• Food Science and Preservation
• /
• v.17 no.5
• /
• pp.674-680
• /
• 2010

This study was carried out to investigate quality characteristics of white breads with cabbage powder(CP) (0, 2.5, 5.0, 7.5 and 10.0%). L-value was significantly decreased by addition of CP, but a and b-values were increased(p<0.05). The degree of pH of dough and bread weight increased with increasing CP concentration, while bread volume, specific volume, and baking loss rate became reduced. The hardness of the breads added with CP was higher than that of the control group. Also, In sensory analysis, the breads with CP showed generally low scores in color, flavor, taste, texture and overall acceptability compared with the control. Taken together, the 2.5%, 5.0% treatment showed similar results with the control group, as compared to other treatments. Addition of CP influenced the color, bread volume and other rheological properties, which is disadvantageous for the quality of white bread. However, compared with the control group, up to 5% CP substitution for flour didn't show significant defferences in sensory test.

• Korean Journal of Environment and Ecology
• /
• v.23 no.2
• /
• pp.161-168
• /
• 2009

This research aims at having a grip on the actual condition of vegetation distribution Byeonsanbando National Park and to propose a survey and drawing criteria for vegetation map. Thus, this research conducted a survey of the vegetation distribution on Byeonsanbando National Park through review of the literatures on vegetation surveys on the National Parks in the past and at the present and preparing criteria for survey and drawing of vegetation. The actual vegetation of Bye on san ban do National Park was classified into eight plant communities and other land; the Substitution forest, or natural forest was classified into four plant communities including Quercus variabilis community, deciduous forest, Pinus densiflora community, and mixed forest while afforested land was classified into four forest types: P. rigida forest, P. thunbergii forest, P. rigida forest, P. rigitaeda forest, P. rigida - thunbergii forest, etc. The area belonging to grade 7 in Nature Degree was found to be the largest, covering 69.1% in Byeonsanbando National Park while the area belonging to grade 9 was very rare, covering 0.36%. Thus, it is suggested that criteria for survey and drawing map needed for the systematic survey and management of vegetation in National Parks.

• Korean Journal of Microbiology
• /
• v.42 no.2
• /
• pp.156-159
• /
• 2006

A base substitution was introduced at the position 789 in Escherichia coli 16S rRNA, which was previously identified as an invariant residue for ribosome function and the ability of the mutant ribosomes to translate chloramphenicol acetyltransfernse mRNA was measured by determining the degree of resistance to chloramphenicol of cells expressing these mutant ribosomes. As expected, mutant ribosomes containing a base sub-stitution at the position 789 showed significantly reduced protein-synthesis ability and to identify a functional role played by this residue in protein synthesis, we developed an efficient genetic method to select second-site revertants in 16S rRNA that restore protein-synthesis function to these mutant ribosomes.

• Korean Journal of Food Science and Technology
• /
• v.23 no.3
• /
• pp.317-324
• /
• 1991

Gelatinization behaviours and gel properties of hydroxypropylated corn starches (HPCS) were investigated with differential scanning calorimeter, amylograph and rheometer. Gelatinization temperature of HPCS decreased as degree of substitution increased. The retrogradation of corn starch was greatly reduced by hydroxypropylation, indicating that the association of starch molecules was sterically hindered by hydroxypropyl groups. In HPCS, gel was formed slowly and gel strength decreased resulting in soft and sticky texture. Texture profiles of HPCS gels were similar to those of tapioca and waxy corn starch. HPCS has shown a remarkable increase of paste transparency compared to native corn starch.

• Korean Journal of Environmental Biology
• /
• v.37 no.2
• /
• pp.144-154
• /
• 2019

The flora of naturalized plants in historic sites, urban parks and stream of Gyeongju-si, South Korea were summarized as 84 taxa including 21 families, 59 genera, 78 species, 1 subspecies, and 5 varieties. Direct investigation was conducted in a historic site with 68 taxa, a neighborhood park with 43 taxa, a stream with 59 taxa and a small park with 42 taxa at 86 sites. Among them, 31.0% (Naturalized Degree (ND) 3) was common but not abundant, 29.8% (ND 5) was common and an abundant plant, 20.2% (ND 2) was local and not an abundant plant. 7 taxa such as Lactuca scariola, Symphyotrichum pilosum, Rumex acetosella were invasive alien species. Lactuca scariola was the most abundant with 41.9%, Symphyotrichum pilosum was more abundant around stream with 34.9%, and Rumex acetosella was abundant on historic sites or small park with 25.6% in all the surveyed sites. To prevent spread of invasive alien species, monitoring may be required, especially, in early settlement stage. A proper management plan needs to be incorporated through physical removal of those plants, substitution of soil and so on.

• Korea journal of population studies
• /
• v.35 no.2
• /
• pp.29-53
• /
• 2012

This research studies how women's hourly wages affect childbearing using data from the National Longitudinal Survey of Youth. The results of discrete time hazard model show that the relationship between women's hourly wage and fertility is dynamic. Overall relationship looks negative, but they are not consistent across education levels. Women who have a high school diploma or less have a tendency to decrease childbearing when their wages increase. But women who have some college experience or a college degree are likely to have children when their wages increase. It means that only for highly educated women who are likely to be in high paying decent jobs, the rise of income can be used as a resource for reconciling the mother's and worker's roles. Or, for less educated women who are likely to be in the low paying jobs, the rise of income is not large enough to lessen role incompatibility.

• Journal of Microbiology and Biotechnology
• /
• v.21 no.10
• /
• pp.1036-1042
• /
• 2011

The exopolysaccharide botryosphaeran ($EPS_{GLC}$; a ($1{\rightarrow}3$)($1{\rightarrow}6$)-${\beta}$-D-glucan from Botryosphaeria rhodina MAMB-05) was sulfonated to produce a water-soluble fraction ($EPS_{GLC}$-S) using pyridine and chlorosulfonic acid in formamid. This procedure was then repeated twice to produce another fraction ($EPS_{GLC}$-RS) with a higher degree of substitution (DS, 1.64). The purity of each botryosphaeran sample (unsulfonated and sulfonated) was assessed by gel filtration chromatography (Sepharose CL-4B), where each polysaccharide was eluted as a single symmetrical peak. The structures of the sulfonated and re-sulfonated botryosphaerans were investigated using ultraviolet-visible (UV-Vis), Fourier-transform infrared (FT-IR), and $^{13}C$ nuclear magnetic resonance ($^{13}C$ NMR) spectroscopies. $EPS_{GLC}$ and $EPS_{GLC}$-RS were also assayed for anticoagulation activity, and $EPS_{GLC}$-RS was identified as an anticoagulant.

• Korean Journal of Food Science and Technology
• /
• v.30 no.2
• /
• pp.379-384
• /
• 1998

Biodegradable carrageenan films and carrageenan-coated papers were developed and their characteristics of lipid permeation was investigated for possible substitution of PE-coated papers used in packaging of oily or greasy foods. Both carrageenan coated papers and free carrageenan films were highly resistant to lipid penetration. Among the carrageenans tested, ${\kappa}-carrageenan$ film showed the most resistant followed by ${\lambda}-$ and i-carrageenan films. The resistance to lipid increased as the thickness of ${\kappa}-carrageenan$ layer increased. Carrageenan coated papers with $4\;and\;5\;kg/ream\;(278m^2)$ showed the lipid resistance comparable to that of the PE-coated paper. Free films also showed the same trends of the lipid resistance as the carrageenan coated papers, but the degree of lipid resistance was approximately ten times higher than that of carrageenan coated paper. Degree of lipid penetration of carrageenan films and carrageenan-coated papers increased exponentially against time. ${\kappa}-carrageenan$ coated papers over 4 kg/ream showed to have an adequate lipid barrier property for being utilized for packaging greasy food products.

• Korean Journal of Food Science and Technology
• /
• v.23 no.2
• /
• pp.235-240
• /
• 1991

Starch phosphates were prepared from the corn starch mixed with 2% sodium tripolyphosphate by twin-screw extruder with a feed rate of 20 kg/hr and an extrusion temperature of $130^{\circ}C$, and the effects of extrusion variables on the physicochemical properties (target parameters) of starch phosphates were investigated. Interrelations of system parameters (specific mechanical energy and extrudate moisture) and rheological properities of starch was analyzed by using the response surface analysis. Degree of substitution (DS) was increased with increasing the feed moisture, and showed the maximum value at the screw of near 250 rpm, Degree of gelatinization was proportionally increased with increasing the screw speed and decreasing the feed moisture. Apparent viscosity of the paste was increased with increasing the feed moisture, but it was not significantly affected by the screw speed. It was found by scanning electron microscopy that the starch microgranules were much more degradaded, and as consequent result, the intrinsic viscosity was decreased, whereas, water solubility index was increased. The rate of retrogradation of the gels was retarded with increasing DS and decreasing viscosity.

• Food Science and Preservation
• /
• v.20 no.3
• /
• pp.317-322
• /
• 2013

This study was conducted to investigate the effects of pretreatment and different packaging methods on the physicochemical properties of cold vacuum-dried peaches. All the dried peach samples were stored such as $N_2$ gas substitution, vacuum and passive packaged with polyethylene (PE) film and oriented polypropylene (OPP)/aluminum (Al)/PE film at $40^{\circ}C$ for 50 days. The weight change, pH, soluble solids content, titratable acidity, soluble solid-acid ratio (SS/TA), delta E, browning degree and phenolic compounds were analyzed. The weight change and pH were lower in the 0.1% vitamin C-treated group and were significantly lowest in the vacuum-treated OPP/AL/PE. The soluble solids content and the SS/TA were higher in the non-treated groups than in the vitamin C-treated groups. According to the packaging methods, the $L^*$ values were higher in the vacuum, $N_2$ gas and passive package, in that order. In addition, the browning degree and the delta E value were lower in the pretreated groups and significantly lowest in the vacuum-treated OPP/AL/PE with 0.1% vitamin C group. The phenolic compounds were high for the pretreated groups, according to the packaging methods (vacuum > $N_2$ gas> passive), and the OPP/AL/PE was significantly higher than the PE. These results suggest that different packaging materials and pretreatment methods affected the quality of the dried peaches, and the vacuum-OPP/AL/PE film packaging group showed a high quality.