Comparing hot air drying kinetics and color quality of organic and conventional sweet red peppers

Year 2020, Volume: 25 Issue: 2, 271 - 283, 21.08.2020

Aysel Arslan Yurtsever Soysal Muharrem Keskin

https://doi.org/10.37908/mkutbd.747675

Cited By: 1

Abstract

Aims: This study was conducted to compare the hot air drying kinetics and color quality of organically and conventionally produced sweet red peppers.
Methods and Results: The pepper samples were dried at 60, 70 and 80°C using a hot air dryer. Drying kinetics, effective moisture diffusivity (Deff), activation energy (Ea) and color quality were studied. The drying process for both organic (OSRP) and conventional sweet red peppers (CSRP) occurred mainly in falling rate period. Increasing the drying temperature reduced the drying time considerably. Except 60°C, significant difference was found between the drying times of OSRP and CSRP samples. The Midilli model gave the best fit for all data points for pepper types. A positive relationship was found between the drying temperature and Deff values (OSRP: 39.6210-10 – 58.5810-10 m2s-1; CSRP: 38.9210-10 – 57.5910-10 m2s- 1). Differences between the Deff values of OSRP and CSRP samples were not significant.
Conclusions: Characteristic drying curve profiles, Deff and Ea values followed the similar trajectory showing that the growing practice of the peppers did not significantly change the structural features related to heat transfer. The hot-air drying at 70°C and 80°C gave brighter and redder pepper powders; hence, these treatments are suggested as the suitable drying applications to produce high quality OSRP and CSRP powders in terms of color quality. By using 80°C instead of 60°C, about 25% and 32% savings in drying times could be obtainable for CSRP and OSRP samples, respectively.
Significance and Impact of the Study: Organic production has an increasing trend in the world; however, research on the evaluation of drying kinetics and color quality of organic products is very limited. Thus, this study aimed at studying appraisal of the drying kinetics and related parameters of CSRP and OSRP samples.

Keywords

Organic red pepper, hot-air drying kinetics, modeling, moisture diffusivity, activation energy, color

Thanks

The authors would like to thank Dr. Yunus Emre Sekerli for his assistance during the experiments.

Organik ve konvansiyonel tatlı kırmızı biberlerin sıcak hava kurutma kinetiği ve renk kalitesinin karşılaştırılması

Abstract

Amaç: Bu çalışma organik ve konvansiyonel olarak üretilen tatlı kırmızı biberlerin sıcak hava kurutma kinetiklerini ve renk kalitesini karşılaştırmak için yapılmıştır.
Yöntemler ve Bulgular: Biber örnekleri, sıcak hava kurutucuda 60, 70 ve 80°C’de kurutuldu. Kurutma kinetiği, efektif nem difüzyonu (Deff), aktivasyon enerjisi (Ea) ve renk kalitesi incelenmiştir. Hem organik (OTKB) hem de konvansiyonel tatlı kırmızı biberler (KTKB) için kurutma işlemi temel olarak azalan hızlı kurutma periyodunda gerçekleşmiştir. Kurutma sıcaklığının arttırılması, kuruma süresini önemli ölçüde azaltmıştır. 60°C haricinde, OTKB ve KTKB örneklerinin kuruma süreleri arasında önemli bir fark bulunmuştur. Midilli modelinin biber tipleri için tüm veri noktalarına en uygun verileri sağladığı tespit edilmiştir. Kurutma sıcaklığı ve Deff değerleri arasında (OTKB için 39.62x10-10 - 58.58x10-10 m2s-1 ve KTKB için 38.92x10-10 - 57.59x10-10 m2s-1) pozitif bir ilişki bulunmuştur. Deff değerleri bakımından OTKB ve KTKB arasında dikkate değer bir fark bulunmamıştır.
Genel Yorum: Karakteristik sıcak hava kurutma eğrisi profilleri, Deff ve Ea değerlerinin OTKB ve KTKB için benzer eğilimi izlediği ve kırmızı biberin yetiştirilme yönteminin ısı transferi ile ilgili yapısal özelliklerini önemli ölçüde değiştirmediği görülmüştür. 70°C ve 80°C'de sıcak hava ile kurutma, daha parlak ve daha kırmızı biber tozları sağladığından bu uygulamalar renk kalitesi açısından yüksek kaliteli OTKB ve KTKB tozları üretmek için uygun kurutma uygulamaları olarak önerilmektedir. 60°C yerine 80°C kullanılarak KTKB ve OTKB örnekleri için kurutma sürelerinde yaklaşık %25 ve%32 tasarruf sağlanabilmektedir.
Çalışmanın Önemi ve Etkisi: Organik üretim dünyada giderek artan bir eğilime sahiptir; ancak organik ürünlerin kurutma kinetikleri ve renk kalitesi ile ilgili araştırmalar çok sınırlıdır. Bu nedenle, bu çalışmada OTKB ve KTKB örneklerinin kurutma kinetiği ve ilgili parametreleri değerlendirilmiştir.

Keywords

Organik kırmızı biber, sıcak hava kurutma kinetiği, modelleme, nem difüzyonu, aktivasyon enerjisi, renk

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