• Journal of the Korean Chemical Society
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• v.61 no.5
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• pp.244-250
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• 2017

Reduction of (${\pm}$)-3-ketoproline ethyl ester (1) by $NaBH_4$ in the presence of $CaCl_2$ and $MgCl_2$ as the chelating agents gave selective products cis-3(R/S)-alcohols, while reduction by $NaBH_4$ alone or chelated with $NiCl_2$ and $AlBr_3$ gave mixtures of cis- and trans-alcohols. The reduction of (${\pm}$)-1 by various vegetables however, gave exclusively the cis-alcohol as the major and trans-alcohol as the minor. On the contrary, reduction of (${\pm}$)-1 by carrot afforded a mixture of cis- and trans-alcohols, in which the trans-alcohol exists as the major product. In addition, we found that this biocatalyst selectively converted S-enantiomer of (${\pm}$)-1 to the cis-alcohol, and R-enantiomer to a mixture of cis- and trans-alcohols with cis-alcohol as the major product. This fact prompted us to use various fresh plant tissues for stereoselective reduction of diverse types of pyrrolidinones, as its stereoselectivity towards racemic mixtures is higher compared to that using chemical reducing agents.

• Journal of the Korean Society of Food Science and Nutrition
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• v.28 no.5
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• pp.1082-1086
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• 1999

Dried vegetables, white ginseng and spices, which were exposed to gamma and electron beam irradiation, were used in a detection study by measuring their starch content and viscosity change. The samples tested showed different levels of starch content(15.64~60.86%), which was not directly proportional to the viscosity of the samples. The correlation coefficients between irradiation dose and viscosity change were lower in the samples, such as cabbage, carrot, clean vegetable(chunggyungchae), garlic, mushroom, green onion, and red pepper, while some higher coefficients were found in ginger(R2=0.9271), white ginseng (R2=0.6223) and onion (R2=0.7909). Thus, dried ginger and white ginseng were selected to be used for a detection of irradiated samples using specific parameters(threshold values). Specific parameter for the nonirradiated ginger and ginseng were 13.31 and 13.93, respectively. On the other hand, gamma and electron beam irradiated samples at 2.5 kGy, the lowest dose for a commercial purpose, showed decreased values, 11.92 and 11.15 in ginger, and moreover 4.40 and 5.10 in ginseng. It is expected that a proportional decrease in a specific parameter with the absorbed doses will be a potentially useful index for detecting whether starchy foods have been irradiated or not.

• Journal of Food Hygiene and Safety
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• v.1 no.1
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• pp.31-38
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• 1986

In order to investigate the harmful trace elements in Korean common vegetable, the contents of Lead, Cadmium, Copper, Zinc and Manganese are studied in this paper. As shown in the Table 1, the following vegetable samples collected from the agriculture-marine products market I Seoul were used; root vegetables-potato, sweet potato, carrot, radish, onion and garlic, fruit vegetables-cucumber, pumpkin, green pepper, egg plant, tomato and melon. The contents of the harmful trace elements were determinded by means of atomic absorption spectrophotometry. These elements were extracted from the vegetables with the DDTC-MIBK extraction method. The results were as follows; 1. The average contents of the harmful trace elements in the vegetables were as follows; Root vegetables-Lead, 0.387 ppm; Cadmium, 0.030 ppm; Copper, 1.267 ppm; Zinc, 7.395 ppm; Manganese, 5.380 ppm. Fruit vegetables-Lead, 0.259 ppm; Cadmium, 0.028 ppm; Copper, 1.155 ppm; Zinc, 3.732 ppm; Manganese, 3.532 ppm. 2. The contents of harmful trace elements in vegetables were significantly low compared with foreign standards. This means that vegetables contamination with those harmful trace elements is not significant at present.

• The Korean Journal of Pesticide Science
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• v.8 no.4
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• pp.280-287
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• 2004

We investigated the residual amounts of endosulfan and procymidone taken by vegetables grown in hydroponics culture and field conditions treated with the pesticides in order to evaluate safe cultivation concentration of the pesticides in the vegetables. Endosulfan and procymidone were selected as test pesticides because they have been reported to frequently detect in agricultural products at different concentrations. In hydroponic culture, by Chinese cabbage, procymidone was absorbed 3.8 times higher than endosulfan. The higher the pesticide concentration get, the worse the plant grew. In soil treated with 10 mg/kg of endosulfan, the pesticide absorbed by Leafy radish, Chinese cabbage and radish was less then their MRLs. In case of carlot, the residue level in soil which did not exceed its MRL was 1 mg/kg. The concentrations of procymidone in soil which did not exceed the MRLs in Leafy radish, Chinese cabbage, radish and carrot were 10, 10, 2 and 1 mg/kg, respectively Usually aged endosulfan and procymidone residues were less absorbed into crops than the fresh ones. Chinese cabbage absorbed more endosulfan and pocymidone than leafy radish, radish doing more than carrot.

• Food Engineering Progress
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• v.22 no.4
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• pp.309-314
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• 2018

In recent years, interest in halal authentication from the domestic food and cosmetics field has been growing for advances into the overseas halal market. For halal authentication, the product must not contain haram ingredients derived from pig, dog, human, GMO, etc. In this study, the presence of haram ingredients in plant extracts (carrot, oyster mushroom, and pine needle) treated with papain and bromelain and cosmetics (mask pack and cream) containing these extracts were analyzed by PCR to confirm whether these cosmetics were suitable for halal authentication. Detection limits of the PCR method that specifically detected template DNA of human, pig, dog, and GMO were $1.29{\times}10^3$, $1.14{\times}10^3$, $1.24{\times}10^2$ and $2.02{\times}10^3copies/tube$, respectively. PCR was not inhibited by the plant extracts or cosmetic ingredients. Results of PCR for the plant extracts or cosmetics containing these extracts were all negative. This PCR method could be used to rapidly identify the presence of haram ingredients in raw materials or final products during the manufacturing process of food and cosmetics.

• Korean Journal of Food Science and Technology
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• v.32 no.3
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• pp.525-530
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• 2000

A study was carried out to establish the detection method of irradiated agricultural products cultivated in Korea by Thermoluminscece(TL). Samples were irradiated using Co-60 gamma rays at various doses(0.05, 0.1, 0.2, 0.3 and 0.5 kGy). After irradiation, separated minerals of the samples measured by TL. TL intensity increased with increasing doses and the irradiated samples were higher than the non-irradiated samples. TL first and second glow curves showed maximum TL temperature point at $176.16{\sim}190.08^{\circ}C$ and $143.84{\sim}146.56^{\circ}C$, respectively. All the irradiated samples can be classified correctly by the shape of the glow curve and the glow curve ratio. Correlation coefficients of ginger, carrot, potato and sweet potato were 0.9968, 0.8522, 0.9612 and 0.9071, respectively, that showed very high correlation between irradiation dose and TL intensity. Therefore, these results suggest that TL measurement is an useful detection method for irradiated agricultural products.

• Korean Journal of Food Science and Technology
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• v.53 no.4
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• pp.470-478
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• 2021

This study was conducted to monitor residual pesticides in a total of 527 school foodservice agricultural products from 2019 to 2020 in Incheon. Pesticide residues in the samples were analyzed by the multi-residue method in the Korean food code for 373 pesticides using GC-MS/MS, LC-MS/MS, GC-ECD, GC-NPD, and HPLC-UVD. By monitoring the pesticides, 12 (2.3%) of the 527 pesticides were detected, and 2 (0.4%) samples exceeded the maximum residue limit. Twelve types of pesticides were detected in the agricultural products of carrot, chard, chili pepper, chwinamul, crown daisy, parsley, perilla leaves, and spinach. As a means of risk assessment through the consumption of agricultural products detected with pesticide residues, the proportion of estimated daily intake to acceptable daily intake was estimated in the range of 0.0000-39.7425%. Results showed no particular health risk through the consumption of school foodservice agricultural products with pesticide residues.

• Journal of The Korean Society of Grassland and Forage Science
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• v.37 no.4
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• pp.290-300
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• 2017

In vitro fermentation was conducted to figure out alternative fiber sources for horse feed. For the development of value-added products as a horse feed resource, the pomaces from apple, carrot, grape, and citrus were fermented under solid-state conditions in the presence of 60% soybean meal with 40% of each fruit pomace at 60% of moisture content. Lactobacillus plantarum SK3873, Lactobacillus plantarum SK3893, Weissella cibaria SK3880, and Bacillus subtilis SK3889 were isolated from the fermented fruit pomace by inoculation of horse feces. For the growth of Bacillus subtilis, Saccharomyces cerevisiae, and Lactobacillus plantarum, they were inoculated in 3-step order at 0, 12, and 24 h, respectively. The fruit pomace was fermented for 48 h at $35^{\circ}C$. The pH of the apple, carrot, grape, citrus and all mixed pomaces decreased from 5.45~6.25 to 4.40~4.77. Microbial growth was maintained at $10^8{\sim}10^9cfu/g$. After 12 and 24 h incubation, dry matter of carrot pomace were highest at 54.84 and 56.66%, respectively (P<0.05) and that of grape pomace was lower than others during fermentation (P<0.05). Dry matter was generally reduced by about 20%. NDF decreased gradually or maintained after 24 h, indicating the fiber degradation. Ash content tended to decrease during fermentation. After 48 hours fermentation, Bacillus, yeast and Lactobacillus showed an excellent growth by using juice by-products. These results suggest that fermented juice pomace has a potential as horse feedstuff with probiotics to maintain beneficial microflora in horse gut.

• Food Science and Preservation
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• v.9 no.1
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• pp.46-50
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• 2002

This study was carried out for dietary safety based on the level of pesticide residues in 17 kinds of the agricultural products (apple, cabbage, cabbage kor, carrot, cucumber, pepper, onion, potato, radish, spring onion, pumpkin, lettuce, garlic, drapwort, spinach, leek crown daisy) consumed in Kyunggi-do and Inchon-city that provided for the army. From January 1998 to December 2001, ten organochlorine pesticides in 1075 samples were analyzed by using GC-ECD. According to the results, one kind of pesticides was detected in 135(12.5%) samples, and two kinds were in 7 (5.18%). While dicofol and tetradifon was not fecund. Detection rate of pesticides were 9.02% for $\alpha$, $\beta$-endosulfan, 2.8% far chlorothalonil, 0.46% for γ-BHC, 0.40% for chlorobenzilate, 0.33% for folpet, 0.28% far DDT, 0.15% for captafol, and 0.11% for captan. Dectection ranges of pesticides were from 0.001 to 0.092 ppm for $\alpha$, $\beta$-endosulfan, from 0.003 to 0.023 ppm for chlorothalonil, from 0.003 to 0.006 ppm far γ -BHC, from 0.001 to 0.003 ppm for DDT, from 0.009 to 0.095 ppm for folpet, 0.05 ppm for captan, 0.01 ppm for captafol, and 0.008 ppm far chlorobenzilatel respectively. Consequentlyl all detected pesticide levels in samples were below maximum residue limits(MRLs) in Korea and Codex.

• Magazine of the Korean Society of Agricultural Engineers
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• v.17 no.1
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• pp.3677-3684
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• 1975

A newly devised dryer with heated air for the farm products, especially suited for high water content materials such as red pepper, Beer ground, each Vegetables, and Low water content materials such as Rough rice was tested for its thermal efficiency and drying mechanism, and the optimum conditions for each sample were established. In order to improve the present rural situation of drying farm products which entirely dependent upon natural solar radiation, a study upon an economic multi-parpose dryer was conducted. A series of drying tests were run first with red pepper which is one of the important cash crop in Korean farm. And successive series of tests were also run with such proaucts as garlic, sweet potatoes, green onion, radish, Beer ground and Rough rice. The results from the above experiment in drying system with heat dryer can be summarized as follows. 1. Drying duration could be shortened by the tempering effect in high water content crop such as red pepper and beer ground. 2. The color changes occured in around 20% water content in red pepper. The degree of color change was heavily affected by high temperature and short drying duration. 3. The drying condition of red pepper was most favourable at the temperature of 85$^{\circ}C$ in early stage and 80$^{\circ}C$ in middle stage and 75$^{\circ}C$ at the final stage, and with the air rate of 0.81㎥/sec and with sample amount of 200kg. 4. The drying condition of Rough rice(I.R.667) was most favourable at the templature of 40$^{\circ}C$ in early stage and 35$^{\circ}C$ in middle stage and final stage and with the air rate of 0.2㎥/sec and with sample amount of 75kg. 5. In order to prevent the color change of red pepper and to assure high efficiency in drying mechanism, it was necessary to lower the temperature as the time passes in drying process. 6. For vege tables, the drying rate were short in early stage and there was also tempering effect. However, for garlics, Constant drying rates through the early and final stages were observed and there were no tempering effects. 7. The drying condition or capability were as follows; Sample drying temp($^{\circ}C$) amount of material(kg) drying time(hr) Red pepper 85 200 9 Garlic 85 150 7 Sweet potato 85 200 6 Green Onion 85 200 4 Carrot 85 200 4 Radish 90 250 4 Rough rice(I.R.667) 35 75 4 Beer ground 90 320 3 Considering the above result of experiments, if this kind of dryers were distributed Korean farm and the optimun process were practiced in rural area, it would certainly help them improving the qualites of their product preventing their undue losses, and thus assuring an increase of Korean farm income and promotion of their living standards.