• Food Science and Preservation
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• v.13 no.1
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• pp.50-54
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• 2006

The identification characteristics of inadiated dried onion and garlic at 1, 4 and 7 kGy were investigated by analyzing their photostimulated luminescence (PSL), thermoluminescence (TL) and electron spin resonance (ESR). The PSL results showed that the photon counts of non-irradiated dried onion were less than 700 (negative) and those of irradiated samples at 1kGy or more were over 5000 (positive), making it possible to discriminate non-irradiated onions from irradiated ones. However, the intermediate counts (700-5000) were observed in irradiated garlic at 1 and 4 kGy, even though positive counts were measured in 7 kGy group. Radiation-induced TL glow curves $(TL_1)$ were measured at $150^{\circ}C$ range in both irradiated onion and garlic samples at 1 kGy or more, which could identify irradiated groups. Furthermore, determination of TL ratios $(TL_1/TL_2)$ for both samples could verify the above results. It was found, however, that ESR spectroscopy was not suitable for the detection of irradiated dried onion and garlic.

• Korean Journal of Food Science and Technology
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• v.39 no.2
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• pp.114-121
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• 2007

The purpose of this study was to investigate 253 kinds of pesticide residues in 58 commercial dried agricultural products in Seoul. The determinations of the pesticide residues were performed using multiresidue methods and were carried out by a gas chromatography-nitrogen phosphorus detector (GC-NPD), an electron capture detector ($GC-{\mu}ECD$), a mass spectrometry detector (GC-MSD) and high performance liquid chromatography-ultraviolet detector (HPLC-UV), and a fluorescence detector (HPLC-FLD). The pesticide residue detection rate in the commercial dried agricultural products was 24.1% (14 of 58 samples). Twelve pesticide residues without maximum residue limits (MRLs) were detected. In the vegetable groups, the frequency of pesticide residues was found to be in the increasing order of dried fruiting vegetables > dried leafy vegetables > dried stalk and stem vegetables. The pesticides used on dried red pepper in the dried fruiting vegetables were varied (7 kinds) and numerous (4 of 8 samples). The pesticide types detected in the commercial dried agricultural products were in the order of pyrethroid > organochloride > organophosphorus and insecticide > fungicide > herbicide ${\cdot}$ nematicide. The primary pyrethroid pesticide detected was cypermethrin. According to the producing areas of products, large numbers of pesticide residues were found in the order of Korea, China, North Korea, USA, and Vietnam.

• Journal of Food Hygiene and Safety
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• v.31 no.6
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• pp.393-398
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• 2016

The objective of this study was to isolate pathogenic Escherichia coli from fresh vegetables with selective media and Petrifilm, and identify a suspicious colony using biochemical identification. Twenty gram of lettuce, twenty gram of cabbage and ten gram of sprout were prepared, and a 5-strain mixture of pathogenic E. coli (Enterohemorrhagic E. coli NCCP11142, Enterotoxigenic E. coli NCCP14037, Enteropathogenic E. coli NCCP14038, Enteroaggregative E. coli NCCP14039, Enteropathogenic E. coli NCCP15661) was inoculated to obtain 1, 2 and 3 log CFU/g. Eighty to ninety milliliter of buffered peptone water (BPW) was placed and pummeled for 60 s. As a results, the Petrifilm method was all positive, but enrichment method of qualitative analysis was negative except for 3-log CFU/g inoculated lettuce. Regarding biochemical identification of pathogenic E. coli, the identification rates were dependent on type of methods and vegetables; lettuce: API 20E 100% (44/44), Microgen GNA 100% (44/44) and Food System 66.7% (10/15), cabbage: API 20E 64.7% (22/34), Microgen GNA 50% (16/32) and Food System 60% (9/15), sprout: API 20E 65.1% (28/43), Microgen GNA 62.3% (27/43) and Food System 53.3% (8/15). These results could be useful in determining an appropriate method to detect pathogenic E. coli in fresh vegetables.

• Journal of the East Asian Society of Dietary Life
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• v.24 no.1
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• pp.28-41
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• 2014

The distinctive physiological effect of dietary fiber in the body were studied according to contents and characteristics of each fiber component. In the present study, the composition of fiber in vegetables was investigated, and the effect of heat treatments on fiber content was studied. Contents of total pectin were 0.89~2.75 g/100 g on dry weight basis, with most contents from 1~2 g/100 g. The hot water soluble pectin (HWSP) content of vegetables ranged from 0.33~0.98 g/100 g, sodium hexametaphosphate soluble pectin (HXSP), from 0.29~0.81 g/100 g and HCl soluble pectin(HCLSP), from 0.30~1.40 g/100 g. HCLSP showed the greatest variation according to the type of vegetables. Every vegetable types showed similar contents of these three pectic fractions. Fiber contents of vegetables ranged from 8.8~23.8% for cellulose, 0.6~10.6% for hemicellulose, 1.0~5.2% for lignin, 10.9~25.4% for acid detergent fiber (ADF) and 11.8~31.9% for neutral detergent fiber (NDF) on dry weight basis. Especially, peppers showed higher contents of NDF than the other vegetables. It was found that a great portion of NDF, which is total insoluble dietary fiber, was composed of cellulose since cellulose constituted 63% of NDF. Heat treatment reduced total pectin content in all vegetables regardless of the heating methods and the greatest reduction was observed upon boiling. HWSP content increased, whereas HXSP and HCLSP contents decreased. Heat treatment increased the NDF, ADF and cellulose contents, and most changes were due to changes in cellulose content. The values of hemicellulose and lignin showed irregular pattern upon heating. Contents of total dietary fiber (TDF) were 1.20~7.11% on fresh weight basis. Garlic, edible burdock and pepper leaf showed higher contents of TDF than other vegetables. It was found that a great portion of TDF was composed of insoluble dietary fiber.

• Journal of Food Hygiene and Safety
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• v.23 no.2
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• pp.142-148
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• 2008

We conducted this analysis to make consumers have useful information about consumed foods on the market by investigating the additives contained in food. Korean food additive code (2007) allowed 634 kinds of food additives to be used in domestic products. The food additives consisted of 426 kinds of synthetic additives, 201 kinds of natural additives and 7 kinds of mixture additives. We purchased total 117 kinds of samples; 94 items including sorts of nuts, vegetables and dried fishery products from local markets and discount marts, and 23 kinds of traditional liquors from March to November, 2007, and we researched for various food additives like artificial sweetener, tar pigments and sulfur dioxide. We detected 11.5 to 4,452.3 mg/kg of sulfur dioxide in 18 out of 94 samples except liquors, finding out some artificial sweetener of sodium saccharin in 2 out of 23 liquors, however, no tar pigments were detected from all of the samples. We found out that 2 cases of shredded jujube from china (2476.6 and 4,452.3 mg/kg) proved to exceed regulatory guidance (2000 mg/kg) in sulfur dioxide. Also, we found out that one dried cherry tomato from china contained 88.9 mg/kg and one domestic dried pumpkin 1653.7 mg/kg of sulfur dioxide which should not be detected in vegetables. In traditional liquors, 2 items out of all samples contained 0.4 and 11.1 mg/kg of sodium saccharin which is strictly prohibited to use in liquors.

• Korean Journal of Organic Agriculture
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• v.20 no.4
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• pp.715-725
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• 2012

This study was performed to make the method of food waste manufacturing for feeding to earthworm and different ratio of earthworm cast was investigated for applying vegetable plants that cultivated in a family or roof garden. We made conventional treatment of gardening soil and prepared soils with earthworm cast (the only fertilizer) at 30, 50, 70 and 100% for planting vegetable plants and then we studied its growth feature. The treatment was repeated three times with 12 weeks for each time. The cultivation of radish and chinese cabbage were managed at the same cultivation level for RDA standard cultivation method, and each sample of soils and plants was analyzed by appropriate analysis method. The growth investigation was performed 12 week after planting, and as for growth characteristics, height, leaf diameter, leaf number, leaf length, fresh weight and dry weight were investigated. The chemical characteristics, soils and plants, were surveyed. As for the growth characteristics investigated, radish and chinese cabbage showed the biggest growth in 70% and 50% treatment with average growth of all characteristics, height, leaf diameter, leaf number, leaf length, fresh weight and dry weight, respectively. Applying these results, a new equation for vermicast recommendation for radish and Chinese cabbage in summer (June-August) was presented. The earthworm cast 50% level with the gardening soil showed the high production in chinese cabbage. In case of radish, earthworm cast 70% with gardening soil level showed great growth, significantly.

• Journal of Food Hygiene and Safety
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• v.28 no.3
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• pp.258-266
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• 2013

This study was conducted to determine the PSL and TL properties of foods irradiated with electron beam and gamma-ray. 5 kinds of food including cereal, pulse, fish powder, dried vegetable and tea were irradiated at 0 to 10 kGy by electron beam accelerator or $^{60}Co$ gamma-ray irradiator. The PSL analysis showed negative results for most of the non-irradiated samples. Non-irradiated shrimp powder showed intermediate result. Irradiated samples gave negative or intermediate or positive value which presented the limitation of PSL technique. In TL analysis, there were TL glow curves at around $300^{\circ}C$ with low intensity on non-irradiated samples. Maximum peak in the range of $150-250^{\circ}C$ was appeared on irradiated samples. TL ratio obtained by re-irradiation with 1 kGy was less than 0.1 on non-irradiated samples and higher than 0.1 on irradiated samples. Therefore, in PSL measurement, electron-beam irradiated samples could obtain more clear results. TL analysis showed obvious difference between non-irradiated and irradiated samples. But the identification was impossible for the sample of rice and lemon tea. Because of it's low contents of mineral.

• Korean Journal of Food Science and Technology
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• v.33 no.5
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• pp.641-644
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• 2001

This study was performed for development of new analytical method of monascus pigments in foods. In this method, analysis of monascus pigment in foods has been carried out by detection of monascin and ankaflavin of the main color component of monascus pigment as indicator compounds. Monascin and ankaflavin were isolated and identified by TLC, HPLC, Prep. HPLC, $^{1}H-NMR$ and Mass spectrophotometer. The analysis of monascin and ankaflavin in foods such as massal, sausage, mixed press ham, mixed fish sausage, semi-dried sausage and syrup was performed by using reverse phase high performance liquid chromatograph with Capcell Pak C18 column at wave length 390 nm. The quantitative results of monascin were as follows : $0.01{\sim}3.31\;{\mu}g/g$ item in massal, $0.05{\sim}0.10\;{\mu}g/g$ in mixed fish sausage, and $0.34{\sim}0.35\;{\mu}g/g$ in semi-dried sausage. But the quantitative results of ankaflavin were as follows: $0.02{\sim}0.89\;{\mu}g/g$ in massal, ankaflavin were not founded in other samples.

• Journal of Radiation Protection and Research
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• v.36 no.4
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• pp.209-215
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• 2011

In order to investigate the soil-to-plant transfer factor (TF) of $^{99}Tc$ for Korean major upland crops (soybean, radish and Chinese cabbage), pot experiments were performed in a greenhouse. Soils were collected from four upland fields (two for soybean and two for radish and Chinese cabbage) around Gyeongju radioactive-waste disposal site. Three to four weeks before sowing, dried soils were mixed with a $^{99}Tc$ solution and the mixtures were put into pots and irrigated. TF values were expressed as the ratios of the $^{99}Tc$ concentrations in plants (Bq $kg^{-1}$-dry or fresh) to those in soils (Bq $kg^{-1}$-dry). There was no great difference in the TF value between soils. The TF values for soybean seeds were extremely lower than those for the straws, indicating a very low mobility of $^{99}Tc$ to seeds. As representative TF values of $^{99}Tc$, $1.8{\times}10^{-1}$, $1.2{\times}10^1$, $3.2{\times}10^2$ and $1.3{\times}10^2$ (for dry plants), arithmetic means for two soils, were proposed for soybean seeds, radish roots, radish leaves and Chinese cabbage leaves, respectively. In the case of the vegetables, proposals for fresh plants were also made. The proposed values are not sufficiently representative so successive updates are needed.

• Korean Journal of Food Science and Technology
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• v.32 no.3
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• pp.544-549
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• 2000

This study was performed to compare optimum analytical method for the contents of naturally occurring sulfur dioxide in foods and to investigate the contents of sulfur dioxide in foods in order to provide a fundamental data when distinguish between added and naturally occurring sulfur dioxide. The determination of the contents of sulfur dioxide in foods from the 20 kinds, 180 cases of samples has been analyzed by the optimized Monier-Williams method, modified Rankine method and Acid Distillation/Ion Chromatography. As a result of the study, the contents of naturally occurring sulfur dioxide in foods by the optimized Monier-Williams method showed from 1.02 to 43.87 ppm and highly content of 43.87, 15.37, 11.50, 11.21 and 10.60ppm were observed in garlic, platicodon, green onion, cabbage and onion, the others were less than 10.00ppm. The sulfur dioxide contents in green onion and garlic by modified Rankine method were showed to be 2.87 and 6.14ppm, respectively, the others were detected less than 2.50ppm. The contents of sulfur dioxide by Acid Distillation/Ion Chromatography showed 15.43, 9.82, 5.74, 5.37, 2.14 and 0.49ppm in garlic, cabbage, green onion, onion, potato and apple, respectively and the others were not detected. And the contents of sulfur dioxide in green onion, onion, cabbage and garlic showed higher levels of sulfur dioxide in these foods than the others because of the naturally occurring sulfur containing compounds. The optimized Monier-Williams method, which is the of official analytical method of Korean Food Code, was suitable for monitoring of sulfur dioxide of most foods. Acid Distillation/Ion Chromatography was thought to be adequate for sulfur containing foods such as green onion, onion and cabbage. In order to distinguish between added and naturally occurring sulfur dioxide, it is though to be need of the fundamental data for the contents of sulfur dioxide in sulfite-free foods and continue the investigation for it.