• Journal of Environmental Health Sciences
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• v.42 no.3
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• pp.160-168
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• 2016

Objectives: Materials coming into contact with food may result in the migration of chemical substances into the food. To protect consumers from exposure, Regulation (EU) No. 10/2011 specifies the use of standard migration tests. Polyethylene terephthalate (PET), widely used for food packaging materials, has drawn the attention of researchers because unwanted migration of PET into food might occur when consumers reuse packaging material. The aim of this study was to predict and develop a migration model for two components, acetaldehyde and butyraldehyde in PET, into food simulants under conditions of changing pH and solvents, such as those observed in fermented foods like kimchi or sauerkraut. Methods: Using a migration model based on Fick's second law of diffusion in one dimension, the migration of acetaldehyde and butyraldehyde from PET into a simulant of fermented food at $20^{\circ}C$ over 10 days was evaluated. The simulant for fermented food was modelled as 10% ethanol for three days, followed by 3% acetic acid for seven days. Results: The migration of acetaldehyde into the 10% ethanol was 0.36 times that of a simulated fermented food system, while that of butyraldehyde was 1.34 times greater. These results may have been influenced by the chemical interactions among the migrants, polymers and simulants, as well as by the solubilities of the migrants in polymers and simulants. Conclusion: Because food simulants have a limited capacity to mimic real food systems under the current migration model, an appropriate simulant and migration test should be considered in the case of increasing acidity. Furthermore, since the accuracy of the worst-case estimation of migration predicted by the current model is severely limited under changing food conditions, food simulants and their interactions should be further investigated with respect to conservative migration modelling.

• Journal of Korean Society for Atmospheric Environment
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• v.22 no.5
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• pp.679-692
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• 2006

The carbonyl compounds in the atmosphere belong to one of the regulatory pollutants for the malodor control designated by the Korean Ministry of Environment(KMOE). In the present study, the emission concentration levels of carbonyl compounds were measured along with a number of criteria odor pollutants from a total of 47 individual companies(June 2004 to January 2005). The results of our study showed that a number of carbonyl compounds(such as formaldehyde, acetaldehyde, acetone, and butyraldehyde) maintained significantly high mean concentrations of 298 to 372 ppb. In contrast, other carbonyl compounds were low enough with the mean valves of 0.54 to 19.1 ppb. It was found that except for such industries as metal production or leather processing, their emissions were generally quite significant. If the measured values were evaluated in terms of malodor intensity, butyraldehyde appeared to be the most significant contributor to the malodor release. According to the measurements made in strong source areas, it can be concluded that several carbonyl compounds(acetaldehyde, propionaldehyde, butyraldehyde, isovaleraldehyde, and valeraldehyde) are useful enough to diagnose malodor release from those source areas. It should also be addressed that a number of carbonyl compounds added newly as the result of malodor control legislation were not sensitive enough to diagnose malodor release from such sources.

• Journal of the Korean Society of Tobacco Science
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• v.11 no.2
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• pp.203-210
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• 1989

Leucine and isoleucine were reacted with glucose in a propylene glycol solution and volatile compounds produced from these reaction were analysed by gas chromatography and mass spectrometry. A total of 24 compounds were identified in the leucine reaction volatiles and the major components were 2-isopropyl-5-methyl-2-hexenal, methylbutyraldehyde PGA, butyraldehyde PGA, 5-methylfur-fural, isopropylmethylhexenal PGA and 2-acetylpyrrole. From the isoleucing reaction volatiles, 20 compounds were identified and the major components were methylbutyraldehyde PGA, butyraldehyde PGA and 2-acetylpyrrole. The amino acids chosen for this study were considered as giving fruity and cocoa aroma when heated with glucose.

• Bulletin of the Korean Chemical Society
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• v.30 no.10
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• pp.2208-2212
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• 2009

Oxidation of cycloalkenes with $O_2$ promoted by heterogeneous bis(acetylacetonato) cobalt (II) complex catalyst which can be recycled has been performed under mild conditions. It was found that $\beta$-ionone, cyclohexene, 1-methylcyclohexene, and $\alpha$-ionone were efficiently oxidized with $O_2$ in the presence of Co (II) complex and butyraldehyde at $55\;{^{\circ}C}$. A simple treatment of the resulting products led to epoxides as predominant products and a small amounts of allylic oxides, the chemoselectivity for the former being 82.1 - 90.8% with a 70.6 - 98.6% substrate conversion. On the other hand, oxidation of 1-phenylcyclohexene, 1-cyclohex-1-enylethan-1-one, $\alpha$-pinene, and $\beta$-pinene gave allylic oxides as major products.

• Journal of Environmental Health Sciences
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• v.23 no.4
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• pp.39-44
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• 1997

Propionaldehyde, n-Butyraldehyde, n-Valeraldehyde 수용액에 주파수 200 kHz, 출력 6.0 W/cm$^2$의 초음파조사후 그 분해반응에 관해 고찰했다. Aldehyde류는 초음파 조사에 의해 빠르게 분해되었고, 분해형태는 유사1차 반응을 나타내었다. 이들의 분해 속도는 Propionaldehyde

• Journal of Environmental Health Sciences
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• v.39 no.5
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• pp.418-425
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• 2013

Objective: This study was carried out for the purpose of identifying major substances contributing to the production of odor and evaluating the characteristic of odors. Methods: Complex odor and 17 odorous compounds were measured at 18 waste transfer stations located in Seoul. Results: The dilution ratio value of complex odor ranged from 4 to 30 times in the boundary layer of 18 waste transfer stations. At 6 measurement points among the 18 waste transfer stations, the dilution ratio values exceeded standards (15 times). When the results were evaluated in terms of their contribution to the formation of malodor, the patterns indicated that the highest concentration values in the residential waste disposal process were of i-valeraldehyde and acetaldehyde, while butyraldehyde and acetaldehyde accounted for a large proportion of odorous compounds from the waste recycling process. Conclusions: It was found that butyraldehyde and acetaldehyde were the primary compounds released from the food waste disposal process. Overall, aldehyde compounds were the greatest contributor to detectable odor intensity emitted at the waste transfer stations.

• Journal of Korean Society of Environmental Engineers
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• v.31 no.12
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• pp.1161-1168
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• 2009

This research was conducted on characteristic of offensive odors in Shihwa industrial complex. Result of blocks distribution of TVOC indicates that mechanic block, site D, was the highest concentration (74 ppb). Chemistry block, site A, was the second highest concentration (50 ppb). Also, mixed blocks, metal blocks and park etc. were measured almost similar concentration about 30 ppb, but mixed block, site F, was the place where concentrations were the smallest. Average of TVOC was shown about 35 ppb concentration. Aldehydes including acetaldehyde, butyraldehyde and hydrogen sulfide concentrations were prevalent among offensive odors in Shihwa industrial complex. Comparing the offensive odor intensity mostly about acetaldehyde, butyraldehyde and hydrogen sulfide which contain high offensive odor intensity showed results that sites A, B (chemistry block) and site D, I (mechanic block) site H (metal block) have showed the intensity over 1. In the case of acetaldehyde, relatively the high odor intensities over '2' were able to obtain in many cases. The correlation coefficient (r) for hydrogen sulfide was 0.91, so that high positive correlation exists between offensive odor intensity and the hydrogen sulfide element. Butyraldehyde also showed high positive correlation coefficient, as 0.82. Correlation coefficient of acetaldehyde that had the highest value as offensive odor substance was 0.62, had somewhat correlation with offensive odor intensity.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.6 no.3
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• pp.163-170
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• 2008

The reductive stripping of Np using a n-butyraldehyde (NBA) from loaded organic solution containing Np, which was oxidative-extracted in a system of a 30 % TBP/NDD-2M $HNO_3$ and O/A=2 containing 0.005 M $K_2Cr_2O_7$ as an oxidant of Np, was studied. The stripping yields of Np was increased with an increasing the NBA concentration, with a decreasing the nitric acid concentration of stripping solution and with a decreasing the reaction temperature. The apparent reductive stripping rate equation was shown by the following equation : $-d[Np]_{Org.}/dt$ = 1,524 exp(-2,906/T) $[NBA]^{0.91}\;[H^+]^{-0.92}[Np]_{Org.}$. At 1.04 M NBA and 2 M $NHO_3$, the stripping yield of Np and U was 70.1 %, and 7.1 %, respectively, and the separation factor of U over Np ($=D_U/D_{Mp}$) was about 30.4. Therefore, it was found that U and Np co-extracted in a system of TBP-$HNO_3$ could be effectively mutual-separated by the NBA.

• Journal of the Korean Chemical Society
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• v.15 no.3
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• pp.117-120
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• 1971

Possibility of two phase reduction of carbonyl compounds to the corresponding alcohols was studied. Thus the 0.5 M ether solutions of the representative carbonyl compounds were treated with alkaline stabilized sodium borohydride aqueous solution at room temperature. Butyraldehyde was reduced rapidly within one hr., whereas other aldehydes tested; heptaldehyde, benzaldehyde, and 1-naphthaldehyde were reduced in 6-12 hr. 2-Heptanone was reduced much slowly; 87% in 48 hr., however, acetophenone was reduced moderately; 92% in 12 hr. and cycloalkanones were reduced rapidly (cyclohexanone in 0.5 hr., and cyclopentanone in 3-6 hr.).

• Journal of the Korean Chemical Society
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• v.7 no.1
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• pp.85-90
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• 1963

The Knoevenagel reaction of fluorinated carbonyl compounds, 1,1,1-trifluoro-propanone-2-heptafluoro-butyraldehyde, 1,3-dichloro-1,1,3,3-tetrafluoro-acetone, tetradecafluoro-heptanone-4 and 2,2,2-trifluoro-acetophenone yielded fluorinated ${\beta},{\beta}$-dialkyl-${\beta}$-hydroxy acids. Dehydration of the acids do not give the olefinic acid in the case of the perfluorinated system and gave a lactone. From the consideration of electronic and steric effects a mechanismic path of the reaction via a carbanion intermediate was proposed for the reaction. Preparation of related derivatives are also described.