• Journal of the Korea institute for structural maintenance and inspection
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• v.18 no.4
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• pp.126-137
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• 2014

Characteristics of heating and drying of Canadian-imported Douglas-fir timber using microwave in order to secure convenience and quality of drying timber and to get basic data for secondary conservation treatment are as follows: As the results of analysis of change curves of internal temperature of the timber after irradiating it, round timber and board timber showed stable heat distribution, heat consumption and surface water-content in heating with 30kW for 30 minutes and 120 minutes and with 40kW for 3 minutes and 9 minutes, respectively. Especially, surface water-content distribution according to heating by microwave showed very even leveling and water-content decrease rate was also more 30% compared to its weight showing excellent dry efficiency. And in case of soaking timbers into liquid chemicals for secondary conservation according to the analysis results of heat consumption, it is expected that large amount of preservative will be permeated. Therefore, timber heated by microwave is remarkably available for using industrial materials and developing secondary utilized products with its fast water-content decrease and dryness and higher heat consumption.

• 보존과학연구
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• s.33
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• pp.99-108
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• 2012

The white-rot fungus (Trametes versicolor) and brown-rot fungus (Tyromyces palustris), which cause damage to a variety of wooden cultural properties and buildings, such as drying of the wood tissue, decay and cracks, sponge, and discoloration, give rise to serious structural and aesthetic problems. Moreover, pest termites (Reticulitermes speratus kyushuensis Morimoto) can cause damages like hollowing the outdoor beams or pillars of wooden buildings and finally causing such buildings to collapse due to the termites' destruction of the inside of the beams or pillars, leaving only a thin layer on their surfaces. This study was conducted to determine the impact of the wood-decay fungus, a representative damage-causing microorganism, and of insects and termites on the termite ecology. The damage ratio was calculated as the weight of the timber, and the overall total mass was reduced from two kinds of rot fungi. The white-rot fungi reduced the total wood mass, but the brown-rot fungi were observed to have had an increasing tendency to do so. The wood mass was measured after drying to determine the destruction capacity of termites. As a result, the wood mass consumed by the brown-rot fungi was shown to be greater.

• Polymer(Korea)
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• v.30 no.6
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• pp.478-485
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• 2006

Physical properties and flammability of polyhydroxyamides (PHAs) haying poly (ethylene-glycol) methyl ether (MPEG) and/or dimethylphenoxy pendants were studied by using DSC, TGA, FTIR, pyrolysis combustion flow calorimeter (PCFC), and X-ray diffractometer. The degradation temperatures of the polymers were recorded in the ranges of $276{\sim}396^{\circ}C$ in air. PCFC results showed that the heat release (HR) capacity and total heat release (total HR) values of the PHAs were increased with in-creasing molecular weight of MPEG. In case of M-PHA 2 annealed at $290^{\circ}C$, the values of HR capacity were siginificantly decreased from 253 to 42 J/gK, and 60% weight loss temperatures increased from 408 to $856^{\circ}C$ with an annealing temperature. The activation energy for the decomposition reaction of the PHAs showed in the range of $129.3{\sim}235.1kJ/mol$, which increased with increasing conversion. Tensile modulus of PHAs were decreased as increasing chain of MPEG, and showed an increase more than initial modulus after converted to PBOs.

• Journal of the Korean Society of Food Science and Nutrition
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• v.44 no.7
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• pp.1072-1078
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• 2015

To maintain high quality and microbiological safety of paprika during storage for export, paprika samples after harvest were treated with 75 ppmv chlorine dioxide ($ClO_2$) gas and stored at $8^{\circ}C$, which is the optimal storage temperature, for 30 days. $ClO_2$ gas treatment reduced initial populations of total aerobic bacteria in samples by 1.62 log CFU/g as well as yeast and molds by 1.45 log CFU/g compared to those of the control. During storage, weight loss of all samples increased, and samples treated with $ClO_2$ gas showed lower weight loss than the control. In addition, total soluble solid and total phenolic contents were not significantly different between the samples during storage, whereas vitamin C content and hardness of all samples decreased. Hunter L, a, and b values of paprika samples were not significantly different between the treatments. These results suggest that $ClO_2$ gas treatment can be effective for improving microbiological safety and maintaining high quality of paprika during storage.

• Food Science and Preservation
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• v.16 no.1
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• pp.68-74
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• 2009

This study investigated the quality characteristics of breads made with addition of lotus(Nelumbo nucifera) seeds powder. Breads were prepared with 0, 5, 10, 15 and 20%(w/w) lotus seed powder instead of wheat flour. The moisture, crude protein, crude fat, crude ash and crude fiber contents of the breads increased as the proportion of lotus seed powder increased. The pH of the breads increased as lotus seed powder levels increased. The weight of breads increased with increasing lotus seed powder levels, whereas volume decreased. The specific volumes of breads with lotus seed powder were in the range of $3.59{\sim}4.68\;mL/g$, whereas the control value was 5.12 mL/g. The baking loss rates of breads prepared with 5%, 15% and 20% lotus seed powder were 8.95%, 8.17% and 7.67%, respectively. Lightness (L value) of breads was decreased by addition of lotus seed powder, whereas redness (a value) and yellowness (b value) increased in crumb and crust. Texture measurements showed that hardness and gumminess increased with increased lotus seed powder levels, but springiness decreased. In sensory evaluation, the highest scores for flavor, taste and overall preference were obtained when lotus seed powder content was 10%, and color and texture were the best when 5% of lotus seed powder was added. Thus, addition of $5{\sim}10%$ lotus seed powder may have a role in functional bread preparation, resulting in improved quality.

• Food Science and Preservation
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• v.23 no.7
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• pp.913-922
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• 2016

The aim of this study was to develop a new salting condition that included added maltodextrin (MD) and grape seed extract (GSE) to ensure the microbiological safety and quality of salted shredded Korean cabbage. Response surface methodology (RSM) was used to analyze the effects of four independent variables (NaCl concentration, salting duration, MD concentration, and GSE concentration). The following response variables were evaluated: reduction in total aerobic bacteria, yeast, and mold counts; weight loss and salt content; and taste, texture, and overall acceptability of salted shredded Korean cabbage. The optimal salting conditions include a combination of 10.09~10.32% NaCl, 9.45~10.00% MD, and 234~300 ppm GSE in a ternary salting solution and a salting duration of 5.68~5.94 hr. This optimal combination reduced total aerobic bacterial and yeast/molds counts by 3.33 and 1.45 log CFU/g, respectively, while maintaining high sensory scores for taste, texture, and overall acceptability of the salted shredded Korean cabbage. In addition, the optimal conditions yielded more acceptable weight loss and salt content characteristics. The results suggest that use of the optimized combination of salting conditions can improve the microbiological safety and quality of salted shredded Korean cabbage used for commercial kimchi production.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.26 no.1
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• pp.96-102
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• 1981

Effect of shifting planting-time and different nitrogen on the yield and characteristics of plant growth in safflower, Chrthamus Tinctorius L. This study was carried out to investigate the optimum sowing-date and the ecological variations due to differerent amount of nitrogen for safflower on the Experiment Farm of Sang Ji college from March 17 to may 16, 1980, sowing seeds with an interval of 10 days and the amount of nitrogen were applied in 5 levels (Non, half-standard, standard, one and half-ordinary amount-No and twice amount). The triple super phosphate and pottassium chloride were applied only in standard amount. The results obtained are summarized as follows; 1. As sowing-date was delayed, the germination-ratio decreased, germinating speed increased, and the time required to attain the most vigorous germinating stage and days required for germination shortened. 2. Plant height, number of branch and stem diameter showed a decrease as sowing-date was delayed. And at the same time, plant height and number of branch showed a tendency to increase as amount of nitrogen was increased. 3. As sowing-date was delayed, the number of pods and the weight of 1000-grains were decreased. Moreover, the earlier sowing-date was, the more it increased. And as amount of nitrogen was increased, number of pods and yield also were strikingly increased. 4. The fresh-weight of flower with orange and orange-red colour, as influenced by the different sowing-date, was found out to be largest at the begining of April. But increasing amount of nitrogen did not show influence upon the promotion of flowering. 5. Judging from the results reported above, the optimum sowing-date of safflower seemed to be the begining of April; also the culture of safflower seemed to be the effects of much amount of nitrogen.

• Journal of the Korean Society of Food Science and Nutrition
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• v.30 no.5
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• pp.882-887
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• 2001

The purpose of this study was to investigated quality properties of breads prepared from wheat flour with persimon leaf power. Results showed that the volume of bread was lessened, the weight of bread went up, and baking loss rate diminished as persimmon leaf powder content incremented. The experiment showed that bread was maintained in the low level of springiness and cohesiveness was relatively reduced as time lapsed, whereas 3.0 and 5.0% test group remained significantly high level. There was a rapid increment in chewiness and gumminess, which tended to show significantly low as compared to control group, Results of sensory evaluation showed that the preference scores decreased as the persimmon leaf powder contents increased (p<0.05), flavor made no significant differences up to 3.0% test group, however, 5.0% test group containing elutionsuch as catechin or tannin produced sour and bitter taste so strongly that made if feel uncomfortable with. The augment of content indicated a low prederence in terms of texture, in an overall preference had no significant differences as compared to the control group, and 0.5% test group. Through the results of these of these experiments, we can conclude that the highest quality of persimmon leaf powder content is no more than 0.5% in making bread added with persimmon leaf powder.

• Korean Journal of Food Science and Technology
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• v.50 no.6
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• pp.614-620
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• 2018

A rice bran physically treated to increase the residual gamma amino butyric acid (GABA) content (200 mg/100 g) or its hot-water extract (200 mg/100 g) was added into a white pan bread, and changes in the physical properties including color, and volume and texture changes during storage at room temperature were examined. The addition of bran powders had negative effects on bread quality and storage stability whereas that of rice bran extract (RBE) improved the storage stability of bread. The lightness of bread crumbs decreased but the volume of bread slightly increased after addition of the RBE. The increase in crumb hardness during storage was retarded by the RBE addition. The residual concentration of GABA in bread was increased 38-fold when 20% of RBE was added. The addition of RBE to white pan bread improved the resistance to staling and health-promoting function because of GABA.

• Current Research on Agriculture and Life Sciences
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• v.1
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• pp.151-158
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• 1983

This study was performed to obtain a basic materials for improvement of garlic storage ability. The "Namhae jaerae" of southern strain and the "Dalsung jaerae" of northern strain were harvested by period, their stems were cut at 7cm and 25cm from disk and then placed them in blast drying system 12 hours per day at $40^{\circ}C$ for 4 days, or in natural state. The decrease rate of bulb weight was compared and rooting, sprouting, the rate of decay was investigated between natural dry(conventional method) and hot-air dry (blast drying system). The results obtained were as follows. In the case of the decrease rate of bulb weight after hot-air dry; 7cm plot" "Namhae jaerae" was similiar to one of 13th day of natural dry and 25cm plot 14th day. In "Dalsung jaerae" 7cm plot of early, common and late harvest was respectively similiar to one of 22nd, 18th and 16th day of natural dry, 25cm plot of early, common and late harvest showed the same decrease rate of bulb weight as that of 18th, 16th and 14th day of natural dry respectively. In the case of rooting and sprouting in sand culture at the early period of storage, hot-air dry showed more prolonged tendency than conventional drying method. In the case of clove state in the latter period of storage, number of eatable cloves was more numerous and number of decayed cloves were less in blast drying system than in conventional method.