Influence of pre-treatment on the drying process of apricots

Document Type: Full Article


Department of Biosystems Engineering, Faculty of Agriculture, Shahid Bahonar University of Kerman, Kerman, I. R. Iran


ABSTRACT- Drying has been used for the preservation of fruits since ancient times. Dried apricot reduces the damages, weight and volume losses, packaging space, storage and handling costs. In this paper, the effects of hot air dryer on an Iranian apricot cultivar ”Noori” have been investigated. The experiment was conducted at three temperatures (30, 40 and 50oC), three fruit thicknesses (5, 10 and 15 mm) and two pre-treatments (sulphur dioxide and water soluble sodium meta-bisulphite (Na2S2O5)). Based on the analysis of variance, the effects of temperature, thickness, pre-treatment and their interactions on drying time were significant (P<1%). It was revealed that water soluble  reduced drying time more than sulphur dioxide. The data was fitted to eight different mathematical models. Page model was determined as the best one to explain thin layer drying of apricots by comparing the coefficient of correlation determination(R), chi-square ( ) and root mean square error (RMSE) between the observed and expected moisture ratios.


Article Title [Persian]

بررسی اثر پیش‌تیمار بر فرایند خشک کردن زردآلو

Authors [Persian]

  • کاظم جعفری نعیمی
  • راضیه احمدی
  • محمود داوری شمس آبادی
بخش مهندسی مکانیک بیوسیستم، دانشکده کشاورزی، دانشگاه شهید باهنرکرمان، کرمان، ج. ا. ایران.
Abstract [Persian]

چکیده- از دیرباز از خشک کردن برای نگهداری میوه ها استفاده می شده است. زردآلوی خشک خسارت، وزن و حجم تلفات، فضای بسته بندی، انبار داری و هزینه های حمل و نقل را کاهش می دهد. در این تحقیق، اثرات خشک کن هوای داغ بر میوه زردآلوی ایرانی رقم نوری، تجزیه و تحلیل شده است. این آزمایش در سه درجه حرارت (30، 40 و 50درجه سلسیوس)، سه ضخامت (5، 10 و 15 میلی متر) و دو پیش تیمار (دی اکسید گوگرد و  متا بی سولفیت سدیم محلول در آب) انجام شد. بر اساس تجزیه و تحلیل واریانس، اثرات دما، ضخامت، پیش تیمار و اثر متقابل این عوامل بر زمان خشک شدن محصول در سطح 1٪ معنی دار بودند. مشخص شد که محلول متا بی سولفیت سدیم زمان خشک کردن را بیش از دی اکسید گوگرد کاهش می دهد. داده ها در هشت مدل مختلف ریاضی برازش داده شدند. مدل پیج به عنوان بهترین مدل برای توصیف خشک کردن لایه نازک زردآلو، با مقایسه تعیین ضریب همبستگی (R2)، مجذور کای ( ) و ریشه میانگین مربع خطا (RMSE) بین نسبت رطوبت مشاهده شده و مقدار مورد انتظار آن، مشخص شد.

Keywords [Persian]

  • واژه های کلیدی:
  • مدل‌سازی ریاضی
  • سینتیک خشک شدن
  • مدل پیج
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