• 한국식품과학회지
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• 제39권2호
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• pp.169-174
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• 2007

옥수수전분의 알칼리호화는 NaOH 첨가에 의하여 지수적으로 증가하였으며, 호화도가 급격히 증가하기 시작하는 구간을 알칼리호화 개시점으로 추정하였다. 10%(w/w) 옥수수 전분 현탁액의 $40^{\circ}C$에서 호화개시점은 24.1 meq NaOH/g starch인 반면에 $60^{\circ}C$에서는 9.8 meq NaOH/g starch이었다. 또한 옥수수전분 현탁액의 농도를 40%로 증가시킨 경우 $40^{\circ}C$에서 9.5 meq NaOH/g starch에서 호화가 개시되었다. 이와 같은 결과로부터 전분의 알칼리호화 개시농도가 전분 현탁액의 농도와 온도에 반비례하는 것을 알 수 있었다.

• 한국식품과학회지
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• 제39권6호
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• pp.637-643
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• 2007

옥수수 전분의 용해도, 아밀로오스 용출량 및 용출당 함량은 알칼리 호화도에 따라 모두 증가하였다. 알칼리호화의 경우 낮은 호화도에서도 특정 X-ray 회절각도에서의 강도 및 DSC의 호화 엔탈피가 감소하여 가열호화와는 달리 호화 초반에 전분입자의 결정질이 손상되는 것을 알 수 있었으며, 결정질이 손상됨에 따라 용출당 중의 아밀로오스의 상대적 함량이 낮아지고 호화과정중의 전분 입자크기는 거의 변하지 않았다. 또한 DSC의 흡열곡선이 호화도가 증가함에 따라 고온으로 이동하였다. 이와 같은 현상으로 미루어 볼 때 알칼리 첨가에 의하여 전분입자의 팽창보다는 약한 결정질로부터 파괴되면서 호화가 진행되는 것으로 추정된다.

• Applied Biological Chemistry
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• 제28권1호
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• pp.48-50
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• 1985

Moisture requirement for the gelatinization and degree of gelatinization of arrowroot starch were analyzed by X-ray diffractometry. The minimum moisture content for the complete gelatinization of the starch was 45%. The gelatinization of 6% starch suspension was terminated at $75^{\circ}C$.

• Applied Biological Chemistry
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• 제34권1호
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• pp.75-76
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• 1991

Bran structure and gelatinization property of upland and lowland japonica waxy brown rice were compared. Dimension, weight and number of aleurone layer were similar between upland(Nonglimna 1) and lowland(Shinsunchalbyeo) rices, but the aleurone layer and pericarp of upland rice were thicker. Water uptake rate of upland rice at $60^{\circ}C$ was lower than that of lowland one. There was no difference in intrinsic viscosity between two rice starches. Upland rice starch had lower onset temperature, narrower gelatinization temperature and lower water content lot gelatinization compared with lowland rice starch.

• 한국식품과학회지
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• 제26권6호
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• pp.696-703
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• 1994

The purpose of this study was to investigate the gelatinization properties of potato starch heated with microwave. Two types of potato starches were prepared; In group A raw potato starch was heated with microwave and in group B potato starch was isolated from potato heated with microwave. Both groups were exposed to the microwave energy in a 560W, 2,450 MHz oven for 60, 120, 180 and 300 seconds. Gelatinization behaviour by DSC made a few differences according to the ratio of starch to water. As the microwave heating time took longer, gelatinization temperature and gelatinization $enthalpy({\bigtriangleup}H_1)$ were decreased in and melting $enthalpy({\bigtriangleup}H_2)$ was increased in group A. Whereas they were increased in group B. In both groups, maximum viscosity in gelatinization by Brabender amylogram was decreased by microwave heating. Then the peak of the maximum viscosity was shifted to higher temperature and cold viscosity was slightly increased. In group A, viscosity in gelatinization and light transmittance by NaOH was increased in initial stage and gel volume in gelatinization by KSCN was decreased. On the other hand, in group B, viscosity by alkali was slightly decreased, but light transmittance by NaOH was almost never changed. Gel volume is decreased like group A.

• 산업식품공학
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• 제21권4호
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• pp.341-350
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• 2017

The relationship of in vitro starch digestibility and gel strength was investigated at various concentrations (10-30%) of rice cultivars with different amylose contents (27.9, 17.9, and 5.2%). As the rice flour concentration increased, predicted glycemic index decreased, but gel strength increased regardless of amylose contents. Gel strength correlated strongly with amylose content, whereas in vitro starch digestibility was more highly affected by rice flour concentration than by amylose contents. Moreover, the impact of degree of gelatinization on in vitro starch digestibility of high amylose rice was also examined in terms of structural features and rheological properties. The digestion rate of fully gelatinized flour was 1.7 times higher than that of native flour, while the disrupted structure with a different gelatinization degree during starch digestion was visually demonstrated through the X-ray diffraction and molecular distribution analysis. The rice flour changed from an A-type to a V-type pattern and showed difference in crystalline melting. The low molecular weight distribution increased with increasing degree of gelatinization during starch digestion. The apparent viscosity also increased with degree of gelatinization. These results demonstrated that the starch digestibility of rice was more affected by concentration than by amylose content, as well as by the degree of gelatinization due to structural difference.

• 한국식품영양과학회지
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• 제21권4호
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• pp.428-435
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• 1992

현미 전분의 고유점도는 일반계와 통일계 사이에 유의적인 차이가 없었다. 시차주사열량기에 의한 전분의 호화개시온도는 통일계보다 2$^{\circ}C$ 정도 높았고, 호화온도의 범위는 일반계가 통일계보다 유의적으로 컸으나 호화엔탈피는 유의적인 차이가 없었다. 호화에 필요한 수분함량과 아닐링 처리에 의한 호화성질은 서로 유의적인 차이를 보이지 않았다. 호화에 필요한 수분함량은 일반계의 경우 호화온도 범위와 부의 상관을, 통일계 경우에는 고유점도와 부의 상관을 보였다. 전분의 고유점도는 일반계와 통일계 모두 호화 엔탈피와 정의 상관을 보였다.

• 한국식품과학회지
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• 제23권1호
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• pp.116-121
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• 1991

밀전분의 호화와 노화에 수분함량과 sodium stearoyl-2-lactylate(SSL), sucrose ester(SE), monoglyceride(Dimodan) 같은 surfactant의 효과를 differential scanning calorimetry를 이용하여 조사하였다. 전분의 호화양상은 수분함량에 따라 다르고 수분함량이 30% 이하이면 호화가 일어나지 못하였다. 호화개시 온도는 $59{\sim}60^{\circ}C$이었으며, 노화개시 온도는 $50{\sim}55^{\circ}C$이었다. 노화된 전분의 엔탈피는 수분함량이 $40{\sim}50%$일 때 가장 컸다. Surfactant를 첨가하면 호화온도는 약간 높아졌고, amylose-lipid complex의 엔탈피는 증가하였다. Surfactant를 첨가한 전분은 저장에 따라 노화가 늦게 진행되었으나 amylose-lipid complex의 변화는 거의 없었다.

• 한국식품조리과학회지
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• 제14권3호
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• pp.213-218
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• 1998

The changes in gelatinization patterns of potato were investigated while steeping in water for 7 days at 30${\pm}$1$^{\circ}C$. The transmittance of 0.1% starch suspension was increased rapidly from 60$^{\circ}C$ in raw starch and the starch steeped for 2 days, and increased rapidly from 65$^{\circ}C$ in the starch steeped for 4 and 6 days. As the steeping period increased, the transmittance was decreased at above condition. The gelatinization temperature of the starch measured by differential scanning calorimetry was increased from 62.79$^{\circ}C$ to 63.72$^{\circ}C$ as the steeping period increased. The gelatinization enthalpy reached the maximum in the starch steeped for 4 days. By amylograph, the initial gelatinization temperature was increased from 66$^{\circ}C$ to 84$^{\circ}C$ as the steeping period increased. Peak viscosity was decreased during steeping and the starch steeped for 5 days had no peak viscosity. Peak height after cooling to 50$^{\circ}C$ was increased up to the 4th day and began to decrease. As the steeping period increased, there was much loss of birefringence at higher temperature. The crystallinity by X-ray diffraction disappeared from 65$^{\circ}C$.

• Applied Biological Chemistry
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• 제27권3호
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• pp.214-216
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• 1984

Alkali gelatinization of rice, corn, arrow root and ginger root starches at various sodium hydroxide concentrations was investigated. Critical concentrations of alkali for starch gelatinization ranged from 2.33 to 3.17 meq NaOH per gram of starch. Ginger root starch was most resistant to alkali gelatinization and arrow root starch was least stable to alkali.