction(SDE), supercritical fluid extraction(SFE) and pyrolysis distillation extraction(PDE). A total of 65 compounds were identified by using the six different extraction methods. These compounds are classified into six categories in terms of chemical functionality: 25 hydrocarbons, 16 alcohols, 9 carbonyls, 6 esters, 7 acids, and 2 ethers. The aroma compounds having low boiling point were more abundant in DHS, RPHS, and SPME extracts. On the other hand, the aroma compounds having high boiling point were more abundants in SDE, SFE and PDE extracts. The acid compounds were extracted by heat-based extraction methods such as SDE, SFE, PDE, but not by DHS, RPHS and SPME, which used neither solvent nor heat. The oxygenated terpens, hexanal, hexanol, and hexadienal were more abundant in DHS and RPHS extracts, compared with the other methods.

• Bulletin of the Korean Chemical Society
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• v.28 no.12
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• pp.2389-2395
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• 2007

Headspace solid phase trapping solvent extraction (HS-SPTE) and GC-MS was applied for the characterization of volatile flavors from fennel, anise seed, star-anise, dill seed, fennel bean, and Ricard aperitif liquor. Tenax was used for HS-SPTE adsorption material. Recoveries, precision, linear dynamic ranges, and the limit of detection in the analytical method were validated. There were some similarities and distinct differences between fennel-like samples. The Korean and the Chinese fennels contained trans-anethole, (+)-limonene, anisealdehyde, methyl chavicol as major components. The volatile aroma components from star anise were characterised by rich trans-anethole, (+)-limonene, methyl chavicol, and anisaldehyde. Additionally, principal component analysis (PCA) has been used for characterizing or classifying eight different fennel-like samples according to origin or other features. A quite different pattern of dill seed was found due to the presence of apiol (dill).

• The Korean Journal of Food And Nutrition
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• v.13 no.2
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• pp.118-124
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• 2000

Lipoxygenase(LOX) in soybeans is responsible for beany flavors which limit the wide utilization of soybeans to foods. This study was conducted to analyze beany flavor compounds of the normal Hwagkeumkong and LOX-deficient soybean cultivars, Jinpumkong which lacks L-2, L-3, and Jinpumkong 2 which lacks all L-1, L-2, L-3. Using the combination of dynamic headspace sampling and gas chromatography-mass selective detector(DHS-GC-MSD) for analyzing volatile compounds, hexanal and hexanol were identified in whole soy flour of all three soybena cultivars. Hwangkeumkong had more volatile compounds than Jinpumkong and Jinpumkong 2 in defatted soy flour. Hexanal and acetic acid were identified in soy milk of all three soybean cultivars but Hwangkeumkong had more volatile compounds than Jinpumkong 2. From the analysis with a static headspace sampling(SHS) and GC-MSD the major compounds were hexanal, acetic acid, 1-hexanol, and 1-octen-3-ol. The content of acetic acid was similar among three cultivars. But contents of hexanal and pentanal in Jinpumkong 2 were less than that of Jinpumkong and Hwangkeumkong. Using GC-FID, Jinpumkong 2 had less contents of hexanal and pentanol than Hwangkeumkong in whole soy flour and defatted soy flour. In this study, LOX-deficient soybean cultivars showed less hexanal, pentanol and other compounds than the normal Hwangkeumkong. However quite amount of beany flavor compounds were identified in Jinpumkong and Jinpumkong 2. So further studies are required to characterize LOX isozymes, to understand the mechanisms of beany flavors production, and to develop some other methods for removing beany flavor.

• Culinary science and hospitality research
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• v.19 no.3
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• pp.105-115
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• 2013

Maillard reaction flavors had been tried by using krill hydrolysate and precursors in order to develop Teriyaki sauce with the reaction flavors. Also, the study for applying krill to Teriyaki sauce had been tried by using krill instead of eel bones. To make boiled-type and grilled-type reaction flavors, krill hydrolysate was used with other precursors such as serine, glucose and glucosamine. In the dynamic analysis of headspace volatile compounds, 20 mL reaction flavor was analyzed by the combined system of purge & trap, automatic desorber, gas chromatography and mass selective detector. Three kinds of Teriyaki sauce were developed with reaction flavor, krill and eel bones, and their products were evaluated by 10 items of cooked vegetables, cooked potatoes, boiled shrimp, grilled shrimp, fishy smell, pungent aroma, burned smell, sweety aroma, chemical smell, mud smell and preference. In the results of headspace analysis, 35 and 33 volatile compounds were identified from grilled-type and boiled-type reaction flavors. Grilled-type had sulfur-containing, aliphatic compounds, alcohols, ketones, pyrazines, and other aromatic compounds, and grilled-type had aldehydes, furans, other nitrogen-containing compounds. In the sensory evaluation of Teriyaki sauce, the items of roasted shrimp and sweety aroma showed significant differences for grilled-type application to Teriyaki sauce. The above results show the possible application of grilled-type reaction flavor to Teriyaki sauce.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2003.09a
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• pp.458-461
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• 2003

Solid-phase microextraction (SPME) and gas chromatography/headspace techniques(HS) and flame ionization detection (GC/FID) have been combined for determination of very polar compounds in water, including the widely used gasoline oxygenates and by-products. A relatively simple extraction method using a CAR/PDMS(75${\mu}{\textrm}{m}$) SPME fiber was optimized for the routine analysis of gasoline oxygenates and by-products in groundwater and reagent water. A sodium chloride concentration of 25%(w/w) combined with an extraction time of 20 min provided the greatest sensitivity while maintaining analytical efficiency Replicate analyses in fortified reagent and groundwater spiked with microgram per liter concentrations of gasoline oxygenates and by-products indicate quantitative and reproducible recovery of these and related oxygenate compounds. Method dynamic range was 50$\mu\textrm{g}$ L-1 to 3000$\mu\textrm{g}$ L-1 for gasoline oxygenates and by-products.

• Analytical Science and Technology
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• v.28 no.6
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• pp.436-445
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• 2015

Amomi Fructus with anti-oxidative activity was chosen and essential oil was obtained by SDE (simultaneous distillation extraction), and 39 constituents were determined by GC-MS (gas chromatography-mass spectrometry). Major components were camphor, borneol acetate, borneol, D-limonene and camphene. Three solvent extracts such as hexanes, diethyl ether and methylene chloride from Amomi Fructus were obtained. These were analyzed by GC-MS and 4 more constituents were identified in addition to 39 components discovered in essential oil. Five major components such as camphor, borneol acetate, borneol, D-limonene and camphene were also detected, however the relative peak percents of those components were different from those of constituents in essential oil. To estimate the kind and the amount of materials evaporated at certain temperature and conditions from essential oil and solvent extracts, dynamic headspace apparatus was used and materials evaporated and trapped at certain conditions were analyzed by GC-MS. Recovery yield of SDE method from Amomi Fructus was measured by using camphor and standard calibration solution of camphor methanol solution and, the yield was 82.0%. Content of Hg was measured by mercury analyzer and contents of Cd, Pb, Cr, Mn, Co, Ni, Cu and Zn in Amomi Fructus, essential oils and solvent extracts were determined by ICP-MS (Inductively coupled plasma-mass spectrometer). Pb, Cd and Hg were measured in the concentration of 0.72 mg/kg, <0.10 mg/kg and 0.0023 mg/kg, respectively and these were below permission level of purity test. Contents of Mn, Cu and Zn in Amomi Fructus were 213 mg/kg, 8.29 mg/kg and 31.0 mg/kg, respectively and which were relatively higher than other metals such as Cr, Co and Ni. Metals such as Mn (0.65 ~ 9.08 mg/kg), Cu (1.16 ~ 4.40 mg/kg) and Zn (1.10 ~ 3.80 mg/kg) in essential oil and solvent extracts were detected. At this point it is not clear that the metals were cross-contaminated in the course of treating Amomi Fructus or metals were contained in Amomi Fructus. The influence evaluation toward biological model study of these metals in essential oil and solvent extracts will be needed.

• Korean Journal of Medicinal Crop Science
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• v.11 no.4
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• pp.274-278
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• 2003

The various plant organs of fennel (Foeniculum vulgare Mill.) were investigated to identify their volatile components using Dynamic Headspace (purge & trap). They showed slight differences concerning the volatile components both qualitatively and quantitatively. Results revealed that trans-anethole (12.65%) was the major compound in the leaf. The highest compound was ${\alpha}-pinene$ (28.78%), and trans-anethole (7.90%) was highly detected in the stem. The maximum values were 5.64, 4.59, 1.58, 1.51, and 1.04% for ${\alpha}-pinene,\;{\gamma}-terpinene,\;{\beta}-pinene$, 1,8-cineol and fenchone, respectively in the flower. However, very little trans-anethole was detected (0.27%) in the flower. From these results, it was suggested that the major components were different depending on the plant organs. However it was demonstrated that the related plant organs like flower-fruit and leaf-stem contained the similar components.