• Journal of the Korean Society of Food Science and Nutrition
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• v.34 no.8
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• pp.1246-1250
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• 2005

This study was carried out to analyze the components of the stem of bush clover, Lespedeza bicolor to obtain basic data on the studies of the physiological function and a possibility of utilizing L. bicolor. General components of L. bicolor were 82.35$\%$ carbohydrate, 13.38$\%$ moisture, 2.80$\%$ crude protein, 0.86$\%$ crude ash and 0.61$\%$ crude fat. The content of reducing sugar was 147.58 mg/100 g. The total amount of free sugar was 52.4 mg/100 g that was composed of 31.0 mg/100 g fructose, 16.7 mg/100 g glucose and 4.7 mg/100 g sucrose. In the results of mineral analysis, the content of Ca was the highest (472.97 mg/100 g) and followed by 206.70mg/100 g of K. The total amount of hydrolyzed amino acid was 148.95 mg/100 g that consist of 31.74 mg/100g of essential amino acid and 117.24 mg/100 g of non-essential amino acid. Total free amino acids were contained 106.39 mg/100 g that was composed of 8.41 mg/100 g essential amino acids and 97.98 mg/100 g the non-essential, and proline (62.92 mg/100 g) was the highest that account for 59.8$\%$ of total free amino acids. Total content of amino acid derivatives was 30.01 mg/100g and that of $\gamma$ -aminoisobutyric acid was the highest as 12.57 mg/100 g among them.

• Food Science and Preservation
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• v.14 no.1
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• pp.47-53
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• 2007

Soybean curd was mixed with onion powder to develop new foods, and changes in quality characteristics were investigated. The moisture content of onion soybean curd rose as the proportion of onion powder increased Whiteness (as measured by the L value) was high in soybean cud admixed with 0.1% (w/v) onion powder, Redness (the a value) was not significantly altered (the readings were 1.03-1.54) on addition of various onion powder concentrations. Yellowness (the b value) was similarly unaffected (readings 13.00-13.93) when various levels of onion powderwere added. Free sugar analysis showed that glucose was high in soybean curd (67.22 g/100 g) admixed with 0.1% (w/v) onion powder, The main organic acid was tartaric acid, and control organic acids included citric and oxalic acids at high levels. The major free amino acids were L-arginine, ${\gamma}-Amino-n-butyric$ acid, L-histidine, L-glutamic acid, L-serine, L-tyrosine and L-threonine, and amino acid content were high in soybean curd admixed with 0.2% (w/v) onion powder. Major phenolic compounds of onion soybean curd were quercitrin, protocatechuic acid and caffeic acid. The hardness of onion soybean curd was similar to that of the control when onion powder was added to 0.1% or 0.2% (w/v), and decreasedmore onion powder was added. Organoleptic qualities dropped as onion powder levels increased. In summary, onion powder addition to soybean curd is optimal at the 0.2% (w/v) level..

• Korean Journal of Food Science and Technology
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• v.43 no.1
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• pp.58-64
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• 2011

The purpose of this study was to analyze the content and consumption of total sugar from school lunches at Incheon and Chuncheon. The samples were collected from eight elementary schools and eight middle schools in Incheon and Chuncheon for 15 days. The analysis of total sugar content was performed for 1334 main dishes, side dishes, and desserts, which were supplied by elementary and middle school foodservices. Total sugar content was extracted from various types of food with 50% ethanol after defatting. We simultaneously analyzed sugars such as fructose, glucose, sucrose, maltose, and lactose by a high performance liquid chromatography with refractive index detector. The average lunch intake for elementary school and middle school students was $372.6{\pm}72.2g$ and $449.2{\pm}81.1g$, respectively. The total sugar content in desserts was $7.21{\pm}6.32g/100g$, $1.69{\pm}2.44g/100g$ in side dishes, and $0.32{\pm}0.77g/100g$ in main dishes. Among side dishes, fried foods, stir-fried foods, and sauces contained the highest amounts of total sugar. The total sugar intake was $4.63{\pm}5.11g$ in desserts, $0.64{\pm}1.01g$ in side dishes, and $0.55{\pm}1.48g$ in main dishes. Main and side dishes with a high total sugar intake included cooked rice with seasoning, fried foods, stir-fried foods, and preserved foods. The average total sugar intake per meal for elementary school, middle school, and all students was $4.03{\pm}3.67g$, $6.97{\pm}6.59g$, and $5.50{\pm}5.53g$, respectively. We have provided useful information to decrease the intake of total sugar in school lunches. It is recommended that total sugar intake be continuously monitored.

• Korean Journal of Food Science and Technology
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• v.28 no.3
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• pp.428-432
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• 1996

The chemical components of Korean loquat (Eriobotrya japonica Lindl.) fruit were analysed. Approximate compositions of loquat flesh and seed were as follows. respectively crude lipid 0.53% and 0.83%, crude protein 0.05% and 5.27%, crude fiber 3.46% and 3.49%, crude ash 3.24% and 2.78%, carbohydrate 92.72% and 87.63% Soluble solids content, pH and acidity (citric acid) of loquat flesh juice were $12^{\circ}Bx$ by saccharometer, 4.43 and 0.18%, respectively. Free sugar compositions of loquat flesh and seed extracts $(3^{\circ}Bx)$ were as follows, respectively; fructose 0.77% and 0.31%, glucose 0.73% and 0.79%, sucrose 0.52% and 0.19%, ribose and 0.56%, Loquat flesh contained Glu 336.72 mg%, Asp 251.06 mg%, Arg 30.90 mg% and Lys 5.26 mg% Loquat seed contained Glu 448.23 mg%, Asp 335.63 mg%, lle 44.20 mg% and His 37.89 mg%, Potassium (k) contents of loquat flesh and seed were 32627.95 mg% and 28936.28 mg% in total amount of crude ash, while vitamin A and C of loquat flesh and seed were not detected. Composition of major lipid of loquat fruit seed oils fractionated by silicic acid was neutral lipids 43.78%, glycolipids 12.32% and phospholipids 43.90%, Fatty acid compositions of loquat seed lipid extracted by chloroform-methanol (2 : 1) were as follow; palmitic acid 23.72%, stearic acid 3.815, oleic acid 8.55%, linoleic acid 54.29% and linolenic acid 9.63%, Neutral lipids consist of palmitic acid 28.89, stearic acid 6.80%, oleic acid 11.07%, linoleic acid 40.67% and linolenic acid 12.58%, Glycolopids cinsist of palmitic acid 13.21%, stearic acid 4.56%, oleic acid 6.53%, linoleic acid 64.92% and linolenic aicd 10.77% Phospholipids consist of palmitic acid 30.95%, stearic acid 3.40%, oleic acid 9.09%, linoleic acid 48.45% and linolenic acid 8.10%.

• Korean Journal of Plant Resources
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• v.16 no.3
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• pp.264-274
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• 2003

Many potato genetic resources have been collected and improved for their diverse traits over the years using breeding program in KPGR. To select potential varieties for table and processing in Korea, 58 elite potato breeding lines and several 'Valley' varieties were cultivated and harvested at Korea Alpine area in 2001. The cultivated lines and varieties were evaluated using their cultural adaptability in the environment and tuber characteristics, such as the depth of tuber eye, tuber shape, skin color, flesh color, scab resistance, yield, and the resistance of hollow heart and internal brown spot disease. Additionally, in the selection of potential processing varieties, reducing sugar content (sum of glucose and fructose concentration) of tubers is critically considered, because it mainly influence on the chip color of processing potato tuber. For table stock varieties with white skin color, 'Early Valley', 'Summer Valley', 'Winter Valley', and 'Taebok Valley' were selected. In the aspect of diverse potato tuber color, several varieties were selected such as 'Golden Valley' for its yellow fresh and skin color, 'Gogu Valley', 'Juice Valley', and 'Rose Valley' for their red skin color, and 'Purple Valley' for its purple skin. Compared with world wide known processing cultivar 'Atlantic', 24 lines (or varieties) were selected for the potential potato processing industry due to their low reducing sugar contents (below 0.3％), high yield (above 4.0 ton/ha), and unique chip colors. Selected white chipping varieties were 'Taedong Valley', 'Kangshim Valley', and 'Kangwon Valley', which have 0.23％, 0.27％, and 0.29％ of reducing sugar contents, respectively. 'Bora Valley', having deep purple color in both skin and fresh, was selected for purple chip variety and has 0.26％ of reducing sugar content. Light yellow chip varieties (lines) were 'Rose Valley' and Valley 54, having 0.19％ and 0.269％ of reducing sugar content, respectively. For French frying potatoes, 'Stick Valley' of 0.22％ and Valley 72 of 0.151％ in reducing sugars were selected. All of these selected lines and 'Valley' varieties can be used as parents to improve potato genetic resources and to develop better varieties with unique traits and colors.

• Journal of the Korean Society of Food Science and Nutrition
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• v.39 no.10
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• pp.1545-1554
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• 2010

Korean government will set up the nationwide food safety system with strict control of hazardous nutrients like sugar, fatty acids and sodium as well as advanced nutrition education system. In addition, almost one hundred percent of school food service rate forced the government to consider more effective ways to upgrade the nutritional status of school meals. The object of our study was to provide the data on content and consumption of sugar in school meal for the nationwide project. For this purpose, we surveyed the sugar content of 842 school meal menus and their intake level for 154 days in 8 schools in Daejeon and Chungcheong Province. Sugar contents, the sum of the quantity of 5 sugars commonly detected in food, were analysed with HPLC-RID (Refractive Index Detector). Sugar intakes were calculated by multiplying the intake of each menu to the sugar content of that menu. The sugar content was highest in the desserts, which include fruit juices, dairy products and fruits. Sugar content of side dish was high in sauces and braised foods. Sugar intake from one dish is high in beverage and dairy product, and one dish meals contribute greatly to sugar intake because of their large amount of meal intake. The average lunch meal intakes of second grade and fifth grade elementary school students were 244 g/meal and 304 g/meal, respectively. The meal intake of middle school student was 401 g/meal. The average sugar intake from one day school lunch was 4.22 g (4.03 g on elementary and 5.31 g on middle school student), which is less than 10% of daily sugar reference value for Koreans. The result of this study provides exact data of sugar intake pattern based on the content of sugar which is matched directly to the meals consumed by the students.

• Food Science and Preservation
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• v.21 no.3
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• pp.373-380
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• 2014

This study was conducted to investigate the nutritional components and antioxidant activities of Nelumbo nucifera Gaertner flower (lotus flower, LF) and its wine (lotus flower wine, LF wine). The moisture, crude protein, crude fat, crude ash, and carbohydrate contents of the LF were 85.90, 1.91, 0.30, 1.04, and 10.85%, respectively, and of the LF wine, 92.87, 1.70, 0.30, 0.15, and 5.17%, respectively. The total amino acids in the LF and the LF wine were 2,168 and 6,341 mg/kg, respectively. Palmitic acid (38.63%) was a major fatty acid in the crude fat of the LF, and oleic acid (76.24%) was a major fatty acid in the crude fat of the LF wine. The levels of potassium in the LF ($390.91{\pm}9.60mg/100g$) and the LF wine ($27.40{\pm}1.86mg/100g$) were higher than those of the other minerals. The total phenol and flavonoid contents of both the lotus flower water extract (LFW) and the lotus flower ethanol extract (LFE) were higher than those of the LF wine. In addition, the highest antioxidant activities and ORAC values were obtained from the LFW and the LFE. In conclusion, we found that the LF and the LF wine have potential as natural antioxidants due to their higher bioactive compound contents such as their total phenol and flavonoid contents.

• Food Science and Preservation
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• v.25 no.1
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• pp.44-51
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• 2018

The purpose of this study is to present the results as basic data for establishing proper storage conditions and distribution conditions of actual farms at point of increasing concern about hygiene and palatabiltiy of consumers to food. In this study, three farmhouses of dried persimmons prepared using different storage conditions were selected in Sangju (Korea). The dried persimmons were stored for 90 days. Changes in temperature and humidity were measured with a temperature and humidity recorder under each storage condition, and physicochemical analysis and sensory evaluation were performed. The average temperatures of farmhouse A, B and C were approximately $-22--23^{\circ}C$, $-19--18^{\circ}C$ and $-25^{\circ}C$ respectively. The humidities of A, B and C were 62-63%, 59-60%, and 66-67%, respectively, and the moisture contents of all farmhouses increased during the storage period, with farmhouse B showing the most rapid increase. Free sugars increased, except for those from farmhouse C. Persimmons from farmhouse B showed the greatest changes in chewiness and hardness. The values of $a^*$ and $b^*$ were significantly decreased in persimmons from farmhouse B, and the color difference value of farmhouse B was dramatically increased. Sensory evaluation showed that the color preference tended to decrease compared with the initial value. Only farmhouse B showed decreased overall acceptability. Moreover, farmhouse B had the highest storage temperature and lowest humidity. Therefore, our results showed that storage at a low temperature and high humidity was important for manufacturing high-quality dried persimmons.

• Horticultural Science & Technology
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• v.30 no.4
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• pp.345-356
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• 2012

We investigated the changes of fruit quality parameters, polysaccharide contents and cell wall components during maturation and ripening of two Korean pear cultivar 'Hanareum' and 'Manpungbae' compared with 'Niitaka' pear (Pyrus pyrifolia Nakai) which showed different physiological maturity based on days after full bloom (DAFB). Flesh firmness decreased continuously with fruit development and maturation, reaching a final level of 29.4, 33.5, and 27.4N at maturity in 'Hanareum' (127 DAFB), 'Manpungbae' (163 DAFB), and 'Niitaka' (170 DAFB), respectively. The level of ethylene production was very low in early season 'Hanareum' pear which showed at most 0.39 ${\mu}L{\cdot}L^{-1}$ at maturity and no ethylene was detected in 'Manpungbae' and 'Niitaka' at maturity. Fructose was the most abundant soluble sugar during fruit maturation in the pears tested and an increase of sucrose was observed during fruit ripening in the Asian pears commonly. Ethanol insoluble solids (EIS) content decreased gradually with different levels among the pear cultivars as fruit ripens consisted of 10.79, 12.72, and 12.75 $mg{\cdot}g^{-1}$ FW. The amount of total soluble polyuronides was higher in early season cultivars 'Hanareum' than those of mid-season cultivar 'Manpungbae' and 'Niitaka'. In 'Niitaka' which harvested most late season, the level of 4% KOH soluble hemicelluloses was lower than 'Hanareum' and 'Manpungbae' and maintained constantly during fruit ripening period. Cellulosic residues were determined high level in 'Niitaka' which showed 612.33 ${\mu}g{\cdot}mg^{-1}$ EIS at maturity when compared with 'Hanareum' (408.0 ${\mu}g{\cdot}mg^{-1}$ EIS) and 'Manpungbae' (538.67 ${\mu}g{\cdot}mg^{-1}$ EIS). The main constituents of cell wall neutral sugars which consisted of arabinose, xylose, galactose, and glucose were decreased gradually with onset of fruit ripening regardless of cultivar. Arabinose which was predominant in 'Hanareum' pear decreased at the last stage of ripening, but the changes of cell wall neutral sugar during ripening were not occurred in 'Niitaka' pear. The change of molecular mass distribution in water soluble pectin observed dominantly at the early stage of fruit development. Depolymerization of 4% KOH-soluble hemicelluloses and degradation of xyloglucan showed in early-season cultivar 'Hanareum' during fruit maturation, and degradation of those fractions were detected only at the early stage fruit development in mid-season cultivar 'Manpungbae' and 'Niitaka'. The molecular mass profile of CDTA soluble pectin, $Na_2CO_3$-SP and 24% KOH soluble hemicelluloses showed no significant change during fruit maturation regardless of cultivar.

• Korean Journal of Food Science and Technology
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• v.44 no.4
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• pp.393-400
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• 2012

Compositional changes of the Korean chestnut (Castanea crenata) including Daebo, Tsukuba, Tanzawa and Okkwang were investigated in order to characterize them from different periods (immature, mature and storage period). Proximate compositions of mature cultivars were higher than that of the immature cultivars. Between minerals, K (263.0-420.6 mg/100 g) and P (45.8-69.6 mg/100 g) of Tanzawa were highest, and they gradually increased during storage. Tsukuba, in mature period, showed the highest contents of total essential amino acids and glutamic acids as savory amino acids. Major fatty acids were palmitic acid and linolenic acid in four cultivars. In addition, linoleic acids, as ${\omega}$-6 fatty acids, were increased during the storage period. Tanzawa, in the mature period, presented the highest levels of sucrose, however, tsukuba, in the storage period, showed relatively higher free sugar content than others. ${\beta}$-Carotene, as a provitamin A, of Tsukuba in the mature period was highly detected among them, and vitamin C of Tsukuba and Tanzawa was more plentiful than others.