تعیین شرایط بهینه خشک کردن دانه انار در خشک‌کن خورشیدی

نوع مقاله: مقاله پژوهشی

نویسندگان

1 عضو هیات علمی مرکز تحقیقات کشاورزی و منابع طبیعی استان فارس

2 دانشیار بخش ماشین آلات دانشکده کشاورزی دانشگاه شیراز

3 استادیار پژوهشی مرکز تحقیقات کشاورزی و منابع طبیعی استان فارس

4 مربی پژوهشی مرکز تحقیقات کشاورزی و منابع طبیعی استان فارس

چکیده

هدف از اجرای این پروژه تعیین شرایط بهینة خشک کردن دانة انار با خشک‌کن خورشیدی است.  در این تحقیق از یک خشک‌کن خورشیدی کابینتی به صورت فعال و مختلط استفاده شد.  تیمارها با استفاده از روش سطح پاسخ در 9 حالت مختلف در نظر گرفته شدند که تیمار مرکزی (3 متر‌بر‌ثانیه سرعت جریان هواو 2 سانتی‌متر ضخامت) 5 بار تکرار شد.  در این تحقیق از دانه‌های انار رقم بریت استفاده شد و نمونه‌ها تا رسیدن رطوبت آنها به تقریبا 10 درصد خشک شدند.  مدت زمان خشک شدن، ویتامین ث، رنگ، اسیدیته، و وضعیت میکروبی نمونه‌ها بررسی شد.  اثر ضخامت محصول و سرعت عبور هوا بر زمان خشک شدن، و دیگر عامل‌های کیفی ذکر شده، به جز اسیدیته و طعم، معنی‌دار بود(05/0p<).  افزایش سرعت عبور هوا و ضخامت محصول موجب شد که زمان خشک شدن، زردی محصول (عاملb رنگ)، و کپک و مخمر افزایش اما روشنی (عاملL رنگ)، قرمزی (عامل  aرنگ)، و ویتأمین ث، کاهش یابد.  همچنین مشخص شد که محصول تولید شده در روش خورشیدی کیفیت بالاتری نسبت به محصول تولید شده در روش آفتابی دارد.  ضخامت 6/0 سانتی‌متر و سرعت جریان هوای 3متر‌بر‌ثانیه در خشک‌کن خورشیدی بهترین کیفیت و کمترین زمان خشک شدن را نشان دادند.  زمان خشک شدن نمونه‌ها در این شرایط نسبت به زمان خشک شدن در روش آفتابی 85 درصد کاهش یافت.

کلیدواژه‌ها


عنوان مقاله [English]

Optimum Conditions for Drying Pomegranate Arils in a Solar Dryer Using Surface Response Method

چکیده [English]

This study determined optimum conditions for drying pomegranate arils in a solar dryer. A cabinet solar dryer was used in active and mixed modes. The response surface method was employed with nine treatments (runs) and a control run (3 m/s air velocity and 2 cm in thickness) and five replications. The Bryte cultivar was tested and samples were dried to approximately 10% moisture. Drying time, vitamin C, color, acidity, and microorganisms were evaluated in the samples. The effects of thickness and air velocity on drying time and all qualitative factors were significant except for acidity and taste (p < 0.05). Drying time, yellowness (b factor in color) and microorganisms increased as thickness and air velocity increased. Brightness (L factor in color), redness (a factor in color), and vitamin C decreased with as thickness and air velocity increased. The quality of the dried products in the solar dryer was much better compared to the sun-dried control samples. Samples 0.6 cm in thickness with 3 m/s air velocity had the best quality in the solar dryer. Their drying time decreased 85% in comparison with sun drying.

کلیدواژه‌ها [English]

  • Pomegranate seeds
  • Response surface method
  • solar dryer
  • Sun drying
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