• 폴리머
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• 제28권6호
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• pp.519-523
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• 2004

폴리락트산과 상용성을 높이기 위해 전분에 무수 말레산을 그래프팅한 변성 전분을 제조하여 폴리락트산과 혼합하였다. DSC와 TGA 열적거동에서 폴리락트산/변성 전분 혼합체는 폴리락트산에서 관찰되는 172$^{\circ}C$에서의 용융 피크 외에 1$65^{\circ}C$에서 새로운 용융 피크가 관찰되었으며, 열분해 곡선에서는 폴리락트산/변성 전분 혼합체의 분해 온도가 보다 완만하게 감소되는 것으로 나타났다. 또한 기계적 강도의 측정에서는 폴리락트산/변성 전분이 폴리락트산/전분 혼합체와 비교하여 탄성률이 약 12% 증가하였으며, 이는 SEM 이미지에서 나타난 바와 같이 폴리락트산과 변성 전분의 계면 접착력이 향상되었기 때문으로 사료된다.

• 한국식품과학회지
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• 제32권6호
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• pp.1298-1305
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• 2000

0.1, 0.5, 1.0, 2.0% epichlorohydrin으로 가교결합시킨 감자 전분을 각각 5% 첨가한 polyethylene cast 필름을 제조하여 이들의 기계적 성질 및 열분해 특성, 생분해 특성을 분석하였다. Instron으로 측정한 필름의 기계적 성질에서는 가교결합 감자 전분으로 제조한 필름이 무처리 감자 전분으로 제조한 필름보다 인장강도, 신장율, 인장에너지 모두가 더 높게 나타나 필름의 기계적 강도가 향상되었음을 알 수 있었다. FT-IR과 Instron으로 측정한 필름의 열분해 특성에서는 가교결합 감자 전분으로 제조한 필름이 무처리 감자 전분으로 제조한 필름보다 빠르게 열분해됨이 확인되었다. 또한 필름의 생분해 특성에서도 가교결합 감자 전분으로 제조한 필름이 무처리 감자 전분으로 제조한 필름보다 생분해 정도가 더 뛰어난 것으로 나타났다.

• 한국식품조리과학회지
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• 제28권6호
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• pp.871-881
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• 2012

To compare the physicochemical and gel properties of mung bean starches prepared by different purification methods, starches from Korean Eohul variety and Chinese mung bean (MB) with or without hull using alkaline solution or water as solvent were purified. The optimum conditions for making muk were investigated. Apparent amylose and total dietary fiber contents, water binding capacity, solubility and pasting properties by RVA were analyzed. The characteristics of starch gels (10% dry basis) were measured for 0 and 4 day stored at $4^{\circ}C$. The protein and ash contents were significantly different (p<0.05) and lowered in starch from dehulled MB using alkaline solution. The starches from dehulled MB using alkaline solution showed the lowest color differences. Apparent amylose contents of Eohul and Chinese starches showed 37.06-39.03% and 31.57-32.74%, respectively. Chinese starch was higher in water binding capacity but lower in solubility at $85^{\circ}C$ than others. Peak, trough, cold, and breakdown viscosities of Eohul starch were higher than those of Chinese one. Mung bean starch gel made immediately exhibited clear and glossy appearance but became whiter like milk. The crystallinities of starch and starch gel showed A and B types, respectively. The hardness, gumminess, and resilience of starch gel made immediately and hardness, cohesiveness, gumminess, and resilience of 4 day stored gels were different significantly (p<0.05). Especially, Eohul starch gels purified from hulled MB showed higher resilience (bending property) and hardness. Therefore, it was suggested that high quality muk would be made using MB starch purified from hulled Korean mung bean using water as solvent.decreased in contain more than 20% of SGP added groups. The optimal concentration of SGP was found in the range of less than 10%.

• 한국식품조리과학회지
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• 제19권1호
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• pp.65-71
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• 2003

멥쌀전분, 찹쌀가루, 멥쌀전분으로 제조한 RS3형 저항전분의 수분 함량은 비슷하였으나, 단백질 함량, 회분 함량, 지방질 한량은 찹쌀가루가 가장 높았다. 멥쌀전분으로 제조한 RS3형 저항전분의 RS함량은 9.10% 이었다. 멥쌀전분으로 제조한 RS3형 저항전분을 첨가한 인절미 경도와 부착성을 레오메타로 측정하였을 때 저장기간과 RS3형 저항전분의 첨가량이 증가할수록 증가하였다. 관능검사 결과, RS3형 저항전분을 첨가한 인절미의 경도가 무첨가 인절미보다 높은 값을 보였으나, 탄성, 부착성, 부드러움성, 전체적인 품질은 RS3형 저항전분의 첨가량에 따라 유의적인 차이를 보이지 않았으며, 전체적인 품질은 경도와 음의 상관관계를 보였다(r＝-0.331, p＜0.05).

• Preventive Nutrition and Food Science
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• 제4권4호
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• pp.215-220
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• 1999

The Physical properties of corn starch were investigated by scanning electron microscopy, X-ray diffractometry and differential scanning calorimetry during the formation of enzyme-resistant starch(RS). Samples were studied in their native states and after annealing at 50, 55, 60 and 65℃ in excess water(starch : water=1:3) for 48hr. Starch granules became smaller and more rounded after annealing than in their native state. Annealing did not change the X-ray profile of native corn starch. After autoclaving-cooling cycles, native starch lost most of its crystallinity but annealed ones showed some of their crystallinity left as diffuse or poor B-type, which didn't relate to increasing Rs yields. During formation of RS, however, both native and annealed starches changed their X-ray profile from A-type to poor B-type of retrograded amylose. Annealing caused an increase in gelatinization temperature and enthalpy, but a narrowing of gelatinization temperature range. Only starch annealed at 65℃, however, showed a decrease in enthalpy even though its gelatinization temperature increased, which appeared to be due to the partial gelatinization in the amorphous region during annealing. Peak height index(PHI), the ratio of ΔH to Ti-To, increased by annealing. PHI values, therefore, showed the possibility as an indicator to predict RS yield which cannot be differentiated by differential scanning calorimetry and X-ray diffraction data.

• 한국식품영양과학회지
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• 제28권6호
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• pp.1260-1268
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• 1999

Physical properties were investigated in tangsuyuk batter containing different amounts of ingredients, such as wheat flour, corn starch, sodium bicarbonate, alum and water. For the response surface methodology (RSM) central composite design was used to determine the optimal ingredient ratios for viscosity, color properties(lightness, redness, yellowness, color differences) and cutting forces. There were significant differences(p<0.05) between the different batter mixtures. The lightness(L) of batter was in proportion to the increased amount of wheat flour and corn starch. Higher redness was recorded with increasing corn starch. Higher yellowness was observed with increasing wheat flour and sodium bicarbonate. Color differences were higher with increasing wheat flour, corn starch, and/or alum and decreasing water. Cutting forces were linearly increased with increasing sodium bicarbonate. From these results, it is possible to monitor the effects of ingredients on physical properties of tangsuyuk batter, and to predict their optimal ratios.

• 한국식품과학회지
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• 제24권1호
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• pp.70-73
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• 1992

옥수수 전분을 하이드록시프로필화 및 가교화시켜 변성 전분을 제조한 후 DSC, Amylograph 등을 이용하여 호화특성을 연구하고 호화액의 gel 특성을 조사하였다. 하이드록시프로필화에 의하여 옥수수 전분의 호화온도는 크게 떨어졌으며 가교화만을 시킨 전분은 호화온도가 약간 상승하였으며 호화엔탈피는 약간 감소하였다. 하이드록시프로필화와 가교화를 동시에 시켰을 때는 호화온도가 크게 떨어져 하이드록시프로필화만 시킨 것보다는 약간 높았으나 팽윤이 억제되었고 gel 조직강도는 증가하였다.

• 한국식생활문화학회지
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• 제21권2호
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• pp.171-178
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• 2006

Tarakjuk with different amylose content was made up using roasted rice flours that consisted of the highest enzyme-resistant starch (RS), while differential scanning calorimetry (DSC) was also utilized to measure the gelatinization temperature of these roasted rice flours in order to establish cooking temperature of tarakjuk. The following qualities of tarakjuk with different amylose content were studied: color, viscosity, spreadability, starch fractions involving total starch (TS), rapidly digestible starch (RDS), slowly digestible starch (SDS) and RS, in vitro starch digestibility (IVSD) and sensory properties. During experimentation, it was found that as the amylose content of the rice flour decreased, the L value of tarakjuk decreased, whereas a value increased significantly (p<0.05). Also, while viscosity showed to increase significantly (p<0.05), on the opposite end, the property of spreadability decreased. TS ranged from $15.95{\sim}17.31%$, RDS $9.36{\sim}10.16%$, SDS $5.46{\sim}6.91%$ and RS $0.33{\sim}1.07%$, on a dry basis. Although the amylose content of rice flours decreased, IVSD increased, however showing no significant difference. When testing the sensory properties of tarakjuk, color and viscosity increased, whereas clumpiness decreased. Ilpum tarakjuk showed the highest score for nutty taste and overall acceptance levels. In fact a high correlation was shown between nutty taste and overall acceptance level (p<0.01), which leads one to believe that nutty taste is a prime factor that greatly influences overall acceptance. Furthermore, viscosity was positively correlated with both a and b values, however negatively correlated with L value (p<0.05). Moreover, roasted nutty taste and overall acceptance were positively correlated with a value (p<0.05), respectively. In conclusion, the above results suggest that tarakjuk could be made by choosing the appropriate rice flour based on the nutritional or sensory purpose.

• 한국식품영양과학회지
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• 제30권3호
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• pp.450-454
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• 2001

The physical properties of ramyon made of potato starch at various levels (12, 14 16%) were investigated to find out the effect of potato starch on ramyon quality. The higher starch content in dough, the higher water content after steaming and the lower moisture content after deep frying. As the starch content increased, the magnitudes of extrusion work of cooked ramyon and capillary viscosity of ramyon soup increased but the starting temperature of gelatinization decreased. There was a good correlation ($R^2$=0.99) between extrusion work and capillary viscosity. Firmness and chewiness values measured by texture analyser decreased with increase in starch content while tenderness and overall texture preference evaluated by sensory analysis increased.

• 한국환경과학회지
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• 제22권10호
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• pp.1287-1294
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• 2013

In this study, thermoplastic starch (TPS), cross-linked starch (CS), and cross-linked starch modified with glycerol (CTPS) were prepared, and the mechanical properties of the compatibilized low-density polyethylene (LDPE) blends (LDPE/TPS, LDPE/CS, and LDPE/CTPS) were investigated and compared with those of uncompatibilized LDPE/TPS, LDPE/CS, and LDPE/CTPS blends. Maleic-anhydride-grafted polyethylene was used as the compatibilizer. The enhanced tensile strength and elongation at break for the compatibilized LDPE/modified starch blends are a result of the improved compatibility between LDPE and the modified starch, which was confirmed by torque measurements and scanning electron microscopy.