• Food Science and Biotechnology
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• v.18 no.1
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• pp.118-123
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• 2009

In order to find out the effect of low level of starch acetylation on physicochemical properties of potato starch, amylose content, digestibility of raw and gelatinized starch, thermal properties, pasting properties, and the swelling power of native and acetylated potato starches were measured. The amylose content was significantly lower in acetylated starch than in their counterpart native starches. Though a tendency in the decrease in digestibility of raw starch was observed with starch acetylation, acetylation did not alter the proportion of readily digestible starch (RDS), slowly digestible starch (SDS), and resistant starch (RS) of both raw and gelatinized potato starches. No clear increase in the swelling power was observed, however, the peak and onset gelatinization temperatures and the enthalpy required for starch gelatinization decreased with starch acetylation. Peak and breakdown viscosities were reduced due to acetylation of potato starch while final viscosity and set back were increased.

• Food Science and Biotechnology
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• v.18 no.2
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• pp.456-462
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• 2009

In comparison to processed wheat flour products, there is no established method for determining the water absorption of rye flour. The aim of this study was to work out a method using the Planetary mixer P 600 for the determination of water absorption (WA) and the rheological properties in rye dough made from rye flours of 4 different types (I-IV). In the correlation analysis showed that WA had positive correlation with ash, beginning of gelatinization, $125-160{\mu}m$ particles, sedimentation values at 20 and 25 min, bread yield, pH, and total titratable acidity, but had negative correlation with initial viscosity, gelatinization maximum, viscosities on swelling at 25, 28, and $31^{\circ}C$. The WA determined by the Planetary mixer P 600 agreed well with the experimental baking tests.

• Journal of the Korean Society of Food Science and Nutrition
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• v.28 no.1
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• pp.132-139
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• 1999

Physicochemical properties of the crosslinked potato starches of MDC(Molar Degree of Crosslinking) 0.137~3.333 treated with epichlorohydrin were examined. MDC increased proportionally as epichlorohydrin concentration increased. Water binding capacity increased but blue value decreased with increasing MDC. Gelatinization trends obtained from DSC thermograms and transmittance showed that the gelatinization temperature of the crosslinked potato starch was higher than that of native potato starch, but there was no significant difference among the crosslinked potato starches. Solubility and swelling power decreased with increasing MDC. X ray diffraction patterns and scanning electron micrographs showed that the crosslinking of starch did not affect the crystallinity and the granule shape of starch.

• Applied Biological Chemistry
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• v.36 no.3
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• pp.146-153
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• 1993

The changes in water uptake rate, cooking property, color of rice grain, gelatinization property of milled rice during storage were studied. The water uptake rate constant of milled rice during storage at $4{\sim}30^{\circ}C$ for 3 months decreased, which was more pronounced at elevated storage temperatures. The activation energy of water uptake was different below and above $25^{\circ}C$ of storage temperature. The activation energy after storage for 3 months below and above $25^{\circ}C$ was 608 and 1269 cal/mole, respectively. The rice grain became harder and the cooking time was prolonged by $3{\sim}8$ minutes upon storage. The cooking rate constant was linearly decreased as a function of storage time. The activation energy of cooking after 1 month of storage was 235 cal/mole, which was increased by 1.7 times after storage of 1.5 months and thereafter by 1.2 times with the increase of 0.5 month. There were no significant changes in color of milled rice grains during storage at $4^{\circ}C$, but the increase of b value was observed at higher temperatures. The Initial pasting temperature of rice flour remained essentially unchanged during storage, but the peak viscosity consistently increased with the increase of storage time and temperature. The gelatinization temperature of rice flour by differential scanning calorimetry was not changed but enthalpy of gelatinization was decreased during storage.

• Proceedings of the Korean Society of Crop Science Conference
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• 2005.10b
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• pp.264-265
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• 2005

• Korean Journal of Human Ecology
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• v.1 no.1
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• pp.79-83
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• 1992

Cowpea starch which is the main ingredient of Mook(Korean starch gel) was isolated from cowpea and characterized by physico-chemical methods. Gelatinization properties were investigated by using Brabender amylograph. Starch granules were oval-shape and their size range was $5\;-\;25{\mu}m$. Crystalline type observed by X-ray deffraction was C-type. Apparent amylose content was 20.7%, Amylose and amylopectin fractionated from cowpea starch appeared to have vlue value of 0.55 and 0.089, and ${\beta}-amylolysis$ limit of 79.1 and 71.9%, respectively. Brabender amylograph data showed that initial gelatinization temperature of cowpea starch was $75^{\circ}C$. Also, hot and cooled paste viscosity of 8% starch paste were higher than that of 6% paste by more than twice, breakcown value of two different concentration were almost same. However, in the gelation stage, consistancy and setback of 8% starch paste appeared more than 5 times of those of 6% paste.

• Korean journal of food and cookery science
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• v.30 no.6
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• pp.716-725
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• 2014

Gelatinization properties and the molecular structure of Korean waxy rice starchesisolated from two japonica types, Sinseonchal, and Dongjinchal, as well as an indica type, Hangangchal 1 were investigated. Sinseonchal is preferred cultivar for making Korean traditional rice cakes and cookies. Sinseonchal starch was the highest in crude protein, amylopectin, damaged starch contents, and water binding capacity among the cultivars tested. The initial pasting temperature ($72.75^{\circ}C$), peak (360.54 RVU), breakdown (162.21 RVU) and setback (30.83 RVU) viscosities of Sinseonchal had the highest values (p<0.05). Onset and peak temperatures by differential scanning calorimeter were also the highest in Sinseonchal. The molecular weight of Sinseonchal amylopectin was 5.46 107higher than those of the other cultivars, but its peak height and area were the lowest among them. The amylopectin peak by HPSEC showed a shoulder in the lower molecular weight portion and its relative area decreased in the following order; Sinseonchal > Dongjinchal > Hangangchal 1. On the branch chain length distribution of amylopectin, the proportion of DP13-24 and DP25-36 showed reverse trends, with higher japonica type amylopectin in DP13-24.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.68 no.3
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• pp.99-105
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• 2023

Starch characteristics and pasting properties of Tongil-type rice varieties with different amylose content were analyzed. Three different Tongil-type rice varieties and one Japonica-type rice variety were examined for their properties. Tongil-type rice varieties have longer panicles and higher rice yield (721-765 kg per 10a) than Boramchan, a Japonica-type high-yield rice variety. The protein content of the Tongil-type rice variety was higher than that of Boramchan. Japonica-type rice varieties had lower amylose content than Japonica-type rice varieties, except for Amimyeon (Milyang355). Amimyeon had higher protein content than the other varieties, and its amylose content was particularly high at 39.2%. The distribution of starch granule sizes of the four varieties was similar, and the particle size corresponding to D50 was approximately 87.8-81.9 ㎛. The pasting properties of rice flour varied among varieties. The Dasanbyeo and Hanarum2 amylogram patterns were similar. These two varieties had a higher peak viscosity (PV) and lower setback (SB) than Boramchan. In the case of Amimyeon, the hot paste viscosity (HPV), cool paste viscosity (CPV), and SB were significantly higher than those of the other Toingil-type varieties, and the breakdown (BD) was very low, showing pasting properties significantly different from that of the other varieties. The onset (T_o), peak (T_p), and conclusion temperature (Tc) of gelatinization of rice flour from Amimyeon were lower than those of the other tested varieties. In addition, the gelatinization temperature, measured using differnetial scanning calorimetry (DSC), and BD, measured using al rapid visco analyzer (RVA) were low in Amimyeon. Amylose content showed a high positive correlation with pasting time (PTi), HPV, and SB and a negative correlation with PV and BD.

• Korean journal of food and cookery science
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• v.17 no.1
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• pp.23-28
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• 2001

본 연구는 유색미 가루와 전분의 이화학적 특성 및 호화특성을 알아보기 위하여 수행되었다. 유색미 가루와 전분의 일반성분, 가루의 식이섬유 함량 및 보수력을 분석하였다. 주사전자현미경을 이용하여 가루와 전분의 형태를 관찰하였다. 유색미 전분의 청가 및 아밀로오스 함량을 측정하였고, 가루와 전분의 물결합 능력, 팽윤력과 용해도를 조사하였으며, RVA에 의하여 호화특성을 조사하였다. 유색미 가루의 일반성분은 수분 13.5%, 조단백질 9.1%, 조지방 2.2%, 회분 1.4%, 조섬유 1.3%이었고, 전분의 경우는 수분 13.6%, 조단백질 0.45%, 조지방 0.11%. 회분 0.12%이었다. 백미나 현미에 비하여 단백질의 함량이 매우 높았으며. 조지방과 회분, 조섬유의 함량은 백미에 비하여는 휠씬 높았고, 현미와는 비숫한 수준이었다. 유색미의 식이섬유 함량은 불용성 식이섬유가 3.3% 수용성 식이섬유 2.4%로 총 7.7%였다. 분리된 불용성 식이섬유의 보수력은 약 7.12(g $H_2O$/g NDF)로 매우 물자의 친화력이 큰 편이었다. 주사전자현미경에 의한 관찰결과 가루의 경우는 전분 주위에 단백질 등의 다른 성분들이 있는 것을 볼 수 있었으며, 전분은 다른 쌀 전분과 마찬가지로 불규칙한 다각형의 형태였으며, 크기는 대부분 2-5$\mu\textrm{m}$의 범위로 비교적 균일하였다. 유색미 전분의 청가는 전분이 0.11, 아밀로오스가 0.82. 아밀로펙틴이 0.07이었으며, 아밀로오스 함량은 16.8%이었다. 물결합 능력은 가루가 248%, 전분이 146%이었다. 팽화력과 용해도는 가루와 전분 모두 7$0^{\circ}C$ 이후 증가하였으며 전분이 가루보다 더 급격히 증가하였다. RVA에 의한 호화양상에서 가루와 전분의 호화온도는 각각 85.7$^{\circ}C$와 66.2$^{\circ}C$로 나타났다. 최고점도는 가루가 127.7 RVU, 전분이 243.3 RVU로 차이가 컸으나. setback 후의 점도는 176 RVU과 187.7 RVU로 큰 차이가 없었다. 호화액의 consistency는 가루와 전분이 각각 92와 94로 비슷하였다.

• Fisheries and Aquatic Sciences
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• v.16 no.3
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• pp.143-147
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• 2013

The influence of carrageenan addition on the gelatinization of salt-based surimi gels was investigated by measuring compressive properties and Hunter color scale values. Hydrocolloid kappa (${\kappa}$)-carrageenan at 0%, 0.2%, and 1.0% and NaCl (2% w/w), KCl (1.5% w/w), and a mixture of NaCl (2% w/w) and KCl (1.5% w/w), were added to Alaska pollock surimi. Gel compressive properties were assessed by measuring the breaking force and gel strength. The gelling property of ${\kappa}$-carrageenan-induced surimi gel was significantly increased by the incorporation of KCl rather than NaCl. The addition of ${\kappa}$-carrageenan increased the breaking force and gel strength of surimi gels. Gels with 1% ${\kappa}$-carrageenan and KCl had the highest breaking force and gel strength. The addition of ${\kappa}$-carrageenan caused an increase in the whiteness values of the surimi gels.