도정효율 증진을 위한 벼 품종특성별 현미선별체 적정크기

Optimum Sieve-slit width for Effective Removal of Immature Kernels based on Varietal Characteristics of Rice to Improve Milling Efficiency

  • 이춘기 (농촌진흥청 국립식량과학원) ;
  • 김정태 (농촌진흥청 국립식량과학원) ;
  • 최윤희 (농촌진흥청 국립농업과학원) ;
  • 이재은 (농촌진흥청 국립식량과학원) ;
  • 서종호 (농촌진흥청 국립식량과학원) ;
  • 김미정 (농촌진흥청 국립식량과학원) ;
  • 정응기 (농촌진흥청 연구정책국) ;
  • 김정곤 (농촌진흥청 국립식량과학원)
  • 발행 : 2009.12.31

초록

본 연구는 립선별기에서 미숙립 선별능력을 높임으로써 도정효율 증진과 완전미율 향상을 꾀하고자 품종특성을 고려한 립선별기 선별체 최적 조건 구명 시험이 수행되었고, 다음과 같은 결과가 얻어졌다. 1. 립선별기의 선별능력은 현미립 두께에 절대적으로 의존되었는데, 조사된 시험재료의 현미 평균 두께는 1.79(농안)-2.16 mm(대립벼1호)의 분포를 보였다. 2. 품종별 차이는 있었으나, 대체적으로 현미의 평균 립두께가 2.08 mm이상일 경우 1.9 mm 선별체, 2.00-2.08 mm 범위일 경우 1.8 mm 선별체, 1.90-2.00 mm 범위일 경우 1.7mm 선별체, 그 이하일 경우 1.7 mm 이하의 선별체가 정립 손실을 최소화하면서(0.1%이내) 완전미율을 향상시킬 수 있는 조건인 것으로 판단되었다. 3. 백미 품위에 미치는 선별체 분리효과는 미숙립 비율이 높은 품종일수록 크게 발휘되었다. 4. 현미선별 체 눈 크기를 0.1 mm씩 증가시킬 경우 품종별로 현미선벌체 통과물중에 정상립이 포함되어 발생되는 정상립 손실율이 0.5% 수준까지는 현미선별체 눈금크기 증가에 따라 미미하게 증가하였으나, 이 눈금 수준이상에서는 선별체 눈금 0.1 mm 증가에 따라 정상립의 손실율이 급격히 증가하는 것으로 보아 정상립 손실율 0.5% 수준의 눈금이나 그 보다 0.05~0.10 mm 아래 눈금의 선별체가 적당할 것으로 생각되었다.

On the purpose to improve the milling efficiency as well as head-rice percentage after milling, an experiment to improve the removal ability of immature kernels in the immature brown rice separator (IBRS) was performed focused on varietal characteristics. The removal ability of immature grains by the IBRS was absolutely depending on kernel thickness of brown rice. The kernel thickness of the tested rice varieties distributed from 1.79 mm in Nonganbyeo to 2.16 mm in Daeribbyeo 1. Although there were some variation among rice varieties, it was roughly suggested that the suitable sieve-slit widths for good separation of the immature kernels were 1.9 mm for the varieties thicker than 2.08 mm in thickness, 1.8 mm for the varieties with 2.00-2.08 mm thickness, 1.7 mm for the varieties with 1.90-2.00 mm thickness, and 1.60-1.65 mm for the varieties thinner than 1.7 mm. It was found out that the higher the proportions of immature kernels in brown rice, the more conspicuous the improvement of milling efficiency as well as head rice rates by their removals. With increasing the sieve slit-widths beyond an optimum range, the losses of mature grains increased sharply. For effective separation of immature kernels, it was suggested that the optimum sieve-slit width should be set up depending on both of the kernel thickness and the critical loss limit of mature kernel.

키워드

참고문헌

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