• Food Engineering Progress
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• v.14 no.2
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• pp.135-145
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• 2010

In order to enhance overall quality of the Backsulki, a sweet potato flour (SPF) which is rich in sugar and dietary fiber was added into the rice flour at 0, 5, 15, and 25% (w/w, db) ratios. Quality changes of the products were evaluated by storing at 5, 15, and 25$^{\circ}C$ for 4 days. Water binding capacity, swelling power, and solubility of the products increased as the SPF increased. Hunter colorimetric a- and b-value increased while L value of the products decreased as the SPF increased. Retarded retrogradation of the flour mixtures containing the SPF was shown from the DSC thermogram as indicated by the decreased $\Delta$H values. Increases in $T_{i}$ and $T_{p}$ values in relation with the starch gelatinization were shown from the DSC thermogram with a temperature margin of 15-20$^{\circ}C$ as the SPF increased. Increases in softness along with decreases in springiness and chewiness of the products were shown as the SPF increased. It was not so much the storage temperature as the added SPF affected the final texture of the products. Retarded growth of the total microbes of the products was noted by the added SPF during storage at 25$^{\circ}C$ for 3 days. Regarding the above and additional sensory preference scores of the products, a 15%(w/w) level of the SPF was suggested as optimum for the best Backsulki with improved qualities.

• The Korean Journal of Food And Nutrition
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• v.15 no.1
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• pp.12-15
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• 2002

Green tea extract(GTE) was added to pall bread, prepared by the straight-dough method, and its effects on shelf-life(moisture, pH, titratable acidity, antimicrobial activity) and sensory quality of pan bread were evaluated. The results of those characteristics for staling indicated that quality of pan bread was significantly extended by addition of GTE. Growth of microorganisms was significantly inhibited by adding GTE to pan bread, and sensory quality on pan bread added GTE was no significant differ in color, flavour, hardness, chewiness and overall-quality than that of control group(0% GTE). These results suggest that the shelf- life of pan bread was extended by GTE.

• Journal of the Korean Society of Food Science and Nutrition
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• v.45 no.10
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• pp.1467-1475
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• 2016

To make soft and less stale bread, various amounts of gelatinized wheat flour dough were added for making pan bread. In the dough process, higher gelatinized wheat flour dough showed higher consistency and dough development time but a lower dough stability time. Expansion during fermentation represented the highest value upon addition of 10% gelatinized wheat flour dough (GWFD), and this value decreased with increasing amount of gelatinized wheat flour dough. Volume of bread was the highest in the control and lowest in 30% GWFD, and there was no difference between 10% GWFD and 20% GWFD. Moisture contents of bread made with various amounts of gelatinized wheat flour dough increased with increasing gelatinized wheat flour dough amount. Color values of bread made with various gelatinized wheat flour dough were not significantly different. Chewiness, brittleness, and hardness of bread made with control and 10% GWFD showed low values, whereas bread made with 20% GWFD and 30% GWFD showed high values. During storage, chewiness, brittleness, and hardness increased with increasing storage period in whole breads, whereas breads made with 10% GWFD showed the lowest increasing rate. In the sensory strength test, chewy texture increased upon addition of gelatinized wheat flour dough. In the consumer acceptance test, 10% GWFD showed the most overall acceptance. In conclusion, bread made with 10% gelatinized wheat flour dough is desirable for increasing softness and decreasing bread staling.

• Journal of the Korean Society of Food Science and Nutrition
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• v.40 no.3
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• pp.426-434
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• 2011

In order to increase the use of rice, ginseng Garaedduks and Topokki were made and the physicochemical and sensory properties were investigated. Topokki and Garaedduks were added with 0, 1, 3 and 5% ginseng powder and stored at $20^{\circ}C$ for 48 hours. The moisture contents were not different to the increasing amount of ginseng powder and increasing storage time for 48 hours. The moisture content of Garaedduks for control and 5% added ginseng powder were 48.08% and 49.62%, respectively. The L value in color of uncooked ginseng Garaedduk decreased according to the added amount of ginseng powder, and the b value in color increased significantly according to the added amount of ginseng powder and during 48 hours storage at $20^{\circ}C$. Textural analysis, measured using a texture analyzer, of Garaedduk revealed that hardness, cohesiveness, chewiness decreased significantly and adhesiveness increased according to the added amount of ginseng powder. In sensory evaluation, 5% ginseng Garaedduk (uncooked, cooked) scored higher in overall acceptability than those of the other samples. In cooking properties, water absorption and solid contents increased according to the added amount of ginseng powder. Therefore, Garaedduk containing 5% ginseng powder was the most preferable. These results implied that the degree of retrogradation of ginseng Garaedduk might be low due to its high dietary fiber content.

• Elastomers and Composites
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• v.36 no.4
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• pp.262-267
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• 2001

Insulating rubber gloves with antibacterial and withstand voltage properties were prepared by blending the natural rubber latex(NRL), waterborne polyurethane(PU) and 4N-chitosan. Tensile strength of rubber glove increased with increasing amount of PU, and elongation decreased. The property of withstand voltage of rubber gloves improved with increasing leaching time, and the rubber gloves showed insulating capability of 10000V at leaching time of 3 hours. Little bacteria existed after 4N-chitosan was added to rubber gloves.

• Journal of the Korean Society of Propulsion Engineers
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• v.2 no.3
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• pp.62-69
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• 1998

Mechanical properties of polyethyleneglycol(PEG)/cyclo-tetramethylene tetranitramine(HMX) propellant were studied by adding polycaprolactone(PCP) and silane derivatives as coupling agent. Mechanical properties of the propellant were enhanced by increasing the content of PCP which was partially replaced with PEG. PCP/HMX propellant showed 17% increase in maximum tensile strength and 59% increase in elongation compared to those of PEG/HMX propellant. However, as the content of PCP was increased, the hydrolytic stability of this propellant was found to be deteriorated due to the ester group of PCP by measuring hardness drop of cured propellant and swell ratio difference of PEG/PCP binder stored at $40^{\cire}C$ and 90% relative humidity. Hardness of the PEG/PCP/HMX propellant was decreased with increasing triethoxysilyl propionitrile(TESPN) and dinitrosalicylic acid (DNSA) content from accelerated aging at $60^{\cire}C$.

• Proceedings of the Korean Society for Bio-Environment Control Conference
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• 2001.04b
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• pp.77-78
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• 2001

순환식 양액재배에서 근권부 배지의 종류가 작물의 양분흡수에 미치는 영향을 구명하고자 하였다. 배지별 양액흡수량은 토마토 및 오이 모두 같은 경향이었는데, 단위일사량당 양액흡수량을 보면 오이는 생육 전반기인 6월 5일까지 지속적으로 양액흡수가 이루어지다가 일사량에 따라 전체 양액의 흡수가 변화하였다. 그러나 단위일사량당 양액흡수량은 생육 후반기에 일정한 수준을 유지하였는데 이것은 노화된 하엽을 제거하였기 때문으로 보인다(Fig 1). 배지에 따른 양액흡수량은 전체적으로 암면에서 생육 후기까지 다소 높은 경향을 보였으나 통계적으로 유의성은 인정되지 않았다. 또한 배지간의 무기이온 흡수율은 이온별로 차이가 있었으나 모든 이온에서 유의성은 인정되지 않았다. 배지에 따른 무기이온 흡수량은 전체적으로 암면에서 생육 후기까지 다소 높은 경향을 보였으나 통계적으로 유의성은 인정되지 않았다(Fig. 2). 작물의 생육 및 수량에서도 암면에서 전반적으로 높은 경향을 보였으나 통계적으로 유의성을 보이지는 않았으나 오이의 엽중은 암면에서 무거웠고 엽건물중도 차이가 있었다. 기타 생육 요소간에는 유의성이 인정되지 않았지만 암면에서 다소 좋은 경향을 보였다(Table 1). 따라서 작물의 무기이온 흡수량을 추정하는 모델식의 입력요소로 배지 종류는 적합하지 않았으며 다만 수분 보유력이 좋은 암면에서 양액 흡수량이 많았다는 결과를 얻었다.

• Journal of Korean Society of Forest Science
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• v.83 no.2
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• pp.164-174
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• 1994

Temporal changes in growth performances, chlorophyll contents, and tissue water relations for determining their physiological responses of five economic tree species subjected to chronic water and nutrition stresses were investigated with containerized seedlings grown in different soil moisture regimes and nutrition levels. Seedlings of Quercus acutissima, Q. variabilis, Q. mongolica, Q. serrata, and Fraxinus rhynchophylla were propagated in plastic pots(I.D. $16cm{\times}Depth$ 16cm) for the experiments. The seedlings were subjected to two soil moisture regimes of dry and wet soils and two nutrition levels of fertilization with N+P+K and no fertilization through the growing season from May to September in a green house. For the purpose of analyzing their responses to the environmental stresses, seedling heights and root collar diameters, chlorophyll contents, and P-V curve parameters of the seedlings were measured in May, July, and September. The environmental stresses coming from moisture and nutrient deficits affected the growth performances of seedlings variously among species and among different growing periods, as well as between height and basal diameter growth of seedlings. The growth performances of Q. acutissima were influenced sensitively on the stresses, but those of Q. mongolica less influenced in comparison with other species. Chlorophyll contents were generally higher in Quercus spp. than F. rhynchophylla through the growing season. The chlorophyll contents changed by species and by treatment through the season within ranges of 0.14~1.96 mg/g dry wt. of chlorophyll a and within 0.16~1.79mg/g dry wt. of chlorophyll b, respectively. But the contents seemed to be decreased gradually through the chronic environmental stresses and leaf senescence. The osmotic potential at full turgor(${\Psi}{{\pi}o}$) and turgor loss point(${\Psi}{\pi}p$) had temporarily declined up to 3 to 5bars from -7.0~-12.4bars in May to -10.2~-17.5bars in September and up to 5 to 6bars from -7.6~-14.2bars in May to -12.9~-20.4bars in September, respectively, with some exceptions. The values of ${\Psi}{\pi}p$ were generally high in F. rhynchophylla in May and July, but high in Q. serrata in September. Relative water contents at turgor loss point(RWCp) were generally high in F. rhynchophylla, but the temporal changes of RWCp were quite and frequently different among species and among treatment.

• Korean Journal of Food Science and Technology
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• v.53 no.4
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• pp.486-494
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• 2021

A rice (Oryza sativa L.) cultivar of the SPP (stakeholder participatory program) and ordinary rice were characterized based on water-absorption properties and cooked rice texture. During rice soaking, the rice grain transformed from transparent to opaque (white), indicating that water molecules diffused into the rice grain during soaking. In addition, cracks in the internal structure of soaked rice gradually increased with an increase in soaking time. Water absorption increased rapidly up to 20 min, but no increment was observed after 30 min of soaking. At this point, the entire areas of the soaked rice grain turned white, indicating that water absorption had reached saturation. SPP rice showed lower hardness and higher stickiness in its cooked form than ordinary rice, suggesting that SPP rice could be a more preferable choice than ordinary rice. Furthermore, cooked SPP rice was more edible in terms of hardness and stickiness after being kept warm for 12 h than ordinary rice. These results indicated that cooked SPP rice exhibited slow retrogradation and improved taste.

• Journal of Life Science
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• v.27 no.9
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• pp.975-985
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• 2017

To investigate the beneficial effects of an agar gel mask (AGM) on UV-induced photoaging, SKH-1 hairless mice were treated with a topical application of AGM and an AGM dipped in essence (AGMdE). The mice were divided into an no radiation group, UV + AGM, UV + AGMdE, and UV + vehicle (PBS) treatment groups. Alterations in skin wrinkles, skin phenotype, histological structures, oxidative status, and toxicity were then evaluated during 4 weeks of exposure. The topical application of AGM and AGMdE inhibited wrinkle formation, suppressed the erythema index, prevented transepidermal water loss, and enhanced skin hydration. In addition, epidermal thickness recovered to a similar level as that in the no irradiation group in the UV + AGM and UV + AGMdE treatment groups compared with the UV + vehicle (distilled water) group. Furthermore, the expression levels of matrix metalloproteinase-1 (MMP-1) and tyrosinase were reduced in the UV + AGM and UV + AGMdE treatment groups, although the highest level varied. Moreover, superoxide dismutase (SOD) activity was significantly lower in the UV + AGM and UV + AGMdE treatment groups as compared with the UV + vehicle group. No significant alterations induced by most toxic compounds were measured in serum biochemical markers and liver and kidney histological features of the UV + AGM and UV + AGMdE treatment groups. These results suggest that AGM may protect against skin aging by regulating skin morphology, histopathological structures, and oxidative conditions.