Acceleration of turmeric drying using convection and microwave‐assisted drying technique: An optimization approach

Abstract

The aim of this study was to optimize the drying process of turmeric using convection drying followed by microwave drying to accelerate the drying time. Convection time (0-30 min) and microwave time (20-60 min) were the two investigation factors. The obtained dried turmeric was pulverized. Water, volatile oil, and curcuminoid contents were determined. Weight loss after drying was also investigated. Results showed that increasing the convection time and microwave time increased weight loss and decreased water content. Microwave time had a significant effect on water, volatile oil, and curcuminoid contents, while convection time did not. The highest content of volatile oil and curcuminoids, and the lowest content of water were found when microwave drying was carried out for approximately one hour without convection drying. In summary, the optimization of the drying process could accelerate the drying time and turmeric that met the standards of Thai Herbal Pharmacopoeia. Practical applicationsThe optimization data could be used as a guide for the selection of drying condition for turmeric raw materials to meet the standards of the Thai Herbal Pharmacopoeia.

Curcuma longa L. Rhizome Essential Oil from Extraction to Its Agri-Food Applications. A Review

“…A different trend was observed by Gounder et al, who reported the higher activity of cured (fresh rhizome boiled in water, dried in shade and polished) and dried rhizome oils over fresh ones [ 165 ], probably due to the lower percentage of ar-turmerone and β-turmerone. Anyway, the control of the drying conditions constitutes an important parameter in order to obtain the highest content of essential oil in the minimum time possible [ 166 , 167 ]. The sun and mechanical drying coexist as drying methods of C. longa rhizomes [ 156 ].…”

“…The sun and mechanical drying coexist as drying methods of C. longa rhizomes [ 156 ]. In particular, Monton et al confirmed that one hour of microwave drying without conventional drying represented the optimum conditions to obtain the highest content of turmeric essential oil [ 167 ].…”

Microwave assisted drying and extraction technique; kinetic modelling, energy consumption and influence on antioxidant compounds of fenugreek leaves

“…Therefore, an emerging drying technique with the purpose of making process of dehydration more sustainable is needed. Microwave based technique (Ali et al, 2020;Khan et al, 2016;Monton et al, 2019a) has exhibited its potential for drying i.e. reduced drying time and cost.…”

Investigation of the Interaction of Herbal Ingredients Contained in Triphala Recipe Using Simplex Lattice Design: Chemical Analysis Point of View

“…They indicated that the data distribution was within 95% confident interval. It could be confirmed that the prediction by Design-Expert® software was stable [32][33][34][35][36]. Figure 7(a) shows that contour plots of the desirability of the optimal condition provided the simultaneous minimizing CI of the extraction yield and total content of the four phenolic compounds.…”

“…They indicated that the data distribution was within 95% confident interval. It could be confirmed that the prediction by Design-Expert® software was stable [ 32 – 36 ].…”