نوع مقاله : مقاله پژوهشی

نویسندگان

عضو هیئت علمی مؤسسه تحقیقات فنی و مهندسی کشاورزی

چکیده

در برخی مناطق شمالی کشور نظیر استان­های گلستان و مازندران، بالا بودن رطوبت هوا در هنگام برداشت کانولا و انبارمانی آن، باعث بروز فساد و کپک­زدگی این محصول در دورة انبارمانی می­شود.  بنابراین، کاهش رطوبت محصول به حدود مجاز و با اعمال روش­های صحیح برای نگهداری طولانی مدت کانولا، از موارد بسیار مهم و مطلوب به خصوص در مناطق با رطوبت نسبی بالاست.  شرایط خشک­کردن بذر و دانة کانولا بر ظرفیت جوانه­زنی، کیفیت، و مقدار کل روغن اثر به­سزایی دارد، از این رو در این پژوهش، دانه­های واریته ساری­گل (PF 7045/91Brassica napus L., cv.) با دماهای  متفاوت (80، 90، و 120 درجة
سانتی­گراد) برای دانه و (40 ، 45 ، و50 درجة سانتی­گراد) برای بذر، با توجه به رطوبت اولیة دانه­ها در زمان برداشت (12،‌ 15، و 20 درصد) تا رسیدن به رطوبت نهایی حدود 8 درصد خشک شدند.  پس از آن، اثر این تیمارها بر مقدار کل روغن، مقدار اسیدهای چرب آزاد (اسیدیته)، عدد پراکسید، رنگ روغن دانه، و ظرفیت جوانه­زنی بذر خشک­شده بررسی شد.  نتایج نشان داد که استفاده از دمای80 درجة سانتی­گراد با رطوبت اولیة برداشت 12 درصد مناسب­ترین شرایط برای خشک­کردن دانة کانولا با توجه به خصوصیات کیفی روغن، و استفاده از دمای 40 درجة سانتی­گراد با رطوبت اولیة برداشت 12 درصد مناسب­ترین شرایط خشک­کردن برای بذر کانولا با توجه به ظرفیت جوانه­زنی است.

عنوان مقاله [English]

Effect of Harvesting, Moisture Content and Drying Temperature on Canola Oil and Seed Quality

چکیده [English]

Rapeseed is one of the important oilseeds, as its oil ranks second in the world after soybean. The rapeseed cultivation has been increased recently in Iran. Drying of seeds to a safe moisture level is necessary for storage of oilseeds before processing. Rapeseed drying conditions affect the seed quality, total oil and germination capacity. Hence in this research the effects of different temperatures and humidity on the PF variety were studied. Rapeseed samples with different moisture contents at harvesting time (12, 15 and 20% w/w), were dried under 40, 45 and 50ºC temperatures and the rape kernels were dried under 80, 90 and 120ºC temperatures, respectively until reaching final humidity of 8% (w/w).  Then the effect of drying conditions were determined on the total oil, free fatty acid (acidity value), peroxide value, and color of extracted oil and the germination capacity of dried seed.  The result showed that the optimum drying conditions for rapeseed and rape kernel was obtained at 80ºC temperature with 12% moisture content and 40ºC with 12% moisture content (according to the germination capacity), respectively.

کلیدواژه‌ها [English]

  • Canola
  • drying
  • Free fatty acid
  • Germination Capacity
  • Oil
  • quality
  • Rapeseed
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