• 공업화학
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• 제2권4호
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• pp.301-310
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• 1991

대표적인 열가소성 수지인 에폭시 수지는 그 용도 및 응용분야가 광범위하지만, 경화 후 수지의 brittleness와 고온 및 습윤하에서 물성이 좋지 않아 시용에 제한을 받고 있다. 본고에서는 수지의 최대결점인 brittleness 개선과 고온 습윤 특성의 향상 방법에 대해 고찰하였다. Brittleness 개선 방법으로는 rubber 및 열가소성 수지를 에폭시 수지에 도입하여, 이에 따른 toughness 향상 정도를 중점적으로 다루었으며, 고온 습윤 특성을 향상시키기 위해 에폭시 수지의 molecular design 및 열가소성 수지의 응용방법에 대해 기술하였다.

• 대한가정학회지
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• 제19권3호
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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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• 제5권6호
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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.

• 한국식품조리과학회지
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• 제16권3호
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• pp.245-254
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• 2000

마늘분, 생강분, 계피분의 첨가량을 달리하여 제조한 식빵의 품질특성 비교 결과는 다음과 같다. 관능검사에서 마늘분, 생강분, 계피분의 첨가량이 증가할수록 외관의 부드러운 정도(softness)와 색상(color)이 강하다고 평가되었으며, 질감특성의 바삭바삭한 정도(brittle), 경도(hardness), 씹힘성(chewiness)도 첨가량이 증가할수록 높게 나타났다. 기호도면에서는 향신료의 첨가량이 증가할수록 낮게 평가되었으며, 대조군과 마늘분, 생강분, 계피분을 각각 1% 첨가한 식빵을 가장 선호하였다. 색도 측정 결과 향신료의 첨가량이 증가할수록 명도 L값은 감소하였으며, 반면에 적색도 a값과 황색도 b값은 증가하는 경향을 보였다. Texture측정에서 전반적으로 경도(hardness), 응집성(cohesiveness), 탄력성(springiness), 껌성(gumminess), 파쇄성(brittleness) 모두 마늘분, 생강분, 계피분을 각각 1%첨가한 식빵이 가장 낮게 나타났으며, 항신료의 첨가량이 증가할수록 대조군보다 특성이 강하게 나타났다. 관능검사와 기계적검사의 상관관계 결과 명도가 높을수록 선호하였으며, 경도(hardness), 파쇄성(brittleness)이 클수록 기호도가 낮아 입안의 촉감이 부드럽고 부서지는 정도가 적으며 색상이 밝을수록 좋게 평가되었다. 관능검사와 기호도간의 상관관계에서 밀가루의 독특한 냄새, 구수한 맛, 탄력성, 부푼 정도가 높을수록 선호하는 경향을 보여 향신료 특유의 냄새가 강하지 않고 구수하며 탄력성이 좋고 부푼정도가 좋을수록 선호하였다. 이상의 결과 마늘분, 생강분, 계피분을 각각 1% 첨가한 향신료 식빵의 품질이 높게 평가되어 식빵 제조시 향신료의 첨가량은 1%정도가 적당하다고 사료된다.

• 동아시아식생활학회지
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• 제27권5호
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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.

• 한국식품과학회지
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• 제13권4호
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• pp.289-298
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• 1981

보리 후레이크의 수분활성도에 따른 crispness와 brittleness를 bend test와 침투시험을 행하여 기기적으로 측정하였으며 이를 관능검사 결과와 비교하였다. 또한 조직감을 기준으로 하여 상품적 가치가 유지될 수 있는 임계수분활성도를 구하 였고 이를 기초를 포장재별품질수명을 측정하였다. 힘-변형 곡선에서 crispness는 1/변형, brittleness는 1/소요된 힘으로 각각 표기될 수 있었으며 침투시험이 bend test보다 관능정사 결과와 더 잘 일치하였고, 수분활성도가 증가함에 따라 crispness와 brittleness는 감소하였고 임계수분활성도는 0,48이었다. PE film으로 포장하였을 때 조직감 만을 기준으로 한 품질수명은 평균 43일이었으며 적층 Al foil로 포장하였을 때는 9400일로 추정되었다.

• 한국식품과학회지
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• 제29권6호
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• pp.1131-1137
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• 1997

팽창제 종류에 따른 시간별 가스 발생 속도 및 쿠키 텍스쳐에 대하여 살펴보았다. 본 실험에 사용된 가스 발생 장치에 의해서도 가스 발생 속도에 따라 크게 3타입으로 구분할 수 있었으며 이는 소암모늄명반을 제외하고는 문헌의 결과와 일치하였다. 속효성 평창제로는 주석산, 주석영, 후말산, 소암모늄명반이었고 이단 반응성 팽창제로는 산성피로인산나트륨, 무수모노인산칼슘, 소명반이었으며, 지효성 팽창제로는 중탄산암모늄, 중탄산나트륨, 글루코노-델타-락톤, 염화암모늄 등이었다. 제품 팽창률이 가장 높았던 것은 중탄산암모늄이었고 후미 면에서 가장 깨끗한 것은 글루코노-델타-락톤이었다. 팽창률이 높을수록 texture profile graph상에서 multi-peak를 나타내어 brittleness가 뛰어났으며 단순회귀분석에 의해, 팽창률과 brittleness간에 상관관계가 있음을 입증하였다$(r^2=0.8176)$. 중탄산암모늄을 사용한 쿠키 제품의 brittleness가 가장 높았다.

• 동아시아식생활학회지
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• 제8권2호
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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.

• 한국식생활문화학회지
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• 제27권6호
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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.

• 한국식품조리과학회지
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• 제22권6호통권96호
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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.