• Applied Chemistry for Engineering
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• v.2 no.4
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• pp.301-310
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• 1991

Epoxy resins have been widely used for many applications along with good processibility. However, epoxy resin systems have poor hot/wet performance properties and brittleness after resin curing and have limited to apply for environmental resistant materials. In order to improve the toughness of epoxy resin, this review article deals with incorporation method of rubber and high performance thermoplastics into the matrix resin. In addition, molecular design of epoxy resin and modification of thermoplastic have been introduced for improving hot/wet properties of epoxy resin.

• Journal of the Korean Home Economics Association
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• v.19 no.3
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• pp.63-68
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• 1981

This study was to determine optimal conditions for preparing Gangjung and Sanja. Texturometer and panel test were employed to evaluated products which were prepared under varying soaking time of glutinous rice. The results are found as follows; Examination of acceptibilities of products by the panel test showed that 48 hours of soaking was the most optimal. In acceptability ratings. the second went to 2 hours, the third 24 hours, the forth 120 hours, the fifth, 72 hours, and the sixth, 96 hours. However, there was no significant difference in acceptability among various products(P>0.05). The cohesiveness and the brittleness of the highest-grade products soaking in 48 hours showed 0.09$cm^{2}$, 1.25cm, respectively by texturometer. In therms of acceptability, the cohesiveness of high-grade products read between 0.06~0.7$cm^{2}$. The brittleness of products examined was in the range of between 0.36 and 1.41cm. No significant difference was found among products prepared under varying soaking time n cohesiveness and brittleness.

• Advances in concrete construction
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• v.5 no.6
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• pp.613-624
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• 2017

In this paper, an experimental investigation was carried out to study the effect of volume fraction of fiber and maximum aggregate size on mode-I fracture parameters of high strength concrete. Total of 108 beams were tested on loading frame with three point loading, the variables in the high strength concrete beams are aggregate size (20 mm, 16 mm and 10 mm) and volume fraction of fibers (0%, 0.5%, 1% and 1.5%). The fracture parameters like fracture energy, brittleness number and fracture process zone were analyzed by the size effect method (SEM). It was found that fracture energy (Gf) increases with increasing the Maximum aggregate size and also increasing the volume of fibers, brittleness number (${\beta}$) decreases and fracture process zone (CF) increases.

• Korean journal of food and cookery science
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• v.16 no.3
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• pp.245-254
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• 2000

The purpose of this study was to provide the basic information for bread with kinds of spice. The qualities of bread added with garlic, ginger, and cinnamon powder were investigated using sensory and mechanical evaluation. The result of sensory evaluation showed that the softness, color, brittleness, hardness, and chewiness of bread were increased as the amount of garlic, ginger and cinnamon powder increased. Lightness decreased by the addition of garlic, ginger and cinnamon powder, while redness and yellowness increased. Texture measurement showed that hardness, cohesiveness, springiness, gumminess and brittleness were the lowest in the breads with 1% garlic, ginger and cinnamon powder, and increased as the added amount of spice increased. A positive correlation was observed between the sensory and mechanical properties in general, while hardness and chewiness have negative correlation with sensory properties. Sensory properties of wheat flour odor, roasted taste, springiness and swelling were positively correlated with the acceptability. Breads with 1% garlic, ginger, and cinnamon powder showed a good overall preference.

• Journal of the East Asian Society of Dietary Life
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• v.27 no.5
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• pp.529-539
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• 2017

The aim of this work was to make acorn bread containing natural antioxidants as healthy food. The amylographic characteristics, loaf volume, color, texture, and subjective preference of the acorn bread containing 5~25% of acorn flour were measured during storage at room temperature and in a freezer. The results were as follows: The loaf volume decreased with increasing the addition of acorn flour from 5% to 25%. The onset gelatinization temperature and the value at the peak point of the bread decreased according to the amount of acorn flour added. L-value decreased with the increase of acorn flour contents, but the a- and b- values increased. During the storage period at room temperature, the L, a, and b- value decreased, whereas in the freezer, the L-value decreased except for the bread containing 5~11% acorn flour. In sensory evaluation, color and taste achieved high scores at 18% addition, but low scores at 25% addition. The bitter aftertaste showed low scores according to the addition of acorn flour. The softness and chewiness decreased, but the overall acceptance increased according to the addition of acorn flour except for the bread added with 25% acorn flour. The textural measurements showed that the hardness, springiness, gumminess, and brittleness increased significantly during the storage periods. The cohesiveness, gumminess, and brittleness in room temperature storage decreased with the increase of acorn flour contents. In freezer storage, the addition of acorn flour resulted in the increase of hardness, springiness, gumminess, and brittleness during storage periods. On the other hands, the cohesiveness decreased with the addition of acorn flour. Moreover the addition of acorn flour increased significantly the hardness, gumminess, and brittleness during storage periods. As a result, the bread containing acorn flour showed reasonable textural properties during storage periods.

• Korean Journal of Food Science and Technology
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• v.13 no.4
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• pp.289-298
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• 1981

The texture characteristics, crispness and brittleness, of the barley flake developed by FRI in 1980 were measured with both sensory and instrumental methods. Bend and penetration test were done to determine those characteristics instrumentally, and compared each other and with sensory evaluation. And the changes in those characteristics with various water activity were studied, and the textural critical water activity was acquired. The shelf-life was also estimated with various packaging materials. It was found that crispness could be represented as the reciprocal of deformation and brittleness as that of fracture force in the barley flake. Both crispness and brittleness decreased as water activity increased. And the results from the penetration test correlated better with those from the sensory evaluation than the bend test's. The average shelf-life of the barley flake was 43 days in PE film and 9400 days in laminated Al foil on the basis of only textural characteristics.

• Korean Journal of Food Science and Technology
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• v.29 no.6
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• pp.1131-1137
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• 1997

The production rates of leavening gases and textures of cookies were investigated with various chemical leavening agents(baking powders). The chemical leavening agents could be divided into three group of a fast-acting group such as potassium bicarbonate, tartaric acid, aluminium ammonium sulfate, and fumaric acid, a slow-acting group such as ammonium bicarbonate, sodium bicarbonate, $glucono-{\delta}-lactone$, and ammonium chloride. and a double-acting group such as anhydro monocalcium phosphate, disodium dihydrogenpyrophosphate, and aluminium potassium sulfate according to the different production rate of gases. The leavening rate of ammonium bicarbonate, which was the highest of all leavening agents used in this experiment, was 131.25%. But its after-taste in a cookie was not good due to the residual ammonia. $Glucono-{\delta}-lactone$ only had no after-taste. The higher leavening rate, the more peaks in texture profile graph. Ammonium bicarbonate showed the most peaks in this experiment. It was found that the number of peak had correlation with brittleness of cookies $(r^2=0.8176)$ and brittleness of cookies was different as to various chemical leavening agents.

• Journal of the East Asian Society of Dietary Life
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• v.8 no.2
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• pp.162-173
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• 1998

The effect of soybean addition to the preparation of Jeung-Pyun(Korean fermented rice cake) and the fermentational characteristics of Jeung-Pyun dough were determined. Jeung-Pyun dough composed of rice 100g, soybean 20g, water 40g, salt 0.8g, sugar 15g and Tak-ju 30g was fermented for up to 20hours. the numbers of total microbes, yeasts and lactic acid bacteria in the dough during fermen-tation increased rapidly during 5 hours of fermentation, but Leuconostoc mesenteroides during 7 hours of fermentation, Generally, there were many more microbes in the Jeung-Pyun dough with soybeans than in the Jeung-Pyun dough with rice. The volume of 7 hour fermented Jeung-Pyun was most massive, especially in the soybean added Jeung-Pyun. 1% dextran-added rice Jeung-Pyun, the volume of steamed cake was increased more than that of rice Jeung-Pyun, but is was not as bulky as in the soybean-added cake. In the sensory evaluation of the test cake products, the 7 hour fermented cake was preferred by nost. As for instrumental characteristics, the 7 hour feremented Jeung-Pyun showed the lowest values for hardness and elasticity, brittleness and chewiness. The rice Jeung-Pyun showed were stored at 2$0^{\circ}C$ the hardness, brittleness and cohesiveness of rice Jeung-Pyun were respectively increased rapidly after 5 days of storage. The cohesiveness, elasticity, brittleness, chewiness, gumminess of both rice Jeung-Pyun and soybean-added Jeung-Pyun were decreased with storage time.

• Journal of the Korean Society of Food Culture
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• v.27 no.6
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• pp.695-701
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• 2012

This study was conducted to improve the quality of Kongsulgidduk prepared with soyflour and sweeteners. The quality was affected by the type of sweeteners used (sugar, syrup, honey), as well as the amount used (5-20%). Rheological properties showed that when more sugar was added to Kongsulgidduk, the hardness, gumminess and brittleness were lower. In addition, more than 10% sugar led to a significant decrease in hardness, gumminess and brittleness. The addition of honey increased the hardness, but decreased cohesiveness and brittleness of Kongsulgidduk. When color was evaluated, the L-value and a-value decreased, but the b- value increased as sugar was added. The addition of honey resulted in a decreased L-value. Sensory evaluation revealed that the addition of sugar resulted in better overall quality. The color score was highest when 5% sugar was added, while the flavor, moisture and chewiness scores were best when 10% sugar was added. Sweetness and consistency were good when 20% sugar was added. Honey improved the color, flavor and chewiness of Kongsulgidduk; however, sugar produced the best moisture, consistency and overall scores.

• Korean journal of food and cookery science
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• v.22 no.6 s.96
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• pp.882-889
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• 2006

The quality characteristics were measured, using sensory evaluation and mechanical characteristics, for the addition of different percentages of apricot juice(0%, 5%, 10%, 15%, 20%) to rice flour, in order to promote the use of and liking for the traditional Korean rice cakes. The pH was decreased with apricot juice addition, while acid was increased. The moisture contents were 36.2${\sim}$45.0% . The L-value was decreased with increasing apricot juice addition, while a- and b-values were increased. In mechanical texture characteristics, hardness, gumminess and brittleness were the highest at the 10% apricot juice level(p<.001). Springiness was also the highest at 10% level but the difference was not significant. In the sensory evaluation, the color, flavor, sourness, hardness and chewiness were increased with apricot juice addition. Apricot sulgidduk made with the addition of 10% apricot juice to rice flour was found to be the best recipe in terms of acceptability, flavor quality, taste quality, and overall quality and there was a significant difference between the samples. The springiness was negatively correlated with the cohesiveness, springiness, gumminess and brittleness while moistness was positively correlated with moisture, hardness, cohesiveness, springiness, gumminess and brittleness.