• Journal of the East Asian Society of Dietary Life
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• v.26 no.3
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• pp.201-206
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• 2016

Consumers are more aware of their health and more conscious of environmental conditions nowadays. As such, there is an increasing demand for agri-foods obtained from organic agricultural practices. The present study aims to compare quality characteristics and antioxidant activities between organically and conventionally grown perilla leaf, leaf lettuce, broccoli, and cabbage. The conventionally grown leafy and stem vegetables showed significantly (p<0.05) higher weights and lengths. There was no significant difference in moisture contents of organically and conventionally grown vegetables. The L (lightness), a (redness), and b (yellowness) values of organically and conventionally grown perilla leaf, leaf lettuce, broccoli, and cabbage showed significant differences (p<0.05). Conventionally grown perilla leaf, leaf lettuce, and broccoli showed significantly (p<0.05) higher DPPH and ABTS radical scavenging activities. Overall, the quality characteristics of conventionally grown leafy and stem vegetables were higher than those of organically grown ones. On the other hand, antioxidant activities of organically grown leafy and stem vegetables were higher than those of conventionally grown ones. Further studies are recommended to evaluate other differences such as flavor, organic acid, polyphenol, vitamin, mineral, and bioactivity compounds between organically and conventionally grown vegetables.

• Journal of Food Hygiene and Safety
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• v.38 no.3
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• pp.164-169
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• 2023

Vegetables are rich sources of dietary fiber, which exhibit various health benefits. In the Republic of Korea, vegetables are consumed after cooking using different methods. However, they are most commonly eaten raw or blanched. In this study, chamnamul, sesame leaf, Fischer's ragwort, burdock root, and garlic stem from Korea were analyzed according to the Korean Food Code, and changes in dietary fiber content after blanching were compared. Blanching reduced the total dietary fiber (TDF) content in chamnamul (from 3.67±0.03 to 2.61±0.14 g/100 g), burdock root (from 4.95±0.40 to 3.89±0.10 g/100 g), and sesame leaf (from 4.32±0.12 to 3.65±0.17 g/100 g), but increased it in Fischer's ragwort (from 6.09±0.49 to 6.43±0.01 g/100 g) and garlic stem (from 4.52±0.35 to 5.09±0.04 g/100 g). Sucrose, glucose, and fructose were detected in the vegetables; however, sesame leaf did not have sucrose. Fresh burdock root had the highest sucrose content (1.71±0.07 g/100 g) whereas garlic stem had the highest glucose and fructose content (1.65±0.02 and 1.73±0.02 g/100 g, respectively) compared with other vegetables. Upon blanching, the free sugar content of vegetables decreased for all sugars except for sucrose, which increased in Fischer's ragwort (from 0.10±0.01 to 0.14±0.01 g/100 g) and garlic stem (from 0.76±0.00 to 0.83±0.01 g/100 g). These results can provide information on blanching-associated changes in the content of dietary fiber and free sugar in foods prepared using these vegetables.

• 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 Biosystems Engineering
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• v.32 no.6
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• pp.395-402
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• 2007

This study was carried out as basic researches to develop the leaf vegetable harvester. This study was conducted to investigate physical and rheological properties of bundled leaf vegetables with stem (Chinese leek, Crown daisy and Chamnamul) as test materials held and picked-up by a machine. Stress-strain behavior, stress relaxation, and strain recovery for the bundled materials were analyzed using simple Maxwell model. Physical and rheological properties of the materials were investigated by measuring rupture load, deformation and stress experimentally. Also, strain recovery time when unloading was measured using super high speed camera. Recorded recovery time for stress-strain behavior was0.026 s for Chinese leek with liner strain recovery, 0.046 s for Crown daisy and 0.05 s for Chamnamul with non-linear strain recovery. Furthermore, the strain recovery time for permanent deformation was 0.026 s, 0.046 s, and 0.05 s for Chinese Leek, Crown daisy and Chamnamul, respectively. Finally, strain recovery time and strain recovery ratio for the test materials were 0.17 s, 60.4% in Chinese leek, 0.12 s, 55.3% in Crown daisy, 0.15 s, 58.7% in Chamnamul. Here strain recovery time means that how fast the test materials are recovered from initial deformation and strain recovery ratio means how much the test materials are recovered from initial deformation. The above results show that the test materials can be held enough and moved by the belts.

• Journal of Bio-Environment Control
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• v.14 no.1
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• pp.1-6
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• 2005

A multipurpose operating system was developed to adjust both spray times and ventilation method without a configuration of the moving path and the type of the greenhouse. The multipurpose working system proved to be a reliable system for testing the growth quality of the fruit vegetables in the greenhouse. The results are as follows. The first leaf, diameter of a stem, leaf area, and average stem diameter in the Cucumber seedling growth were repressed by high-speed ventilation, but was not repressed by spray times. The first leaf in the Tomato seedling growth was repressed as ventilation velocity was high, but the average stem diameter was not repressed. While the Tomato was given water three times a day, the diameter of a stem and the leaf area were increased as ventilation speed became higher. However, those were different other factors. The Tomato leaf area was larger when given water twice a day than that in hand spray, but showed no difference with ventilation speed. The first leaf, the diameter of a stem and the leaf area of a Red pepper were lower in automatic spraying with ventilation than those in hand spray.

• Journal of the Korea Convergence Society
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• v.13 no.2
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• pp.93-101
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• 2022

Based on the nutritional component analysis data of the Rural Development Administration, the change in the main nutrients of vegetables for 40 years from 1981 to 2021 was investigated. Nutrients that showed a decreasing tendency during the investigation period in fruit vegetables were calcium, iron, thiamine, riboflavin, and ascorbic acid, etc. In root vegetables, it tended to decrease in calcium, thiamine, riboflavin, niacin, and ascorbic acid, etc. In leaf vegetables, it tended to decrease in iron, niacin, and ascorbic acid, etc. In leaf and stem vegetables, it tended to decrease in energy, phosphorus, iron, thiamine, riboflavin, niacin, and ascorbic acid, etc. In particular, it has been confirmed that vitamin reductions such as thiamine, riboflavin, niacin, and ascorbic acid, which have important meanings in vegetable intake, have occurred in vegetables over the past 40 years.

• Journal of Life Science
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• v.9 no.5
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• pp.497-503
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• 1999

Change on the structural carbohydrate(several fiberous components) was determined by vegetables(crown daisy and butterbur)-cultivated in Ulsan, Kyungnam, Korea-as its stage of maturity developed. Samples were separated into leaf and stem, which were dried at 7$0^{\circ}C$ for 24hr, and ground to pass a 1mm screen. They were subjected to moisture, crude protein, crude fat and several dietary fiber-DF(dietary fiber, include unavaible components), NDF(neutral detergent fiber), ADF(acid detergent fiber), lignin, hemicellulose, cellulose and protein corrected NDF(c-NDF), IDF(indigestible fiber, include lignin, hemicellulose and cellulose). In general, structural carbohytrate(several dietary fiber) of vegetable was affected by the growth stage. In case of crown daisy and butterbur, dietary fiber in leaf was higher than DF in stem.

• Journal of the Korean Society of Food Science and Nutrition
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• v.18 no.4
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• pp.403-409
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• 1989

Dietary fiber(DF) content and their properties were analyzed in some common vegetables such as Squash(leaf), Water cress, Garland chrysanthemum, Leek and sweet potato(stem). DF was analyzed by the method of detergent fractionation. Values for neutral detergent fiber(NDF), acid detergent fiber(ADF), lignin, hemicellulose were obtained. NDF for most samples was $13.83%{\sim}24.31%$, ADF was $11.99%{\sim}21.03%$, lignin was around $0.56%{\sim}3.00%$, hemicellulose was about $1.33%{\sim}3.88%$, cellulose was $9.08%{\sim}14.87%$ except sweet potato(leaf) (20.47%). This paper describes two properties of the fiber-of commonly eaten vegetables ; water-holding capacity(WHC) and metal binding. The capacity of the acetone dried powder (ADP) to hold water was estimated. The WHC measurements differed from 7.49 per 9 of ADP for Water cress to 11.09 per 9 of ADP for Leek. The binding of Fe, Zn in NDF. ADF obtained from five fiber sources was examined under two pH conditions ; 1) pH2.1, 2) pH6.1. Fe, Zn binding increased with higher pH and differed from DF sources.

• Journal of Food Hygiene and Safety
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• v.32 no.4
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• pp.306-313
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• 2017

This study systemically analyzed the data on the microbial levels in fresh vegetables in Korea to identify the points to control. We scanned the studies published between 2001 and 2015 in peer-reviewed research papers on the microbial levels in fresh vegetables produced in Korea. Plant products were categorized by using the US IFSAC (Interagency Food Safety Analytics Collaboration) category. The most consumed, the non-heat treated, the epidemiological foodborne diseases sources of fresh vegetable in foodservice (KCDC data) were identified by literature review. Articles were screened using National Digital Science Library (NDSL) search engine regarding to microbial hazards in plant products. Based on the total plate count number and coliforms on the 89 data cases from 26 published articles, the total plate count number was high in the order of sprouts, leaf and stem, bulbs and roots, vine-grown, solanaceous, melons, and pome. Escherichia coli was frequently detected in leaf and stem and sprouts products. Focused on the microbial data of leek, lettuce and cabbage, the levels of total plate count, coliforms and Bacillus cereus showed the levels of 4.15~7.69 log CFU/g, 1~6.99 log CFU/g, and 0.51~3.9 log CFU/g, respectively, by 33 published papers. The levels of environmental factors affecting the microbial safety of lettuce and leek before harvest were investigated. Manure, soil, hands, scale, gloves were the major potential microbial contamination points to control. In addition, GAP (good agricultural practice), microbial testing, and improvement of irrigation methods are required to provide the safer fresh produce.

• Journal of the Korean Society of Food Science and Nutrition
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• v.43 no.9
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• pp.1369-1379
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• 2014

The physicochemical characteristics and antioxidant activities of leaf, stem, and root of ginger (Zingiber officinale R.) were determined. Nutrient composition, reducing sugar, saponin, mineral, heavy metal, total phenolic and total flavonoid contents, and antioxidant activities based on DPPH radical scavenging and FRAP assay were measured. Catechins, gingerols, shogaols, and capsaicin compositions were also determined by HPLC. The contents of water, proteins, fats, carbohydrates, fiber, and ash from ginger root were 6.4, 6.8, 3.2, 65.4, 7.3, and 18.2%, respectively. Crude fiber contents of leaf and stem were 4~5 times higher than those of root (P<0.05), and reducing sugar content of stem was about 3 times higher than those of root. Crude saponin contents were in the order of stem