• 한국작물학회지
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• 제44권1호
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• pp.64-69
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• 1999

Gelatinization characteristics of 111 glutinous rice varieties were evaluated by Rapid Visco Analyzer. Gelatinization viscosity of glutinous rice tested varied with ecotypes or varietal groups: indica, japonica, and Tongil type. Indica rice showed the highest average value of initial pasting temperature. The average values for peak, hot, and cool viscosities were highest in Tongil-type rice, and lowest in japonica rice. Japonica showed the lowest breakdown and consistency, but the highest setback value. Indica was lower in alkali digestion value (ADV), and shorter in gel length after gelatinization thanjaponica and Tongil-type. Glutinous rices tested could be divided into six groups by cluster analysis based on their gelatinization characteristics. Group I-A was mostly early maturing japonica varieties while I-B was mostly indica and Tongil-type rices. Groups II-A and II-B were consisted of very early maturingjaponica, and III-A and III-B included medium or medium late maturingjaponica varieties. Group III-A showed the lowest average values of peak, hot, cool, and consistency viscosities, and also in breakdown and setback ratios. Group I-B revealed the highest values in peak, hot, cool, breakdown, and consistency viscosities. ADV was low in groups I-A, I-B, and II-B, and gel consistency was not different among the six varietal groups. Principal component analysis using seven traits related with gelatinization produced four effective components, and the first and second components were highly correlated with all the gelatinization characters evaluated.

• 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.

• 동아시아식생활학회지
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• 제23권6호
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• pp.750-759
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• 2013

In the study, purple sweet potato sponge cake was prepared with different ratios of purple sweet potato powder in order to examine the antioxidative activities and gelatinization characteristics. For DPPH radical scavenging effect, content of $IC_{50}$ came out with (+) control group of BHA. Sponge cake with purple sweet potato powder of 0% showed a range of 49.7 mg/mL, The treatment groups with purple sweet potato powder of 5~30% showed a range of 25.0 mg/mL~6.0 mg/mL. That was, the higher the added quantity of purple sweet potato powder was, antioxidative activities increased. With the higher quantity of purple sweet potato, the content of phenols and flavonoids also increased. As a result of examining the gelatinization activity with DSC, the group with purple sweet potato powder showed a faster progress in temperature for starting gelatinization compared to the control group. Gelatinization activity increased in proportion to the content of purple sweet potato powder. Based on the above study results, it was proved that there is a possibility to produce baking processed foods using purple sweet potato with stable gelatinization and excellent antioxidative activities.

• 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.

• 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.

• Journal of Ginseng Research
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• 제5권2호
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• pp.114-121
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• 1981

Starch was isolated from 4-year-old and 6-year-old ginseng roots and its physical and chemical characteristics were studied. The results obtained were summarized as follows. 1. The shape of ginseng starch granules was polygonal and rounded with its granule size ranging from 2.0 to 7.5$\mu$. The swelling power of 4-year-old ginseng starch was much greater than that of 6-year old ginseng starch. Gelatinization pattern showed that 6-year-old ginseng starch gelatinized rapidly at $65^{\circ}C$, whereas 4-year-old starch continued to gelatinize, without having a definite gelatinization temperature as temperature increased 3. Amylogram of ginseng starch showed that gelatinization initiated at 61$^{\circ}C$ and was completed at 88$^{\circ}C$ with its viscosity reaching at 810 B.U. 4. The amylose contents were 32% and 9% for 4-year-old and 6-year-old ginseng starch, respectively. 5. X-ray diffraction analyses indicated that there were some structural differences between 4-year-old and 6-year-old ginseng starch.

• Journal of Applied Biological Chemistry
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• 제66권
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• pp.90-97
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• 2023

The effect of citric acid on rice starch gelatinization and low-temperature (4 ℃) storage was studied in order to produce rice cake with a lower retrogradation rate. A citric acid solution in the ratio of 0, 0.5, 1.0, and 1.5% (w/w) of the water used during production was utilized. The gelatinization properties, gel strength, thermal properties, and texture analysis were evaluated to determine the retrogradation rate. The result showed that acid hydrolysis occurred in samples treated with citric acid. Thus, increasing citric acid decreased gelatinization temperature (58.63±1.98 to 45.84±1.24 ℃). The moduli of elasticity increased with increasing citric acid concentration, indicating an increased gel strength. Thermal analysis of starch showed that the onset, peak, and conclusion temperatures of retrogradation were increased significantly with the storage period and decreased with citric acid concentration. After 72 h of low-temperature storage (4 ℃), the retrogradation rate was lowest in the rice cake with 1.5% citric acid solution, with an increased ratio of 12.01 to 13.60% compared to the control sample, with a ratio of 12.99 to 43.54%. This shows a high retrogradation rate in the control sample. Additionally, sensory properties and retrogradation ratio suggest that the addition of 1.0% citric acid solution during rice cake production is efficient in retarding the retrogradation without an adverse effect on the rice cake modeling and acceptance.

• 한국식품영양과학회지
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• 제17권2호
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• pp.144-148
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• 1988

전분의 겔화 온도에 대한 가열속도, 수분함량 및 지방의 영향을 DSC로 측정한 결과 전분으로부터 지방이 제거됨에 따라 수분결합력이 상승함으로서 겔화 온도는 $4{\sim}5^{\circ}C$ 저하하였으며 탈지전분의 겔화 온도는 $52{\sim}67^{\circ}C$로서 옥수수, 감자, 쌀, 밀의 순으로 감소하였다. 수분함량이 증가할수록 겔화 온도는 상승하였으며 열경제적인 측면에서 전분의 겔화에 필요한 최저수분함량은 $31{\sim}41%$였다. 전분의 가열온도와 시간의 함수인 가열속도와 겔화 온도는 비례의 관계를 나타내었으며 가열속도 $15^{\circ}C/min$에서의 겔화 온도는 $5^{\circ}C/min$에 비하여 약 $2{\sim}4^{\circ}C$ 높은 값을 나타내었으며 겔화에 필요한 엔탈피도 높은 값을 나타내었다. 그러므로 가열온도와 시간의 최적화를 위하여 가열속도는 $5^{\circ}C/min$ 이하로 하는 것이 유용하리라 생각된다.

• 한국작물학회지
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• 제42권3호
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• pp.344-351
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• 1997

The experiment was conducted to examine the varietal variation in gelatinization of rice flour and adaptability to rice bread processing, and the interrelation among the relevant properties. IR 44 showed the lowest temperature of gelatinization onset(T$_{o}$ ) and the highest gelatinization enthalphy(ㅿH) measured by differential scanning calorimetry (DSC). The following lower T$_{o}$ was found with the order of Suweon 230＜Pusa-33-30＜T(N) 1, Daeribbyeo 1 and the next higher ㅿ.H was followed by the order of Pusa-33-30＞Suweon 230. IRAT 177 revealed the highest temperature of gelatinization onset and conclusion(T$_{c}$) and the following higher T$_{c}$ was found with the order of Pusa-33-30＞AC 27＞Nonganbyeo. The varietal range of T$_{o}$ and T$_{c}$ was 50.0~72.5$^{\circ}C$ and 70.2~87.4$^{\circ}C$, respectively. The rice materials tested can be classified by scatter diagram on the plane of upper two principal components contracted from DSC thermogram and various characteristics relevant to processing and sensory preference of rice bread by principal component analysis. AC27, Suweonjo and IR 44 among high-amylose rices showed better suitability to rice bread processing. The temperatures of gelatinization peak and conclusion of rice flour checked by DSC were significantly negatively associated with springiness of rice bread. The most properties relevant to processing and sensory preference of rice bread such as hardness, moistness, springiness, cohesiveness, specific loaf volume and distribution or size of air cell revealed the close correlation between each other.other.

• Applied Biological Chemistry
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• 제30권1호
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• pp.24-30
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• 1987

멥쌀 중에서 태백과 상풍 두품종으로부터 전분을 분리하고 그 전분특성을 규명하였다. 태백 전분의 아밀로스 함량은 16%, 입자의 크기는 $3{\sim}8{\mu}$인 반면 상풍 전분의 아밀로스 함량은 17%, 입자의 크기는 $3{\sim}10{\mu}$였다. 호화온도가 높아짐에따라 팽윤도와 용해도는 증가하여 $90^{\circ}C$에서의 팽윤도는 태백전분이 12.12, 상풍 전분이 11.54였으며, 용해도는 태백 전분이 3.10%, 상풍전분이 3.92%였다. 전분농도의 상승에 따라 pasting 온도의 감소는 상풍전분의 경우 보다 현저하였으며, 최대점도는 태백전분이 높은 경향이었다. 태백과 상풍전분의 희석 용액에 있어서 광투과성의 증대는 $85^{\circ}C$와 $90^{\circ}C$의 호화온도 범위내에서 주로 이루어졌다. 태백전분과 상풍전분의 호화 반응은 $60{\sim}90^{\circ}C$의 호화온도 범위에서는 2단계로 나타나고 있었다. 3단계 호화반응시의 활성화에너지는 태백전분이 26.53kcal/mole, 상풍전분이 25.14kcal/mole이었으며, 2단계 호화 반응시의 활성화 에너지는 태백전분이 $18.48{\sim}70.34kcal/mole$, 상풍전분이 $15.90{\sim}79.98kcal/mole$이었다.