• 한국식품조리과학회지
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• 제23권6호
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• pp.908-918
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• 2007

To prepare ready-to-use rice flour as de novo material for processed rice foods, glutinous(W) and normal rice grains (N) were soaked for 1, 8, and 12 hours prior to processing. One half (DG) was air-dried and milled, and the other (WG) was milled and air-dried. General, morphological and pasting properties of the flours (NDG, NWG, WDG, WWG) were compared to those of a control (raw milled rice without soaking). The general compositions of the rice flours varied with soaking. Crude ash was considerably decreased at the beginning of soaking (1 hour). With the soaking, the rice flour, having polygonal shaped particles and a layered surface, acquired particles with smooth edges, which were then uniformly distributed. Additionally, the WG flour was lighter and had a lower ${\Delta}E$ value than the DG flour, due to a higher L and less +b as a result of soaking. Compared to the control, the WBC of the normal rice flour was decreased significantly with soaking, and the WG flour had significantly lower WBCs than the DG flour. Stirring number (SN), an indicator of ${\alpha}-amylase$ activity, was highly and significantly correlated with WBC (r=-0.85, p=0.0001) in the normal rice flour. At $80^{\circ}C$, the SP and solubility of all the soaked rice flours were much higher than those of the control. Positive (r=+0.85, p=0.0001) and negative (r=-0.61, p=0.02) correlations between the SP and solubility of the normal and glutinous rice flours were found, respectively. Using RVA, the pasting temperature of NDG was lower than that of NWG (p<0.0001). The peak viscosities of all the soaked flours were significantly decreased with soaking (p<0.0l), with the highest viscosity in the normal rice flour soaked for 8 hrs. Total setback, indicative of retrogradation, was lower in NDG than in NWG, with the lowest setback at 8 hrs of' soaking. Based on these finding, the NDG flour with 8 hrs of soaking was less damaged, and had a lower total setback and lower pasting temperature, which would make it an appropriate rice flour for commercial mass production.

• 한국식품조리과학회지
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• 제22권2호
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• pp.147-157
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• 2006

멥쌀가루의 특성을 개선하여 제빵을 비롯한 가공 적성을 증가하기 위해 습식제분쌀가루를 이용하여 수분함량을 30%와 50%로 조절하고, 50과 $70^{\circ}C$로 6시간과 18시간 열처리하여 수분-열처리 쌀가루를 제조하였다. 제조한 수분-열처리 쌀가루의 특성인 입도분포, 형태적, 이화학적특성과 호화특성을 건식제분과 습식제분 쌀가루와 비교하였다. 30% 수분함량으로 처리한 쌀가루입자는 습식제분쌀가루와 같이 $4-20{\mu}m$와 $100-200{\mu}m$ 범위에 분포하였으며 열처리온도가 증가하면 $200{\mu}m$이상의 입자가 형성되었다. 주사전자현미경으로 형태를 보면 30% 수분으로 처리한 경우에는 전분입자를 뚜렷하게 볼 수 있었으나 50%로 처리한 쌀가루는 쌀가루 입자끼리 엉겨 붙거나 호화된 상태를 보여주었다. 색도는 수분함량과 열처리온도가 높은 경우 명도는 감소하고 황색도는 증가하였으며 30% 수분함량으로 처리한 쌀가루의 물결합능력은 SWRF와 비슷하였다. $70^{\circ}C$에서 쌀가루의 팽윤력은 수분함량에 따른 차이는 없었으며 같은 수분함량에서 열처리 온도가 낮은 $50^{\circ}C$일 때 더 높았고 용해도는 더 낮았다. 신속점도 측정기에 의한 호화개시온도는 수분-열처리로 모두 높아졌으며 최고점도는 30%로 처리한 쌀가루가 높았고 setback은 30%로 $50^{\circ}C$에서 처리하였을 때 낮아 노화에 안정성을 보였다. 그러므로 수분함량을 30%로 조절하고 호화온도 이하의 온도인 $50^{\circ}C$로 처리한 수분-열처리 쌀가루의 특성이 쌀가루의 가공용으로 습식제분쌀가루보다 개선된 것으로 생각되었다.

• 한국작물학회:학술대회논문집
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• 한국작물학회 2017년도 9th Asian Crop Science Association conference
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• pp.276-276
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• 2017

This study was examined to establish a conditions for producing Tteokbokki using dry-milling rice flour which can save manpower and labor time. Since the cost of producing rice flour milled in a wet condition is 500 to 700 won/kg, which is more than twice as much as that of 300 won wheat flour, it is necessary to directly make rice flour from raw rice. The dry-milling rice flour used in the experiment was produced by Air mill (Nara machinary co. ltd., Tokyo, Japan) from 5 rice cultivars (Samkwang, Dasan-1, Boramchan, Seolgaeng, Hanareum-2), which were cultivated in A-san in 2015 year. Their particle sizes were 50, 100 and $150{\mu}m$ for each cultivar, respectively. A control was a wet-milled rice flour milled with a roll mill after the rice was soaked in water for 4 hours. The moisture content of dry-milling rice flour based on cultivars was 11 ~ 12%, and added water up to 50~55% of dry-milling rice flour weight. The RVA characteristic of peak viscosity was the highest in Dasan-1 and Hanareum-2, the lowest in Seolgaeng. The setback value used as an indicator of aging was the highest in Dasan-1, therefore Dasan-1 was expected to be quick solidification, resulting in the low tendency of sensory evaluation. The damaged starch was high in Dasan-1 and Boramchan (p<0.05) compared to others. The Hunter color L were no significant among cultivars and b value increased in all cultivars of dry-milling rice flour compared with control. The hardness of dry-milling rice flour was higher than that of the control, especially Dasan-1 and Hanareum-2 were the highest. Based on the sensory evaluation, the best cultivars were Boramchan, Hanareum-2 and Samkwang. The overall preference of dry-milling rice flour was good in particle size of 50~100um.