• Journal of the Korean Society of Food Science and Nutrition
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• v.36 no.5
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• pp.622-628
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• 2007

Most fresh-cut agri-food products are less stable than unprocessed materials from which they are made. The objective of this study was the development of a quality control system for fresh-cut agri-food products. In this study, vitamin C, minerals, residual heavy metals, and pesticides of various fresh-cut agri-food products were analysed. Sensory evaluation revealed that overall acceptability scores were less than expected in most products since fresh-cut products are likely to cause browning and easily lose their freshness. Therefore, the postharvest technologies that can maintain the quality, freshness and appearance must be supplied. Although vitamin C and minerals are main nutrients that can be supplied from salads, the results showed that vitamin C and mineral contents were very small and extremely small compared with the values from the food composition tables. It is possible that vitamin C and most minerals that are easily destroyed were lost through minimal processes like peeling and cutting. In safety side, the remaining heavy metal contents of fresh-cut agri-food were investigated and the results showed that copper and lead existed in some products because only cadmium in agricultural produce is controlled by the minimum standard of heavy metal contents in Korea. No residual pesticides were detected in all products.

• Korean Journal of Food Science and Technology
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• v.43 no.2
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• pp.161-168
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• 2011

The purpose of this study was to evaluate microbiological contamination of fresh vegetables in Korea. Twenty types of vegetables were tested for total aerobic bacteria, coliforms, Escherichia coli, yeast and mold, and pathogenic bacteria such as Staphylococcus aureus, Listeria monocytogenes, Bacillus cereus, Salmonella, E. coli O157:H7, Cronobacter sakazakii, Shigella, and Campylobacter. Levels of total aerobic bacteria and coliform on 20 vegetables were between 3.74 and 8.04 log CFU/g, and 0.16 and 5.02 log CFU/g, respectively. The highest contamination levels of total aerobic bacteria were observed on water dropwort, sprouts, mungbean sprout, and ballflower root. There was no significant difference (p>0.05) in microbial contamination levels of total aerobic count, coliform, E. coli, yeast and mold between organic and nonorganic vegetables. When isolation methods using selective agars were applied, L. monocytogenes, B. cereus, Salmonella and Campylobacter were isolated from some fresh vegetable samples. Results of API kit tests showed that L. monocytogenes was identified on Chinese cabbage, cucumber, soybean sprouts, and iceberg lettuce while Salmonella was identified on Korean leek. Furthermore, Campylobacter jejuni was also identified in more than 50 of the 100 samples. However, when positive samples from API kit were tested for real-time PCR or 16S rRNA sequencing method, only B. cereus from perilla leaf, carrot, water dropwort, and sprouts showed positive results. These results indicate that selective agar and API kit detection methods might result in false positive results for some pathogens. Therefore, studies need to improve isolation or confirmation methods for such pathogens.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.15 no.2
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• pp.147-153
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• 1982

Nitrate and nitrite, which readily produce N-nitrosamines by reaction with secondary amines, are widely distributed in natural products such as vegetables and cereals, and are also used as a color fixation in meat products or fish roes. This experiment was carried out to determine the contents of nitrate and nitrite in foods such as fermented sea foods and fresh vegetables purchased at markets in Korea. The contents of nitrate were $0.74\sim13.81\;ppm$ for fermented sea foods and $4.0\sim1,572.5\;ppm$for fresh vegetables. As for vegetables, the nitrate levels of edible herbs were relatively higher than those of greens, fruits and rootcrops. The nitrite contents in fermented demoisells(Chromis notatus), fermented shrimp, fermented small squid, fermented anchovy and salted Alaska pollack roe were very little, while those in fermented hairtail and fermented entrails were not detected. As for vegetables, nitrite levels found for cabbage and lettuce were relatively as high as 3.8 ppm and $2.5\sim2.9\;ppm$, respectively, but were not detected in Korean cabbage, green perilla leaf, pepper, garlic and burdock. Of vegetables, the nitrate values in the outer part of Korean cabbage, stems of water cress and leaves of green onion were higher than in the other parts. Little variety of the nitrate levels were found during 4 days storage. In the comparison of low temperature storage and room temperature storage, lettuce, pumpkin and spinach contained higher levels of nitrate at low temperature storage, while eggplant and green onion, at room temperature storage.

• Journal of Bio-Environment Control
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• v.16 no.4
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• pp.420-425
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• 2007

This study was conducted to find out the effect of vitamin C treatments on the storability of several baby vegetables; endive, green romaine lettuce, pak-choi, red romaine, lollo rosa, and ssamchoo. The vitamin C was treated by the foliar spray which was carried out 3 times before harvest or dipping in vitamin C solution for 5 minutes after harvest. The vitamin C contents of 6 different baby vegetables were higher in vitamin C treatments than control, whereas the difference of vitamin C content between treatments was disappeared after storage. The fresh weight of ssamchoo and lollo rosa lettuce treated by vitamin C was maintained higher than that of control. There was not significant difference in visual quality among treatments, though some of baby vegetables treated by washing with vitamin C showed better visual quality than the others. The contents of carbon dioxide, oxygen and ethylene in MAP with baby vegetables did not show any difference among treatments. As the result, high concentrated vitamin C treatment, such as the foliar spray and washing (dipping) had a role of increasing functionality, but the enhanced functionality, high vitamin C, did not affect storability in baby vegetables.

• Korean Journal of Community Nutrition
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• v.11 no.5
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• pp.661-672
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• 2006

This study was performed to determine the dietary risk factors associated with hypertension. The hypertensive group were composed of 112 hypertensive patients (male 53, female 59) who first visited the hypertension clinic and had been diagnosed as having primary hypertension ($SBP{\ge}140mmHg\;or\;DBP{\ge}90mmHg$). The regular visitors or the subjects on special diets or medical therapies were excluded. The normal group consisted of as subjects (male 41, female 54) matched with age and socioeconomic levels. The subjects having higher intakes (above the 75 percentile) in energy, protein, iron, vitamin A or C showed significantly higher hypertension risk estimated with odds ratio after the covariance factors (age, sex and BMI) were adjusted. More than 2400 mg of sodium (6 g of salt) intake was associated with significantly higher risk of hypertension (odds ratio: 1.773, CI: 1.014-3.014 for $SBP{\ge}140mmHg$; odds ratio: 2.373, CI: 1.359-4.215 for $DBP{\ge}90mmHg$). Hypertensive group showed significantly increased intakes of vegetables and fish and shell fish compared to the normal group. When the vegetable intakes were classified into Kimchi, fresh vegetables and cooked vegetables with seasoning, the hypertensive group was observed as having higher intakes of Kimchi and cooked vegetables with seasoning. The intakes of highest quartile for vegetables (${\ge}327g/day$) (odds ratio: 3.164, CI: 1.740-5.752), fish and their products (${\ge}102g/day$) (odds ratio: 2.756, CI: 1.486-5.109), grains(${\ge}311g/day$) (odds ratio 2.393, CI: 1.186-4.832), meats and their product (${\ge}106g$) (odds ratio: 2.210, CI: 1.225 - 3.987) compared to the lower were significantly associated with the higher risk of hypertension estimated with DBP (${\ge}90mmHg$) after covariance factors were adjusted. In conclusion, our findings confirm that higher intake of energy or sodium are associated with the increased risk of hypertension. Because increased intake of vegetable or fish was associated with the higher risk of hypertension, in contrast with the finding of western countries, choosing or preparation of vegetables or fish with reduced salt is recommended.

• Food Science and Preservation
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• v.19 no.1
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• pp.62-66
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• 2012

With the rapid growth of fresh-cut produce market, the South Korean fresh-cut industry is facing the challenge of ensuring food safety. As the estimation of the microbial numbers in fresh-cut produce processing lines (tools, and equipment) using the conventional microbiological techniques takes days, so there is a need for faster and easier monitoring methods. This study was conducted to investigate the use of ATP bioluminescence assay to measure the degree of microbial contamination from three actual fresh-cut processing lines. The samples collected from frech-cut vegetables, and fresh-cut fruits processing plants were tested for the estimation of the bacterial number, using the ATP bioluminescence and microbiological methods. The result of former was transferred to log RLU/100 $cm^2$, and that of the latter was transferred to log CFU/100 $cm^2$. A positive linear correlation between the ATP bioluminescence assay value and aerobic-plate count was found for fresh-cut processing lines, with a correlation coefficient of 0.8772 (n=50). The results of this study indicate that ATP bioluminescence assay can be used to monitor microbial contamination in fresh-cut produce processing plants, and can help improve the hygiene therein.

• Korean journal of food and cookery science
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• v.13 no.4
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• pp.422-426
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• 1997

Fresh broccoli is known to have the highest content of sulforaphane (S-methylsulfinylbutyl isothiocyanate) among all vegetables. Since isothiocyanates are formed from myrosinase-catalyzed hydrolysis of glucosinolates during tissue destruction of broccoli, the formation of sulforaphane in the extract of broccoli was examined under various processing conditions. The amount of sulforaphane in processed broccoli was measured using GC/MS analysis. Among fresh, dried, and boiled broccoli fresh broccoli exhibited the highest content of sulforaphane. Sulforaphane was maximally produced from the homogenate in 0.1 M phosphate buffer containing 1 mM Vitamin C stored at room temperature for 1 hr. In boiled broccoli, the amount of sulforaphane decreased as the boiling time increased, and reached to 10% of control after 30 min boiling. The amount of sulforaphane was decreased remarkably in dried broccoli in which freeze-dried and heat-dried broccoli had about 50% and 30％ of fresh ones, respectively.

• Food Science and Preservation
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• v.19 no.1
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• pp.54-61
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• 2012

According to lifestyle changes, the consumers' concern about food also shifts from calories and nutrition to health and convenience. Fresh-cut produce is one of the new turns in the consumption pattern of fruits and vegetables. The increasing demand for it requires processors to make them stable in quality and safe from microorganisms. The results of the evaluation of the production process and hygienic management of fresh-cut lettuce revealed that the facilities used, such as the drainage holes, floors, and door knobs, were severely contaminated with microbes, and that the work equipment, workbenches, landing nets, and centrifuges were highly contaminated. Accordingly, improved production processes and management systems are necessary, as is the implementation of a quality control system from the stage of raw-material purchase to the distribution stage.

• Food Science and Preservation
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• v.5 no.1
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• pp.23-28
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• 1998

The objective of this study was to investigate the methods of quality maintenance using modified atmosphere packaging with various quality preservatives at ambient and low temperatures. Ethylene(<1.0ppm) accumulated during modified atmosphere storage of Chinese cabbage using polyethylene film(60$\mu\textrm{m}$) caused quality deterioration such as yellowing and abscission. The addition of potassium permanganate reduced ethylene level and thus extended storage life of l00% at 20$^{\circ}C$ and 140% at 0$^{\circ}C$. To establish the storage conditions of minimally processed sit and vegetables, the experiment was conducted with various quality preservatives and packaging materials. Ceramic film(Zeolite 7%, 60$\mu\textrm{m}$) showed increasing storage life of 50%, reducing total microbial counts of 50% and keeping high appearance quality of minimally processed pears stored at 20$^{\circ}C$ and 0$^{\circ}C$. Minimally processed Chinese cabbage treated with l% CaCl2 at 20$^{\circ}C$, and 1% CaCl2 and 1% NaCl at 0$^{\circ}C$ has a longer storage life of 90% with good maketable quality. Treatment of 1% NaCl for cut Asian penis appeared increased storage life of 100%, decreased cut surface browning and the best overall acceptability by a sensory panel.

• Research in Plant Disease
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• v.17 no.2
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• pp.232-234
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• 2011

During survey of postharvest diseases of vegetables in the middle region of Korea in 2003, 2004 and 2005, new disease symptoms showing watery rot and soft rot were observed. In this study, the disease causal agents were identified as Geotrichum candidum, and their host range and pathogenicity were investigated. G. candidum isolated had wide host range and strong pathogenicity against carrot, cucumber, tomato and pumpkin. The disease occurrence on several vegetables that G. candidum can be a serious threat to stable production of fresh vegetable.