• Korean Journal of Fisheries and Aquatic Sciences
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• v.12 no.4
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• pp.261-266
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• 1979

This experiment was carried out to evaluate the sanitary quality of cultured vegetables and to check the removing rate of bacteria by treating methods such as washing with tap water or commercial detergent, or blanching. Samples collected from farm land located at Busan suburbs and markets were Fragaria chiloensis var. ananasa, Lycopersicum esculentum, Capsium longum, Cucumis sativus, Lactuca scariola var. sativa leaf of Perilla frutescens var, japonica, Oananthe stolonifera and Allium odoium. Fecal coliform MPN was ra god from less than 30 to 430,000 per 100 grams of samples examined while plate count was $7.2\times10^3\;to\;2.2\times10^7$ per gram. Usually contamination rate of fecal coliform of leaf vegetal)les was much higher than that of fruit vegetables. Removing rate of bacterial density of vegetables by washing three times with tap water was about $70\%$ in fruit vegetables, about $20\%$ in leaf vegetables but it was about $80\%$ in leaf vegetables by washing with a commercial detergent. Sirvival rate of viable cell count of leaf vegetables was less than $0.1\%$ after blanching for one minutes in boiling tap water, Composition of coliform was $18\%$ Escherichia coli group, $22\%$ Citrobacter freundii group and $60\%$ Klebsiella aerogenes group, among Escherichia coli, type I being $16\%$ in total. The coliform detection from BGLB gas positive tubes being planted with various vegetables was about $80\%$ in the result of IMViC reaction.

• Korean Journal of Organic Agriculture
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• v.6 no.1
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• pp.63-75
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• 1997

This study aims to find out the devices to minimize the amount of nitrate ingested from kimchi, the main way of vegetable intake for Koreans, and the basic data to deliver to calculate the total daily intake for Korean, investigating the year-round changes of nitrate content in vegetables for Kimche raw material, and changes of nitrate content by salting of chinese cabbage, and stewed kimchi through the use of different cooking methods. The results obtained were summarized as follow: over between 205-6655mg/kg f.w. in chinese cabbage, 480-3970mg/kg f.w. in chinese radish, 157-5820mg/kg f.w. in lettuce and 29-520mg/kg f.w. in cucumber respectively. Therefore it was strongly adviced to introduce the nitrate limit value of vegetables in Korea if the nitrate content in Kimchi should be reduced to meet the nitrate ADI(Acceptable Daily Intake, 219mg60kg b.w) of FAO.WHO, because the nitrate content in Kimchi reflects the nitrate content in vegetables. In order to keep the low nitrate content in Kimchi. it was adviced to remove the outer leaf which contains 2-3 times higher nitrate content compare to the inner leaf at the time of preparation, i.e. chinese cabbage, before the soaking treatment in salt solution for Kimchi making process. The dehydration by soaking treatment in salt solution occurred at 0.9%~4.7% in leaf midrib and more than 13%~24% in leaf blade. The nitrate content after soaking in salt solution was increased 107%~123% compared with before soaking, increasing rates of nitrate content in the outer and inner leaf midrib were higher than those in leaf blade. The increase of nitrate content in salt solution after soaking due to the dehydration of chinese cabbage by soaking treatment. The Kimchi stew(Kimchi JJige) was processed with and without animal oil, but the amount of nitrate in kimchi stew did not decrease both treatments, but it increased after the processing since the water in Kimchi stew has got low by boiling.

• Food Science and Preservation
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• v.16 no.5
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• pp.699-704
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• 2009

Commercially produced 'baby leaves' of Brassica campestris var. narinosa (Chinese cabbage) were used in the present study. Baby leaf vegetables were sown on 128 cell plug trays and harvested 30 days after sowing. For mechanical stress experiments, seedlings were thinned to three per cell, selected for uniformity, and watered at the base. Trays were treated with mechanical stress by stroking back and forth 50 times, using a sheet of A4 paper folded to double thickness. Plants were treated between 12:00 and 14:00 daily for 15-20 days. Harvested baby leaf vegetables were packed in MAP salad bags made of P-plus film, $50{\mu}m$ polypropylene (PP) film, and polyethylene terephthalate (PET) boxes. Fresh weight was well-maintained under P-plus and PP film on storage at $8^{\circ}C$. However, loss of fresh weight occurred quickly in PET boxes, and vegetable quality deteriorated rapidly. Stressed leaves were smaller but thicker, with an increased dry weight ratio. We thus suggest that P-plus or PP film is most appropriate packing for marketing of baby leaf vegetables, which should be stored at $8^{\circ}C$. Our data on baby leaf vegetables also make a significant new contribution in that we demonstrate a positive effect of stress touching on baby leaf processability.

• Journal of the East Asian Society of Dietary Life
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• v.10 no.1
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• pp.42-47
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• 2000

Flavonoids in commerical green-yellow vegetables (carrot, mugwort, perilla leaf, leek and water dropwort) were analyzed by HPLC. Flavonoids analyzed in samples were myricetin, luteolin , qercetin, apigenin and kaempferol. When 2N HCI and a reaction period of 1 hours was used, quercetin and kaempferol could be detected in leek and water dropwort, luteolin and apigenin could be detected in perilla leaf. Increasing reaction period up to 6 hours with 2N HCI led a degradation of quercetin and kaempferol to approximately 90% in leek and water dropwort, but it led to a increasing of luteolin and apigenin of maximum 300% in perilla leaf. After the blanching process, the amount of the flavonoids increased whereas the components of the flavonoids were not changed.

• Journal of Food Hygiene and Safety
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• v.17 no.2
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• pp.101-105
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• 2002

A total of 53 vegetables and fruits, consisting of 23 leaf vegetables, 4 fruits vegetables, 4 edible roots,7 spice vegetables and 15 fruits were analyzed for contents of nitrate and nitrite by ion chromatography. Nitrite was detected 10 of 23 kinds of leaf vegetables, which was dominant in lettuce by average 349.9 mg/kg. Nitrate contents of leaf vegetables were average 578.3 mg/kg, 415.7 mg/kg, 348.6 mg/kg in wild plant, mustard leaf and chinese vegetable, respectively. Nitrite was not detected in fruits vegetables and rootcrops but the nitrate contents were abundant and the highest in squash(average, 86.2 mg/kg) and radish(average, 297.5 mg/kg), respectively. In spice vegetables, mate contents were from 0 to 29.8 mg/kg, but not detected in garlic. In welsh onion, its nitrite were higher in small type than large type, while nitrate contents were higher 3 times in the latter. Nitrate contents of fruits were lower in apple(average, 0.5 mg/kg) and higher in plum(average, 76.6 mg/kg) than other samples.

• Journal of the East Asian Society of Dietary Life
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• v.7 no.2
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• pp.175-180
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• 1997

Beta-carotene and lutein contents in 7 different green leafy vegetables(perilla leaf, mugwort, chwi, lettuce, spinach, leek, and crown daisy) were analyzed by HPLC. The isocratic separation was performed on a ${\mu}-Bondapak$ $C_{18}$ column with a solvent system of acetonitrile : dichloromethane : methanol = 70:20:10. To check the reliability of the method applied, precision and recovery tests were performed. Perilla leaf showed the highest ${\beta}-carotene$ content(12,570 ${\mu}g$ / 100 g), followed by mugwort and chwi, all of those have ${\le}10,000\{\mu}g\{\beta}-carotene$ per 100 g vegetables. Green lettuce, spinach, leek, crown daisy and reddish brown lettuce contained 9,869, 6,689, 5,664, 3,601 and 3,299 ${\mu}g\{\beta}-carotene/100 g$, respectively, Lutein content was the highest in perilla leaf($13,718{\mu}g/100 g$) followed by chwi($11,989{\mu}g/100 g$), mugwort($11,522{\mu}g/100 g$), green lettuce($10,307{\mu}g/100 g$) and spinach($10,115{\mu}g/100 g$). ${\beta}-carotene$ contents in perilla leaf, mugwort, chwi and green lettuce were 47.8~49.6% of total carotenoids, and ${\beta}-carotene$ contents in the other green leafy vegetables analyzed were 37.7~41.4% Vitamin A contents of green leafy vegetables analyzed by HPLC were 2~6 times higher than the vitamin A values shown in food composition tables except crown daisy.

• Journal of the Korean Society of Food Science and Nutrition
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• v.21 no.2
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• pp.149-153
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• 1992

The antimutagenic effect of green-ye1low vegetables on the mutagenicities induced by N-methyl-N'-nitro-N-nitrosoguanidine(MNNG) and N-nitrosodimethylamine (NDMA) in Salmonella assay system and also their inhibitory effect on AZ-521 human gastric cancer cells were studied. Twenty-four items from twenty six kinds of vegetables(92%) revealed antimutagenic activity toward MNNG (p< 0.0l, 0.05). Perilla leaf, Korean cabbage, cauliflower, lettuce, mustard leaf, water dropwort, small water dropwort, carrot and burdock inhibited the mutagenicity more than 80%. The methanol extracts of the vegetables also showed the antimutagenic activity toward NDMA (p< 0.01, 0.05). Especially, perilla leaf, kale, soybean sprout and onion inhibited more than 80% of the NDMA induced mutagenicity in S. typhimurium TA100. Small water dropwort and perilla leaf exhibited the strong inhibitory effect (97~100%) on the growth of the AZ-521 human gastric cancer cells. Soybean sprout, water dropwort, broccoli, crown daisy, green red pepper, red pepper leaves, spinach, cabbage and sweet potato also inhibited growth of the cancer cells (p < 0.001~0.05).

• Korean journal of food and cookery science
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• v.12 no.1
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• pp.34-39
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• 1996

This study was conducted in order to determine the effect of various cooking methods (boiling, pressure cooking, steaming and microwave heating) on mineral content, color and sensory quality of spinach, chinese cabbage, and cabbage. It was shown that steaming and microwave heating were desirable methods for all three vegetables. Both the acceptability and the retention of mineral content were high when these methods were used. It was also shown that boiling more than 5 min. and pressure cooking were not appropriate for leaf vegetables since both the acceptability and the retention of mineral contents were low in those methods.

• Food Science and Preservation
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• v.19 no.1
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• pp.1-6
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• 2012

The effect of the packing methods for enhancing the shelf life and improving the postharvest quality of the $tah$ $tasai$ Chinese cabbage baby leaf vegetable was studied during storage. Fresh baby leaf vegetables were packed in four commercial packaging types: (1) a non-perforated bag with a 0.03-mm oriented polypropylene (OPP) film; (2) a perforated bag with 1.0-mm-diameter holes on an OPP film; (3) a 0.40-mm polyethylene terephthalate (PET) container with a hinged lid; and (4) an expanded polystyrene (EPS) tray wrapped with a 0.02-mm polyvinyl chloride (PVC) film. The quality parameters, such as the weight loss, moisture content change, color difference, and appearance of the baby leaf vegetables were investigated. The baby leaf vegetables in the PET container and in the non-perforated OPP film bag showed relatively low weight loss, high moisture content, and good external appearance compared to those in the EPS tray and in the perforated OPP film bag during limited storage periods, at $16^{\circ}C$. The PET container also protected the baby leaf vegetables from physical damage. The study results will enable the selection of a better packaging system for extending the freshness and increasing the market ability of baby leaf vegetables.

• Korean journal of food and cookery science
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• v.25 no.5
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• pp.632-642
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• 2009

In this study the microbiological quality of vegetables was evaluated in relation to the sanitization methods used and vegetable types which consisted of raw food ingredients used in foodservice operations. We analyzed the microbial quantities on lettuce and spinach, which were used as leaf vegetables and cucumber and tomato, which were used as fruit vegetables according to various disinfection methods using different chlorine concentration(50 ppm, 100 ppm, 200 ppm) and exposure time(5 min, 10 min) over 5 days. When the effects of the disinfection methods on microbial qualities and sensory evaluation were analyzed, the following results were obtained. First, in the leaf vegetables, disinfection with a chlorine concentration of 200 ppm for a 5 minutes exposure time was needed to control microbial growth. Second, fruit vegetables sterilized with tap water had reduced microbial qualities after an extended amount of time relative to chlorine disinfection, that is, disinfection with a chlorine concentration of 50 ppm for 5 minutes exposure time was desirable.