• Journal of agriculture & life science
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• v.45 no.6
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• pp.73-80
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• 2011

To investigate the characteristics of plant growth and flower quality of gerbera 'Sunny Lemon' by amount of nutrient solution, young seedling plants, 'Sunny Lemon' were transplanted to rock-wool and medium of peat moss and perlite mixed with 1 to 2 and they were acclimatized in greenhouse during about 1 month. Nutrient solution supplied to the plants is sonneveld solution of 1/2 concentration and treatments launched June 24, 2010 when average plant height was $20{\pm}1cm$. Nutrient contents as a standard for starting point of irrigation by time domain reflectometry (TDR) were determined with 60-65%, 70-75%, and 80-85%. Results of growth during vegetative growth, plant height, leaf width and leaf number increased by 10% in rockwool, but they were not significantly different. As for plant growth depending on nutrient content, 80-85% treatment showed the highest values. Leaf number increased by 60%, and leaf width and plant height had a about 40% increase than initial growth. Effectiveness for flower quality, yield and days to flowering were superior when nutrient content of media was higher than in the others. Especially, average days to flowering in 80-85% content was advanced by 7-10 days compared to the day in 60-65% treatment. The total amount of nutrient supply per plant was higher in mixed medium than in rockwool, but change patterns of EC and pH were enhanced in rockwool. Based on our results, we recommended that growth, cut flower, and yield of gerbera 'Sunny Lemon' were more effective when nutrient content of mixed medium was maintained at 80-85%.

• Journal of the Korean Applied Science and Technology
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• v.36 no.1
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• pp.324-332
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• 2019

Most countries including Korea and Indonesia have strong policy for implementing biofuels like biodiesel. Shortage of the oil feedstock is the main barrier for increasing the supply of biodiesel fuel. In this study, in order to improve the stability of feedstock supply and lower the biodiesel production cost, the feasibility of biodiesel production using two types of Indonesian tropical crop oils, pressed at different harvesting times, were investigated. R. Trisperma oils, a high productive non-edible feedstocks, were investigated to produce biodiesel by esterification and transesterification because of it's high impurity and free fatty acid contents. the kindly provided oils from Indonesia were required to perform the filtering and water removal process to increase the efficiency of the esterificaton and transesterification reactions. The esterification used heterogeneous acid catalyst, Amberlyst-15. Before the reaction, the acid value of two types oil were 41, 17 mg KOH/g respectively. After the pre-esterification reaction, the acid value of oils were 3.7, 1.8 mg KOH/g respectively, the conversions were about 90%. Free fatty acid content was reduced to below 2%. Afterwards, the transesterification was performed using KOH as the base catalyst for transesterification. The prepared biodiesel showed about 93% of FAME content, and the total glycerol content was 0.43%. It did not meet the quality specification(FAME 96.5% and Total glycerol 0.24%) since the tested oils were identified to have a uncommon fatty acid, generally not found in vegetable oils, ${\alpha}$-eleostearic acid with much contents of 10.7~33.4%. So, it is required to perform the further research on reaction optimization and product purification to meet the fuel quality standards. So if the biodiesel production technology using un-utilized non-edible feedstock oils is successfully developed, stable supply of the feedstock for biodiesel production may be possible in the future.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.63 no.3
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• pp.175-185
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• 2018

The aim of this study was to evaluate the variation of growth and quality characteristics in colored rice from 178 accessions and to develop useful, basic rice breeding data by classifying these germplasm characteristics via principal component (PC) analysis. The coefficient of variation of the 178colored rice accessions were the highest for panicle length (PL) and protein contents, followed by length-width ratio (LWR), 1000-grain weight (TGW), culm length (CL), and amylose contents, whereas the lowest was for the number of panicles per hill (NP), which is a yield component. The results from the PC analysis exhibited eigenvalues and contributions respective to each PC as follows: PC1, 2.06 and 29.49%; PC2, 1.31 and 18.75%; PC3, 1.21 and 17.36%; PC4, 1.01 and 14.38%. The eigenvalues of four PCs were over 1.0, and their cumulative contributions were 79.98%, which completes the necessary condition for evaluation of the 178 colored rice accessions. Cluster analysis showed cluster I as the largest, which included 79 accessions, while clusters II, III, IV, V, VI, and VII comprised 46, 19, 13, 4, 8, and 9 accessions, respectively. Moreover, dark brown accessions were dispersed in clusters I and II, and many resources of purple seed coat color were found in clusters V, VI, and VII. Particularly, cluster V had resources of only black and purple seed coat colors. Resources of cluster VII were found to have a relatively small average CL, PL, and LWR; notably, cluster V had the smallest average TGW, and cluster IV the lowest NP but the highest TGW. Finally, considering the yield potential, growth characteristics, heading stage, and color during breeding of colored rice, we obtained the following conclusions: cluster VII is suitable for breeding of colored rice; cross breeding among clusters I, II, and VII has a high yield potential; and it is possible to produce a superior color by cross breeding plants from cluster V and VI.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.18 no.4
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• pp.316-324
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• 1985

Vacuum-packed and seasoned smoked-dried products of red squid, Ommastrephes bartrami, caught in the Northern Pacific Ocean, were prepared and stored at room temperature for 90 days to test their keeping quality. Defrosted squids were eviscerated, skinned, and cut. The mantle meats were flavored with seasoning powders prepared from sugar, sorbitol, salt, monosodium glutamate, or smoke flavor (Smoke-EZ, Alpha Foods Co., Ltd.). After seasoning, the mantle meats were dried at $45^{\circ}C$ for 7 hours, vacuum packed in plastic film bags, and pasteurized in water at $95^{\circ}C$ for 30 minutes. Three kinds of products were prepared : control products (seasoned-dried), solid smoked seasoned-dried and liquid smoked seasoned-dried. The moisture level, water activity, color value (L, a and b value), texture, and viable cell counts of bacteria in these products were determined during storage at room temperature, $5^{\circ}C\;and\;35^{\circ}C$, respectively. The results showed that the products could be preserved at good condition for 90 days though they developed pale brown color during storage. The contents of free amino acids, nucleotides and their related compounds, and the compositions of fatty acids of raw squid and smoked products were analysed. In the amino acids, arginine, taurine, glycine and proline were abundant in raw and smoked products. The contents of hypoxanthine of raw and smoked products were higher than the other nucleotides and their related compounds. In fatty acid compositions of raw and smoked products, the dominant fatty acids were docosahexaenoic acid (22:6), hexadecanoic acid(16:0) and eicosapentaenoic acid (22:5).

• Food Science and Preservation
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• v.23 no.6
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• pp.804-810
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• 2016

This study aimed to compare the quality characteristics of developed rice Jochung (E) with those of commercial-rice Jochung (A, B, C, and D). The total soluble solid, reducing sugar, and dextrose equivalent of developed rice Jochung were $80^{\circ}Brix$, 44.53%, and 56.94%, respectively. The pH and titrable acidity were 6.25 and 0.19%, respectively. The color difference value (${\Delta}E$) of developed rice Jochung was 74.42, which was significantly lower than the other samples investigated. The light transmittance and total polyphenol contents of developed rice Jochung were 56.4%T and 108.23 mg GAE/100 g, respectively. The adhesiveness values of various commercial-rice Jochung products were 29.0~66.0 sec, while that of developed-rice Jochung was 61 sec, showing good textural properties for use in manufacturing Hangwa, a Korean traditional cookie. The electron-donating values of various rice Jochung were 20.4~50.3%, among which the developed-rice Jochung showed the highest value. The reducing powers of various rice Jochung products were 0.44~0.72, while that of the developed product was 0.72, which was significantly higher than the other values. Sensory evaluation revealed that the color scores of developed- and commercial-rice Jochung products were 6.70~6.80. Flavor scores of rice Jochung products ranged from 6.00 to 7.00. Taste and mouth feeling scores of developed-rice Jochung did not significantly differ from those of commercial Jochung products. Compared to commercial-rice Jochung products, developed-rice Jochung made with malt extract exhibited high polyphenols content. However, there were no significant differences in the overall acceptability scores between commercial-rice Jochung products and the developed product. The developed-rice Jochung analyzed in this study may be useful as a traditional sweetener for various Hangwa products as a substitute for corn syrup or Jochung.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.55 no.2
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• pp.177-186
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• 2010

This study was carried out to compare the physicochemical characteristics and preference as a sensory quality of Sogokju (Korean traditional rice wine) from waxy rice varieties. The protein and moisture contents of milled waxy rice varieties were ranged 6.9~7.2% and 12.1~ 12.6%, respectively. Nunbora had the largest grain size. In pasting properties, Hangangchalbyeo had the highest peak, trough and final viscosities, and Dongjinchalbyeo had the lowest viscosity curve. These differences suppose to be caused by the amylopectin(AP) structure: Dongjinchalbyeo has the largest short AP chains (degree of polymerization (DP) 6-12) and the smallest middle AP chains (DP 13-24) in 9 waxy rice varieties, while Hangangchalbyeo has the smallest short AP chains and the largest middle AP chains. The alcohol contents of Sogokju brewed from 9 waxy rice varieties were 17.6～19.9%. The brix degree were ranged $20.5{\sim}23.9^{\circ}Bx$. The organic acid of Sogokju consisted mainly of succinic acid, and the free sugar of it consisted mostly of glucose. The sensory evaluation showed the highest palatability at the Sogokju from Baegseolchalbyeo. The palatability was positively correlated with the brix degree, the glucose content, and the turbidity, and negatively correlated with the production yield of Sogokju.

• Journal of the Korean Society of Food Science and Nutrition
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• v.45 no.5
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• pp.723-730
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• 2016

In this study, we developed traditional liquor, Omegisul, with seaweeds to support the regional culture of Jeju Island in manufacturing traditional liquors. Seaweed extracts from Sargassum fulvellum and Hizikia fusiformis were added for manufacturing Omegisul at a final concentration of either 5 or 10% and fermented for 10 days. During fermentation, samples were collected to measure changes in quality of Omegisul including pH, acidity, alcohol content, chromaticity, total microbes, organic acid content, and antioxidant activity. Both pH and acidity of Omegisul were significantly altered in the early stages of fermentation. Alcohol contents increased over the fermentation period up to 9%. Regarding chromaticity of the product, L, a, and b values were highest in Omegisul with 10% Hizikia fusiformis. Both total plate count and lactic acid bacterial count tended to increase in the early stage of fermentation and decrease later, reaching their highest points in Omegisul with 10% Hizikia fusiformis at 10 days: $1.45{\times}10^8CFU/mL$ and $2.21{\times}10^8CFU/mL$, respectively (P<0.05). Among organic acids, lactic acid contents were significantly higher during fermentation with the highest concentration of 7.474 mg/mL in Omegisul containing 10% Sargassum fulvellum. 1,1-Diphenyl-2-picrylhydrazyl (DPPH) and 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) radical scavenging assays showed that antioxidant activity of Omegisul was increased during fermentation period. Among the samples, Omegisul with 10% Sargassum fulvellum showed the highest antioxidant activities of 69.81% and 81.61% in DPPH and ABTS assays, respectively. Taken together, Omegisul with 10% Sargassum fulvellum showed better characteristics in terms of quality than the other groups and has potential as functional Omegisul.

• Journal of the Korean Society of Food Science and Nutrition
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• v.42 no.11
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• pp.1829-1836
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• 2013

This study is carried out to investigate the physicochemical characteristics, microbial population, and sensory characteristics during fermentation of Korean traditional rice wine with addition of glutinous rice. The fed-batch fermentation of rice was performed by Nuruk and yeast for 10 days at $28^{\circ}C$ in a water bath. The four fermentation batches included 0, 10, 15 and 20% of glutinous rice based on the total rice contents. The growth of total viable cells, lactic acid bacteria (LAB), and yeasts were similar among the four batches during the fermentation period. The population for total viable cells and LAB were increased for the first 3 days, and decreased slowly until 10 days. The number of yeast cells was rapidly decreased after day 6, when the alcohol content reached about 15% for all the fermentation batches. Physicochemical characteristics, such as pH, total acidity, and reducing sugars, were not different with the increase of additional glutinous rice contents. The ethanol production was higher in Korean traditional rice wine from non-glutinous rice (17.1%) than ones from glutinous rice (15.8~16.7%). For the sensory evaluations, Korean traditional rice wine with 15% glutinous rice was highly preferred due to the highest sweetness.

• Journal of Applied Biological Chemistry
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• v.60 no.4
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• pp.383-390
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• 2017

Regarding the facts that fat, which is easily oxidized, is one of the major responsible factors affecting the quality of aroma, and polyphenol compounds including chlorogenic acid (CGA) contribute the anti-oxidative activities to coffee, we investigated fat oxidation, conversion of CGA, and changes of anti-oxidative activities according to the degree of roasting and storage of 60 days. We found that the amount of extractable fat by diethyl ether is increased as the coffee beans are roasted longer. Furthermore, the acidity values of the fat are increased from $8.91{\pm}0.16$ to $17.81{\pm}0.11$, and $10.37{\pm}0.27$ to $17.93{\pm}0.09$ in the medium and dark roasted coffee beans, respectively, while it is increased from $4.47{\pm}0.11$ to $11.89{\pm}0.18$ in the green coffee bean after 60 days. The CGA contents in the coffee beans were decreased from $310{\pm}8.2$ to $282{\pm}11.2$, then to $58{\pm}0.0mg$ in 10 gr of the green, medium and dark beans, respectively, and were not changed significantly during the storage period. However, the anti-oxidative activities measured by 2,2-diphenyl-1-picrylhydrazyl and 2,2'-azinobis-(3-ethylbenzothiazoline-6-sulfonic acid radical scavenging assays were not significantly different among the green, medium, and dark coffee beans during the storage period. Furthermore, antioxidant reactive element-luciferase assay showed that biological anti-oxidative activities were increased as coffee beans were more roasted and stored longer. As the total polyphenolic contents in the beans were significantly decreased by roasting, the results suggests that other molecules, such as, Maillard reaction products might play substantial role in anti-oxidative activity and influence cup quality of coffee.

• Food Science and Preservation
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• v.24 no.8
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• pp.1103-1112
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• 2017

This study was performed to investigate the effects of different cooking methods (boiling, roasting, stir-frying, and deep-frying) on folate retention in 6 kinds of mushrooms (Beech-, button-, Juda's ear-, oak-, oyster-, and winter-mushrooms) frequently consumed in Korea. In order to assure reliability of analytical data, trienzyme extraction-L casei method was verified and analytical quality control was also evaluated. Folate contents of mushrooms varied by 6.04-64.82 g/100 g depending on the type of mushrooms. and were significantly affected by cooking methods. Depending on cooking methods, folate contents of mushrooms decreased by 22-48%, 2-31%, and 17-56% for Juda's ear-, oak- and oyster-mushrooms, respectively, while 17-90% of folate was increased in Beech mushroom. Overall, the largest weight loss was found in boiled mushrooms, but the lowest one in deep-fried samples. True folate retention rates considering processing factor were less than 100% for all cooked mushrooms except for Beech samples. Overall, folate loss was the largest by boiling with water but the smallest by deep-frying. Both accuracy and precision of trienzyme extraction-L-casei method were excellent based on a recovery close to 100% and coefficient variations less than 3%. Quality control chart of folate analysis (n=26) obtained during the entire study and an international proficiency test (z-score=-0.5) showed that trienzyme extraction-L casei method is reliable enough for production of national folate database.