Hye-Young Seo

Volatile organic compounds of Angelica gigas Nakai, Korean medicinal herb

The study was performed to find out the profile of volatile flavor components from the aromatic medicinal plant, Angelica gigas Nakai. The volatile organic compounds of A. gigas Nakai were extracted by simultaneous steam distillation and extraction (SDE) method, and identified by gas chromatograph/mass spectrometric (GC/MS) analysis. A total of 116 compounds, including 40 hydrocarbons, 37 alcohols, 15 esters, 12 aldehydes, 7 ketones, and 5 miscellaneous were identified and quantified. Among them, 75 volatile organic compounds were detected which make up 90.52% of total volatile content. α-Pinene was detected as the prime volatile component which accounted for 30.89% of total volatile content and 2,4,6-trimethyl heptane, camphene, α-limonene, β-eudesmol, vervenol, α-murrolene, and sphatulenol were detected as the major components of A. gigas Nakai.

Determination of Essential and Toxic Elements in Vegetables from South Korea

ABSTRACT This study reports the determination of trace essential (Co, Cr, Cu, Se, and Zn) and toxic (Al, As, Cd, Hg, and Pb) elements in greenhouse tomatoes, peppers, and cucumbers from supermarkets of Seoul, Busan, Gangneung, Daegu, Daejeon, and Gwangju, South Korea using inductively coupled plasma mass spectrometry, inductively coupled plasma optical emission spectroscopy, and direct mercury analysis. The methods were validated by linearity, limits of detection and quantification, precision, accuracy, and recovery measurements that provided satisfactory results in all cases. Among the essential trace elements, Zn was found to have the highest concentrations (0.84–2.5 mg/kg) followed by Cu (0.21–0.62 mg/kg) and Cr (0.01–0.06 mg/kg). The mean concentrations (mg/kg) of the toxic elements were in the order Al > Pb > As > Cd > Hg for tomatoes and cucumbers and Al > Pb > Cd > As > Hg for peppers; all were below the permissible limits set by World Health Organization for human consumption. The estimated dietary intake, target hazard quotients (THQs), and hazard indices of the samples were within safe levels. The combined THQ values for the toxic elements in the vegetables were from 0.002 to 0.012 with significant contribution from arsenic, aluminum, cadmium, and mercury. The results of this study show that trace and toxic elements in the analyzed vegetables do not impose any serious health harmful effects for the population upon consumption.

Elemental Analysis of Sea, Rock, and Bamboo Salts by Inductively Coupled Plasma-Optical Emission and Mass Spectrometry

ABSTRACT The present study reports the determination of mineral nutrients and toxic elements of sea, rock, and roasted bamboo salts from China, India, France, Australia, Nepal, Argentina, and South Korea. Mineral nutrients including macro (Ca, K, Mg, Na, and S), micro (B, Cu, Fe, Sr, Mn, and V), trace (Ba, Be, Co, Cr, Ga, Li, Ni, Rb, Se, and Zn), and toxic (Al, Cd, Cs, In, Pb, and Tl) elements were analyzed by inductively coupled plasma-optical emission spectroscopy (ICP-OES) and ICP-mass spectrometry (ICP-MS). The detection limits were from 7.032 (Mg) to 13.915 (S) and 0.023 (Sr) to 0.228 (Ba) ng/g for ICP-OES and ICP-MS, respectively. The recoveries for fortified samples were from 91.3 to 107.6%. The concentrations of B, Ba, Be, Cs, Ga, In, Rb, Tl, and V were reported for the first time. In terms of mineral nutrients, the order was roasted salt > sea salt > rock salt. In addition, the only toxic element in roasted bamboo salt was aluminum. The concentrations of the elements were comparable to literature values and met regulatory guidelines. Roasted bamboo salt was shown to be a rich source of nutrients and provided the lowest concentrations of toxic elements. All salt types were shown to be safe for human consumption.

Analysis of Radiolytic Products of Lipid in Irradiated Dried Squids (Todarodes pacificus)

The lipid portion of dried squids (Todarodes pacificus) was extracted, and its hydrocarbons and 2-alkylcyclobutanones were separated using a florisil column. Both compounds were identified by gas chromatography and mass spectrometry and used to investigate the production of radiation-induced hydrocarbons and 2-alkylcyclobutanones. Concentrations of the hydrocarbons and 2-alkylcyclobutanones increased linearly with the radiation dosage. The major hydrocarbons in the irradiated dried squids were pentadecane and 1-tetradecene, which originated from palmitic acid. The amount of pentadecane was the highest among the radiation-induced hydrocarbons in the dried squids. The major 2-alkylcyclobutanone in the irradiated dried squids was 2-dodecylcyclobutanone, which was formed from the large amount of palmitic acid. 2-Tetradecylcyclobutanone, which may be produced from stearic acid in sample lipids, was also detected. Radiation-induced hydrocarbons and 2-alkylcyclobutanones were detected at > or = 0.5 kGy. These compounds were not detected in dried squids that were not irradiated. Radiation-induced hydrocarbons can be used as a detection marker for irradiated dried squids; however, the amount of 2-alkylcyclobutanones produced was not enough to be used as a marker. Radiolytic products of lipids, such as hydrocarbons or 2-alkylcyclobutanones. can be used to monitor food safety for consumers, ensuring proper irradiation labeling in foods and quarantine treatment in international trade.

Characteristics of Lotus and Lance Asia bell as Ingredients of Kimchi

The study of quality and salting characteristics of root vegetables other than Chinese cabbage was done to develop different kinds of Kimchi. The root vegetables lotus (Nelumbo nucifera) and lance Asia bell (Codonopsis lanceolata) were evaluated as main ingredients for Kimchi by measuring their physico-chemical and microbial properties. Salinity, pH, titratable acidity, reducing sugar, firmness, color change, moisture content, total viable counts, and lactic acid bacteria were investigated to identify adaptability for Kimchi. The initial pH of lotus and lance Asia bell showed 5.7 to 6.3 during the salting period, and the pH decreased with increasing salting periods. The reducing sugar contents of lance Asia bell showed 34.1 to 35.6 mg/g, which were significantly higher compared to lotus 3.2 to 3.4 mg/g. Titratable acidity also showed higher in salted lance Asia bell at 0.36 to 0.4%, while lotus showed 0.17 to 0.27%. Lactic acid producing bacteria increased in lance Asia bell during salting periods and reached after 48 hr of salting. However, no lactic acid bacteria were detected in lotus. As a result of this physico-chemical and microbial analysis, lance Asia bell was more suitable as an ingredient of Kimchi than lotus.

The rapid determination of PAHs in foods using ultra high performance liquid chromatography

Using a Hitachi LaChrom Ultra 2000U, a reverse phase ultra high performance liquid chromatography (u-HPLC) method was developed for the rapid quantification of 14 PAHs in foods. The proposed method for PAH analysis is based on solid phase extraction (SPE) cartridges; the determination was carried out by u-HPLC with fluorimetric detection. The method was very sensitive; PAH concentration levels were in a low ㎍/㎏ range and could be detected and quantified. Six samples of food were analyzed. Among PAHs, PHE was found in most of samples, the concentration ranging from 2.5 to 19.9 ㎍/㎏. The contents of benzo[c]fluorine (BCL), pyrene (PYR), benzo[a]anthracene (BaA), chrysene (CHR), benzo[b]fluoranthene (BbF), benzo[k]fluoranthene (BkF) were low at the ‘㎍/㎏’ level or were less than LOD.