• Korean Journal of Food Science and Technology
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• v.46 no.1
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• pp.19-24
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• 2014

This study was carried out to identify the volatile organic compounds (VOCs) in polyethylene terephthalate (PET) bottles and to determine the extent to which VOCs migrate into mineral water during the bottling process and storage. A greater amount of nonanal and decanal was generated from the PET bottles than from the PET preforms. Benzene, ethylbenzene, nonanal, and vinyl benzoate were identified from the PET bottles when the incubation temperature of the headspace solid-phase microextraction (HS-SPME) sampler was set to 60, 80, and $100^{\circ}C$. As the incubation temperature increased, the concentrations of nonanal, vinyl benzoate, and decanal increased significantly. When the high-density polyethylene (HDPE) PET bottle caps were extracted with dichloromethane, the level of Irgafos 168 was found to be $206{\pm}20.1\mu}g/g$. The concentration of 2,4-di-tert-butylphenol in water was $4.80{\pm}0.2{\mu}g/L$. Therefore, it is necessary to avoid exposing PET and HDPE resins to high temperatures during the manufacturing process and storage of bottled water.

• Korean Journal of Food Science and Technology
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• v.36 no.6
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• pp.919-923
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• 2004

Effects of adding 0, 2, 4, 6, and 8% freeze-dried kimchi powder (FDKP) on kimchi snack quality were examined. Headspace volatile compounds of 4% FDKP snack, receiving highest overall preference in sensory evaluation results, were analyzed, and 26 compounds were identified, including 13 aldehydes, 3 sulfides, a ketone, an acid, a terpene, and 7 other compounds. Pearson correlation analyses were carried out to determine a correlation between the concentration of FDKP and the amount of each volatile compound. Acetaldehyde, propanal, dimethyl sulfide, dimethyl disulfide, acetic acid, and d-limonene showed correlation coefficients above 0.90; selective ion move (SIM) analysis also showed above 0.97 for highly correlated compounds. Results suggest that these compounds can be used as indicators fur kimchi flavor of FDKP snack.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.61 no.4
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• pp.242-250
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• 2016

Although rice has been cultivated as a major food crop for approximately 5,000 years, the interest of customers in 'scented rice' is a recent trend in the Korean market. As a part of developing a germinated scented rice variety, the newly bred scented rice variety 'Cheonjihyang-1 se' was germinated for 24 h, and changes in profiles of flavor-related volatiles, lipophilic phytonutrients, and fatty acids were investigated. The profiling of volatile compounds by using a headspace-gas chromatography-mass spectrometry (HS-GC-MS) revealed a total of 56 odor-active flavoring compounds; 52 at the pre-germination stage, 51 at the post-germination stage, and 47 common at both stages. The major flavoring compounds were nonanol and benzene, which constituted 11.5% and 6.6%, respectively, of the total peak area in pre-germinated rice, and 19.4% and 6.5%, respectively, in post-germinated rice. Germination induced an increase in 13 flavoring compounds, including 3,3,5-trimethylheptane and 1-pentadecene, which increased by 763 and 513%, respectively by germination. However, we observed a germination-induced decrease in most of the other flavoring compounds. Especially, the most important scented rice-specific popcorn-flavoring compound, 2-acetyl-1-pyrroline, showed 89% decrease due to germination. Furthermore, the germination of scented rice induced a decrease in the content of various phytonutrients. For example, the total contents of phytosterols, squalene, and tocols decreased from 207.97, 31.74, and $25.32{\mu}g\;g^{-1}$ at pre-germination stage down to 136.66, 25.12, and $17.76{\mu}g\;g^{-1}$, respectively at post-germination stage. The fatty acid compositions were also affected by germination. The composition of three major fatty acids, linoleic, oleic, and palmitic acids, increased from 36.6, 34.2, and 24.4%, respectively, at the pre-germination stage to 37.9, 36.9, and 20.7%, respectively, at the post-germination stage. All these results suggested significant changes in the flavor-related compounds and phytonutrients of the scented rice variety 'Cheonjihyang-1 se' during the process of germination, and subsequently the need for developing a more precise process of germination to enhance the flavor and nutritional quality of the germinated scented rice products.