• Journal of Food Hygiene and Safety
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• v.31 no.4
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• pp.258-263
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• 2016

The risks of sanitary indicative bacteria, heavy metals and chlorinated derivatives in 94 cases of sanitary wet towels used in food services (39 from sanitary wet towel treatment business, 55 from food services) were assessed in the present study. Lead was detected in the range of N.D.~0.41 mg/kg (75 cases were not detected), N.D.~0.25 mg/kg of arsenic (93 cases were not detected), N.D.~0.01 mg/kg of cadmium (7 cases were lower than limit of quantitation; 87 cases were not detected), 0.003 mg/kg ~ 0.09 mg/kg of mercury. And chromium (VI) was not detected from all samples. The level of lead was the highest among the tested heavy metals, and the highest concentration of lead was 0.41 mg/kg. However, it was only 2.1% of legal limit (less than 20 mg/kg). The average moisture content of the samples was 61.9% (50.0% ~ 77.0%) and it showed no relevance to the detection of bacterial counts. Escherichia coli was not detected. Bacterial counts were detected 43 cases and among them, 24 cases were exceeded the legal limit. It was verified that the packaging conditions of sanitary wet towel (whether it is packed by a piece or not and sealed or not) are critical factors to cause the germ contamination and cross contamination in the wet towels. The chlorinated derivatives (chlorites and chlorates) were detected in 17 (19.3%) out of 88 cases. The results would be used as preliminary information to establish the programs of "Safety education for manufacturers and public policy of safety".

• Journal of Food Hygiene and Safety
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• v.31 no.4
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• pp.250-257
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• 2016

This study was conducted to extract the factors affecting the microbial safety of leaf and stem vegetables in the high school foodservice and to provide information for supplying the safe foodservice menu. The lunch and dinner menu (1,945 data) of the total 6 high schools at the Central and the South Region in March, June, September, and December were collected. The frequency analysis and the multiple correspondence analysis (MCA) based on the 3 factors (potentially hazardous food (PHF), leafy and stem vegetables in the menu, the cooking methods) were conducted. The most frequent PHF was the menu of blanched vegetables, salads, seaweeds and fried chicken. The most frequent consumed leaf and stem vegetables were spinach, chive, lettuce, Western cabbage, perilla leaf, iceberg lettuce, chicory, leek and broccoli. MCA based on the leaf and stem vegetables, the region, and the cooking method (cooked/non-cooked) showed that garlic stem and spinach were more used in the Central Region, while water drop-wort were more used in the South Region. Iceberg lettuce, Bok choy and leek were included frequently in the PHF menu. Plant products frequently used in PHF menu requires the food safety system such as Good Agricultural Practice (GAP) to reduce the microbial risk. The menu database according to raw materials based on cooking methods (heating or mixing) as well as the development and verification of menu based on the microbial safety will be contributed to provide the safer foodservice menu.

• Journal of Food Hygiene and Safety
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• v.31 no.4
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• pp.227-249
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• 2016

Arsenic and its compounds vary in their toxicity according to the chemical forms. Inorganic arsenic is more toxic and known as carcinogen. The provisional tolerable weekly intake (PTWI) of $15{\mu}g/kg$ b.w./week established by the Joint FAO/WHO Expert Committee on Food Additives (JECFA) has been withdrawn, while the EFSA panel suggested $BMDL_{0.1}$ $0.3{\sim}8{\mu}g/kg\;b.w./day$ for cancers of the lung, skin and bladder, as well as skin lesions. Rice, seaweed and beverages are known as food being rich in inorganic arsenic. As(III) is the major form of inorganic arsenic in rice and anaerobic paddy soils, while most of inorganic arsenic in seaweed is present as As(V). The inorganic arsenic in food was extracted with solvent such as distilled water, methanol, nitric acid and so on in heat-assisted condition or at room temperature. Arsenic speciation analysis was based on ion-exchange chromatography and high-performance liquid chromatography equipped with atomic absorption spectrometry and inductively coupled plasma mass spectrometry. However, there has been no harmonized and standardized method for inorganic arsenic analysis internationally. The inorganic arsenic exposure from food has been estimated to range of $0.13{\sim}0.7{\mu}g/kg$ bw/day for European, American and Australian, and $0.22{\sim}5{\mu}g/kg$ bw/day for Asian. The maximum level (ML) for inorganic arsenic in food has established by EU, China, Australia and New Zealand, but are under review in Korea. Until now, several studies have conducted for reduction of inorganic arsenic in food. Inorganic arsenic levels in rice and seaweed were reduced by more polishing and washing, boiling and washing, respectively. Further research for international harmonization of analytical method, monitoring and risk assessment will be needed to strengthen safety management of inorganic arsenic of foods in Korea.

• Journal of Food Hygiene and Safety
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• v.25 no.2
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• pp.170-179
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• 2010

This study was conducted to investigate for mineral contents, total polyphenol compounds, betaine, choline and DPPH free radical scavenging activity of halophyte. The mineral concentrations of Salicornia herbacea (top part) were Na 100,006 mg/kg, K 1,385 mg/kg, Mg 6,263 mg/kg, Ca 2,750 mg/kg, Fe 90.4 mg/kg, Mn 98.9 mg/kg, Zn 33.3 mg/kg, Cu 3.4 mg/kg respectively. And Suaeda Japonica (top part) were Na 85,332 mg/kg, K 710 mg/kg, Mg 7,005 mg/kg, Ca 4,344 mg/kg, Fe 1,434.9 mg/kg, Mn 119.1 mg/kg, Zn 19.2 mg/kg, Cu 2.7 mg/kg respectively. The betaine contents of Salicornia herbacea (top part) were 15.09 mg/g and Suaeda Japonica (top part) were 14.64 mg/g. The choline contents estimated by the DBAP-choline derivatives of Salicornia herbacea (top part) were 20.9 mg/100 g, Salicornia herbacea (root) were 23.4 mg/100 g, Suaeda Japonica (top part) were 23.1 mg/100g and Suaeda Japonica (root) were 23.8 mg/100 g. Total polyphenol compounds of Salicornia herbacea (top part) were high 36.0 mg/g in growth phase. The DPPH radical scavenging activities of methanol extract Salicornia herbacea (top part) were high 90.1% in growth phase. The frozen dried powder of Salicornia herbacea (top part) 1 g was equal to Quercetin 30.26 mg, Rutin 42.65 mg, TBHQ 20.32 mg, BHA 25.86 mg, BHT 40.75 mg, Ascorbic acid 22.86 mg in DPPH radical scavenging activities.

• Journal of Food Hygiene and Safety
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• v.25 no.4
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• pp.402-409
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• 2010

The study was conducted to estimate the contents of heavy metal in commercial herbal medicines (1047 samples of 132 species) which were collected from markets in Seoul and to analyze the contents of heavy metals of herbal medicines by classifying them by parts. The samples were digested using microwave method. The contents of heavy metal (Pb, Cd, and As) and Hg were determined using Inductively coupled plasma-Mass spectrometer (ICP/MS). And the contents of Hg were obtained by Mercury analyzer. The average values of heavy metal in herbal medicines were as follows [mean (minimum-maximum), mg/kg]; Pb 0.870 (ND-69.200), As 0.148 (ND-2.965), Cd 0.092 (ND-2.010), and Hg 0.007 (ND-0.B7). And the average values of heavy metal by parts in herbal medicines were as follows [mean (minimum-maximum), mg/kg]; Ramulus 2.046 (0.065-4.474), Herba 1.886 (0.048-10.404), Flos 1.874 (0.052-5.393), Cortex 1.377 (0.011-4.837), Radix 1.165 (0.012-70.111), Rhizoma 1.116 (0.016-5.490, Fructus 0.838 (0.017-4.527), Perithecium 0.729 (0.013-4.953), Semen 0.646 (0.006-4.416). The average values of heavy metal of imported herbal medicines except Radix were higher than domestic ones. By decoction of herbal medicines exceeding the tolerances, average intake rates of Pb, As, Cd and Hg were obtained as 6.1%, 40.3%, 4.7%, and 2.2%, respectively.

• Journal of Food Hygiene and Safety
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• v.25 no.4
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• pp.303-309
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• 2010

This study was planned to monitor the change in the content of sulfur dioxide during the drying process of fresh vegetables. The analysis of sulfur dioxide was conducted by the Optimized Monier-Williams Method based on the Korea Food Code. The samples were kinds of vegetables which consisted of naturally-originated sulfur compounds (green onion, onion, cabbage, garlic, radish leaves, radish). Fresh vegetables (n = 182) and dried vegetables (n = 41) purchased from different local areas were investigated for the content of sulfur dioxide. The fresh vegetables were dried at 50~$60^{\circ}C$ using hot-air dryer. The moisture contents of dried samples were adjusted to keep 10 percents. The contents of sulfur dioxide in self-dried vegetables were 104.6 mg/kg in green onion, 75.4 mg/kg in onion, 129.1 mg/kg in cabbage, 197.6 mg/kg in garlic, 23.0 mg/kg in radish leaves and 52.5 mg/kg in radish, respectively. The increase of sulfur dioxide content according to the moisture content reduction was different from the expected. It means that the contents of sulfur dioxide can be altered by other factors except moisture contents. This results can be utilized as materials for the safe management of sulfites of dried vegetables.

• Journal of Food Hygiene and Safety
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• v.25 no.4
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• pp.354-359
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• 2010

In the present study, we investigated the chemical composition, antioxidant activities and nitrite scavenging ability in leaf and root of Youngia sonchifolia Max. The leaf powder contained 4.3% of water, 53.9% of crude carbohydrate, 21.6% of crude protein, 3.5% of crude fat and 16.7% of crude ash. The root powder contained 4.8% of water, 65.9% of crude carbohydrate, 17.4% of crude protein, 3.2% of crude fat and 8.7% of crude ash. The major mineral elements both in leaf and root powder were potassium, calcium, and magnesium. Contents of unsaturated fatty acids were higher than those of saturated fatty acids both in leaf and root powder. Total polyphenol and flavonoid contents of methanol extract in leaf were 3,922.4 mg/100 g and 1,903.2 mg/100 g respectively. In comparison, total polyphenol and flavonoid contents of methanol extract in root powder were 1,898.4 mg/100 g and 359.8 mg/100 g. The antioxidative activities of several solvents extract of leaf and root powder were investigated by measuring electron-donating ability using 1,1-diphenyl-2-picrylhydrazyl (DPPH). Of the each extracts, ethyl acetate extract of leaf and root powder showed relatively higher antioxidant activity; 94.3% in the leaf powder and 92.9% in the root powder. Nitrite scavenging ability was also highest in the ethyl acetate extract of leaf (45.4%) and root powder (28.8%). These results suggest that ethyl acetate extract of Youngia sonchifolia Max. can be used as a functional materials.

• Journal of Food Hygiene and Safety
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• v.28 no.4
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• pp.324-329
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• 2013

This study investigated and evaluated contamination levels of bacteria on tomatoes at farms stage to evaluate potential hazards associated with fresh tomatoes. A total of 170 samples, 90 samples from 5 sampling sites from 18 farms and 80 samples from 1 sampling site from 4 farms every month for four months, were analyzed to enumerate aerobic bacterial counts, coliforms, E. coli, Bacillus cereus, Staphylococcus aureus, Escherichia coli, E. coli O157:H7, Salmonella spp., and Listeria monocytogenes. Aerobic bacterial counts ranged from 0.48 to 6.15 Log CFU/g, with the lowest and the highest bacterial cell counts recorded for A site and E site, respectively. Thirty five percent of the samples from the E site contained more than 2 Log CFU/g. Six samples (6.6%) of 90 samples contained B. cereus less than 1 Log CFU/g. In addition, the contamination level of indicator bacteria and B. cereus in tomatoes were higher on March than on April, May and June (P < 0.05). S. aureus, E. coli, E. coli O157:H7, Salmonella spp. and L. monocytogenes were not detected in the tomato samples. The microbial contamination levels of tomatoes determined in this study may be used as the data for microbiological risk assessment.

• Journal of Food Hygiene and Safety
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• v.33 no.3
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• pp.200-206
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• 2018

This study was to investigate the optimal condition of mixture ratio for development of functional food ingredient from Sarcodon aspratus and rice bran. First, $^{\circ}Brix$ was measured along with extraction time. Five kinds of mixtures of Sarcodon aspratus and rice bran (10:0, 7:3, 5:5, 3:7, 0:10) were extracted in $95^{\circ}C$ water over a one-hour period and the extraction yield was evaluated. We further evaluated ${\beta}-glucan$ content, DPPH radical scavenging activity, ferric ion reducing antioxidant power (FRAP), total phenolic content and total flavonoids content. As a result, both Sarcodon aspratus and rice bran showed a constant $^{\circ}Brix$ after 45 minutes of extraction time. The content of ${\beta}-glucan$ was highest in the Sarcodon aspratus and rice bran mixture with a ratio of 3:7. As the ratio of rice bran increased in all mixtures, the antioxidant capacity also increased. In conclusion, to create a functional food ingredient the optimal mixing ratio of Sarcodon aspratus to rice bran is 3:7.

• Journal of Food Hygiene and Safety
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• v.33 no.3
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• pp.168-175
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• 2018

The use of microwave-assisted extraction and an acid-base clean-up process to determine the amount of methylmercury (MeHg) in marine products was suggested in order to improve the complicated sample preparation process. The optimal conditions for microwave-assisted extraction was developed by using a 10% NaCl solution as an extraction solution, setting the extraction temperature at $50^{\circ}C$, and holding for 15 minutes to extract the MeHg in marine products. A NaOH solution was selected as a clean-up substitute instead of L-cysteine solution. Overall, 670 samples of marine products were analyzed for total mercury (Hg). Detection levels were in the range of $0.0006{\sim}0.3801{\mu}g/kg$. MeHg was analyzed and compared using the current food code and the proposed method for 49 samples which contained above 0.1 mg/kg of Hg. Detection ranges of methylmercury followed by the Korea Food Code and the proposed method were $75.25(ND{\sim}516.93){\mu}g/kg$ and $142.07(100.14{\sim}244.55){\mu}g/kg$, respectively. The total analytical time of proposed method was reduced by more than 25% compared with the current food code method.