Studies on the suitable temperature for rice drying

미곡의 건조 적정 온도에 관한 연구

  • Lee, B.Y. (Agriculture Sciences Institute, Rural Development Administration) ;
  • Son, J.R. (Agriculture Sciences Institute, Rural Development Administration) ;
  • Kim, Y.B. (Agriculture Sciences Institute, Rural Development Administration) ;
  • Yoon, I.H. (Agriculture Sciences Institute, Rural Development Administration)
  • 이병영 (농촌진흥청 농업기술연구소) ;
  • 손종록 (농촌진흥청 농업기술연구소) ;
  • 김영배 (농촌진흥청 농업기술연구소) ;
  • 윤인화 (농촌진흥청 농업기술연구소)
  • Published : 1991.09.30

Abstract

In order to establish the optimum drying temperature of the heated air blast-grain circulation dryer, a 2 ton scale of paddy was used in this experiment. The temperatures of heated air used were 45, 50, 55, 60, 65 and $70^{\circ}C$. Moisture content of the paddy was reduced to 15% from 24% by drying. The higher air temperature, the shorter drying time and the less fuel consumed. The portion of cracked kernels was found to be low as $3{\sim}10%\;at\;40{\sim}55^{\circ}C$, but was very high to $28{\sim}30%\;at\;60{\sim}70^{\circ}C$. The germination percent was very high as 98 and 93% at 40 and $45^{\circ}C$, but it was decreased to 86 and 30% at 50 and $70^{\circ}C$, respectively. The recovery yield of milled rice from paddy was decreased by 1.76, 2.63 and 7.52% at 60, 65 and $70^{\circ}C$, respectively, compared with 75.86% as drying at $40^{\circ}C$. The higher heated air temperature, the less head rice of milled rice was recovered, and the decreased ratio was increased $60^{\circ}C$. The higher heated air temperature, the less alkali disintergation value and gel consistency of milled rice and the more water up take, expanded vlume, total solid in residual liquid and intensity of starch iodine blue value of residual liquid, and those tendency was found clear from $60^{\circ}C$ temperature of heated air.

순환식 곡물건조기의 열풍온도별 미질특성을 구명하여 건조적정온도를 확립하기 위하여 2톤 규모의 순환식 열풍건조기를 이용 열풍건조온도를 $40^{\circ}C$에서 $70^{\circ}C$까지 $5^{\circ}C$간격으로 하여 수분함량 24%에서 15%까지 건조하는데 건조효율 및 건조벼의 미질 특성을 조사하였던바 열풍건조 온도별 소요된 건조일수는 온도가 높을수록 짧았고 석유소요량은 적었다. 동할립은 $40{\sim}55^{\circ}C$로 건조하였을 때 $3{\sim}10^{\circ}C$였으나 $55^{\circ}C$에서 $70^{\circ}C$까지 건조하였을 땐 $19{\sim}30%$로 매우 높았으며, 발아율은 40 및 $45^{\circ}C$으로 건조하였을 때 각각 98 및 93%였으나 $50^{\circ}C$로 건조하였을 때 86%로 감소하였으며, $70^{\circ}C$로 건조하였을 때는 30%밖에 안되었다. 도정율은 $40^{\circ}C$의 75.86%보다 60, 65 및 $70^{\circ}C$에서 각각 1.76, 2.63 및 7.52% 감소하였다. 또한 백미의 완전립율도 건조온도가 높아짐에 따라 감소하였는데 $60^{\circ}C$에서부터 감소폭이 급증하는 경향이었다. 알카리 붕괴도 및 호화응집성은 건조 온도가 높아짐에 따라 낮아졌으며 $60^{\circ}C$에서 그 폭이 컸다. 취반미는 흡수율, 용적팽창율, 취반용액중의 용출고형물 및 요드 정색도가 증가하였는데 일반적으로 $60^{\circ}C$에서 증가 폭이 컸다.

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