Hot air convective dehydration characteristics of Daucus carota var. Nantes

Raees-Ul Haq,Kamlesh Prasad,Pradyuman Kumar,Fatih Yildiz

doi:10.1080/23311932.2015.1096184

Abstract

AbstractThe present work focuses on experimental and theoretical study of air dehydration kinetics of Daucus carota var. Nantes in laboratory scale drying chamber. Steam blanching as a pretreatment was applied prior to dehydration of shreds and the results indicated a gradual decrease in drying time from 2.9 to 5.5% in temperature range of 50–70°C, for steam blanched samples in comparison to untreated carrots. Four different mathematical drying models (Newton, Page, Modified Page and Henderson and Pabis) were evaluated for goodness of fit by comparing their respective R2, χ2, and RMSE parameters. Comparison of the statistical parameters led to conclusion that Page model showed a better quality of fit and presents dehydration characteristics in better way to obtain drying curves than any other model.

Highlights

Carrot (Daucus carota) is important crops of Apiaceae family along with other prominent members of the family include fennel, coriander, parsley, and so on (Cherng, Chiang, & Chiang, 2008)
Increase in dehydration temperature decreases the dehydration time in both cases with blanches shreds showing a little bit decrease in dehydration time as compared to its untreated form. Reason for this type of behavior is attributed to blanching that softens the tissue and enhances water diffusion rates from the solid sample (Doymaz, 2008; Górnicki & Kaleta, 2007). In both blanched and unblanched carrot shreds drying at higher temperature (70°C) resulted in decrease of time by over 50% or more accurately 53 and 54%, respectively, for former and later
Drying process occurred during the falling rate period during which higher temperatures resulted in reduction of moisture levels to a greater extent that can be correlated to elevated temperatures causing more heat and mass transfer (Aghbashlo, Kianmehr, Arabhosseini, & Nazghelichi, 2011)

Summary

Introduction

Carrot (Daucus carota) is important crops of Apiaceae family along with other prominent members of the family include fennel, coriander, parsley, and so on (Cherng, Chiang, & Chiang, 2008). Carrots are among rich and popular sources of carotenoids and phenolics with appreciable amounts of minerals. Carrot is the unique root crop that shows the presence of pro vitamin A substances and is grown mainly in temperate regions of the world (RodriguezAmaya, 2001). Carrot roots show a greater diversity in root color ranging from ancient black to modern yellow that are used for the development of different food products (Haq & Prasad, 2015). Nantes form of carrot has tapered yellow colored roots popular throughout the world than any other colored root form. These roots have harder crispier texture and richer amounts of bioactive components that make them popular throughout the world (Kaszab, Csima, Lambert-Meretei, & Fekete, 2002)

Methods

Results

Conclusion