• 한국잠사곤충학회지
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• 제15권1호
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• pp.31-35
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• 1973

생사의 항장성에 관여하는 기본적인 성질은 강력 신도 및 탄성이다. 그리고 이들 3자간의 적당한 조화가 생사의 특성을 발현한다. 또 생사의 이러한 역학적 거동은 이를 구성하고 있는 견사가 지배하는 것이다. 이러한 견지에서 저자는 견사의 신장변형과정에서의 항장성에 관하여 연구하고 다음과 같은 결과를 얻었다. 1. 견층별견사의 인장강력은 내층견사가 외층 및 중층견사보다 높았다. 2. 견건조과정에 있어서 견층 sericin의 습열변성은 견사의 인장강력을 변화시킨다. 3. 신장과정에 있어서 견사의 변형량이 증가하면 elasticity index가 감소한다. 4. 다습열에 의한 견층 sericin의 변성은 견사의 elasticity 를 감소시킨다.

• 한국수산과학회지
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• 제53권5호
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• pp.672-680
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• 2020

This study investigated the physicochemical properties and antioxidant activities of yanggaeng prepared from agar, sugar, honey, oligosaccharide, cooked white bean paste, and different amounts (0, 0.5, 1.0, 1.5, 2.0, and 2.5%) of Pyropia yezoensis powder. The moisture, pH, sugar content, color, texture, antioxidant activity, and sensory properties of yanggaeng were investigated. The moisture content of yanggaeng did not change despite the increasing amount of P. yezoensis. The pH and sugar content decreased with increasing P. yezoensis concentration. The lightness decreased significantly, whereas the redness and yellowness increased with increasing amounts of P. yezoensis. Regarding texture profile analysis, the hardness, gumminess, chewiness, and cohesiveness decreased with increasing P. yezoensis content. The antioxidant activity of yanggaeng increased with increasing concentrations of P. yezoensis powder. Yanggaeng containing 2.5% P. yezoensis had the highest overall sensory acceptance score. Therefore, the addition of P. yezoensis to yanggaeng appears to improve its quality and antioxidant activity.

• 한국축산식품학회지
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• 제30권6호
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• pp.930-937
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• 2010

This study was carried out to investigate the textural and sensory properties of pork jerky with differently added sources of tenderizer or humectant at final concentrations of 2 or 5% (v/w). Pork jerky treated with 5% glycerol, kiwi, or pineapple had lower moisture content and water activity than that of control pork jerky (p<0.05). The addition of tenderizer or humectant resulted in a lower shear force than that of control (p<0.05). The addition of 2 or 5% glycerol resulted in higher equilibrium moisture content (EMC) than other treatments, and addition of tenderizer or humectant produced a higher EMC than that of control (p<0.05). Furthermore, addition of pineapple and kiwi to the samples affected the structures of the myosin heavy chain and the actin filaments of myofibrillar protein, respectively. Trained panel sensory evaluations indicated that pineapple enhanced the flavor score, whereas tenderness score was improved by the addition of tenderizer or humectant (p<0.05).

• 한국수산과학회지
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• 제18권1호
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• pp.23-28
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• 1985

The extraction rate of lipids from the chopped whole fish was studied with various solvents. Factors which can influence on the extraction rate such as temperature, moisture content, agitation speed and solvent were also examined. In the early stage of extraction, it is considered that the rapid extraction was attributed to cell destruction which occurs in chopping the whole fish and in the later stage, the extraction rate was increased linearly with extraction time. The effect of agitation on the extraction rate had a great influence on the early stage of extraction. In agitation speed of 100, 200, 300 and 500 r.p.m. the slopes of extraction curve were -0.075, -0.075, -0.069 and -0.064, respectively. Extractability between hydrophilic and hydrophobic solvent showed a great difference. It is suggested that extractability difference between acetone and isopropyl alcohol is due to acetone property which can not extract phospholipids in polar lipids. Extractability of lipids was increased with increasing temperature and decreased with increasing moisture content.

• 한국식품영양과학회지
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• 제23권2호
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• pp.328-332
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• 1994

The purpose of present paper is to compare and analyze the quality of imported Chinese products with the Korean local products in terms of proximate composition, character of external appearance , ingredient composition of dried bracken , dried radish cubers, meju , dried pollack, dried mussel , and dried brown seaweed(Undaria puinnatidifida) which were imported between Oct., and Dec. 1992 and distributed in the market. Moisture recovery of dried products resulted in changed shape and incomplete moisture recovery due to an excessive drying in consideration of hygroscopic property in the course of distribution. The amounts of water soluble brown pigment were two times greater in Korean dried pollack and bracken than those of Chinese products. The content of volatile basic nitrogen (VBN) were twice in Chinese dried pollack, and this may be due to foregin odor from a long transport time and distribution process. The contents of aflatoxin in Korean products were not detectable and these of Chinese products were 5 $\mu\textrm{g}$(%) in dried pollack, bracken and radish cuber. the remaining agricultural chemicals were not detectable in all products. Because of poor technique and facilities, the external appearance of Chinese products especially dried mussels and dried pollack were not uniformed in size and color. Discoloration and foregin substance such as hair, dust were checked , Korean products were mostly packed in small size in PP or bag, and Chinese products were packed in bulk size and distributed as a bulk.

• 한국의류학회지
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• 제37권8호
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• pp.1107-1116
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• 2013

This study examined the use of cutinase and lipase to process cotton/polyester blend fabric. Optimum treatment conditions for cutinase and lipase were investigated for cotton/polyester blend fabric. The properties of enzyme-treated fabrics were evaluated and compared in optimal treatment conditions. In addition, the possibility to provide an enzymatic finishing on blend fabrics using mixed enzymes in a two-step process were studied. The weight loss of cotton/polyester blend fabrics with Triton X-100 was 0.8% and the dyeing property of blend fabrics with calcium chloride increased by a factor of 1.2. The use of two enzymes in combination with cutinase and lipase in the presence of auxiliaries resulted in a cotton/polyester blend fabric weight loss of 0.8%. In addition, the dyeing properties of cotton/polyester blend fabrics improved by a factor of 1.5 and the moisture regain of cotton/polyester blend fabrics improved by a factor of 1.16. However, no marked loss was observed in tensile strength. The surface morphology of cotton/polyester blend fabrics is modified through a two-enzyme treatment. The treatment of cotton/polyester blend fabrics with cutinase and lipase maintains cotton strength and improves the moisture regain of polyester fabrics.

• 한국가금학회지
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• 제21권4호
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• pp.277-284
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• 1994

The functional properties of mechanically deboned chicken meat(MDCM) from whole carcass, whole carcass without exsanguination, neck without skin, leg hone, and upper back and rib were studied. Also, the effects of adding different levels of gelatin and MDCM to the comminuted meats were investigated. Proximate composition values of MDCM ranged from 54.2 to 68.6% moisture, 14.5 to 19.7% protein, 12.3 to 30.1% fat, and 1.1 to 1.3% ash. The MDCM from leg hone had a higher content of fat, and a lower contents of moisture and protein. The MDCM from neck without skin tended to be opposite to the MDCM from leg hone. The total pigment and myoglobin levels were highest in MDCM from whole carcass without exsanguination such as 3.83 and 0.29 rng /g, and those from the other parts were 1.58~2.93 mg /g and 0. 17~0.31 mg /g, respectively. The emulsifying capacity and water holding capacity were highest in MDCM from neck without skin which contained lower levels of fat, collagen and hydroxyproline, but a higher level of salt soluble protein. The emulsifying capacity of comminuted meat decreased as gelatin content increased. The extractability of hydroxyproline from gelatin showed a higher solubility in acidic solution. The MDCM could he added up to 20% level without detrimentally affecting functional properties of comminuted meats although they had less water holding capacity and cooking loss as the proportion of MDCM increased.

• 농업생명과학연구
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• 제46권1호
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• pp.153-161
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• 2012

Wheat is a very popular crop in all over the world due to the various use of wheat flour as staple foods, such as bread. As many food products are made from wheat, the property of wheat can be a determinant of the quality of final food products. Staled bread is not harmful to health but is normally rejected by consumers due to the absence of desirable sensory attributes. The phenomena of staling can be increased hardness of bread, the migration of moisture from center of bread to the crust of bread, loss of flavor and etc. The exact mechanism of staling has not been established completely. To delay or prevent staling, either addition of anti-staling agent, such as surfactant and enzyme or modification of wheat component, such as wheat starch has been adapted. The development of waxy wheat made it possible to reconstitute the starch component in bread. When the content of amylopect in was increased in bread, the loss of moisture was decreased and the reduction in softness of bread was decreased during storage. Increased retrogradation of starch did not always accompany the staling of bread indicating that the retrogradation of starch may not be a single indicator of bread staling. To find out the exact relationship between bread staling and starch retrogradation, further research is necessary.

• Journal of the Korean Wood Science and Technology
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• 제47권3호
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• pp.311-323
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• 2019

The number of newly constructed traditional Korean houses, i.e., Hanoks, and light-frame buildings is increasing. However, related research is limited owing to the lack of awareness regarding safety evaluations. Therefore, this study conducted an outdoor exposure test to accurately evaluate wooden constructions. Spruce, pine, and fir (SPF) material was monitored for a year, wherein the SPF material was artificially dried under 18% moisture content, and its physical properties and color differences were measured once a month. Large differences were observed in the material's weight and moisture content, which are indexes sensitive to daily range and rainfall; however, no significant difference was found for other basic properties in the pre and post test results. Herein, $L^*$, $a^*$, and $b^*$ values represent color differences; these values exhibited a general decrease after the test. Such differences were attributed to the loss of lignin in the wood. The color difference value was high between the months of May and July, when the daily range and rainfall significantly fluctuated. Multiple regression analysis was performed on the $a^*$ value (redness indicator), daily range, rainfall, and ultraviolet index. The results indicated that the daily range influenced redness the most. According to the estimated regression equation, the daily range and redness are positively correlated. Based on the results, the types and influence of independent variables on color difference are expected to change as the wood's duration of outdoor exposure and the amount of data obtained both increase.

• 한국식품영양학회지
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• 제36권6호
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• pp.581-587
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• 2023

Brown rice has various health benefits; however, it is more difficult to cook and has a harder texture as compared to milled rice. In this study, the effect of the sous-vide cooking method on starch retrogradation and textural properties of brown rice was investigated by comparative analysis with conventionally cooked brown rice based on moisture content assay, evaluation of the textural property analysis, and differential scanning calorimetry (DSC). The results of the study are as follows: First, the moisture content of sous-vide cooked brown rice was higher than in the conventionally cooked brown rice. Second, the sous-vide cooked brown rice has lower hardness, higher adhesiveness, and lower retrogradation enthalpy during storage than conventionally cooked brown rice. Finally, the retrogradation properties of cooked brown rice during storage were analyzed by DSC. The enthalpy increased more rapidly in the case of conventional cooked brown rice, reaching 1.58 J/g after 3 days of storage. This indicated that sous-vide cooking is effective in preventing retrogradation of rice during storage.