Výskumný ústav potravinársky

Sinthukot, M. – Suanjan, S. – Chupawa, P. – Inchuen, S. – Ronsse, F. – Duangkhamchan, W.
Drying characteristics and quality attributes of quick-cooking Job’s tears as affected by rotary drying combined with microwave heating
Journal of Food and Nutrition Research, 63, 2024, č. 1, s. 37-51

Wasan Duangkhamchan, Research Unit of Smart Process Design and Automation, Faculty of Engineering, Mahasarakham University, Kamriang, Kantarawichai, Maha Sarakham 44150, Thailand; Research Unit of Process Design and Automation, Faculty of Engineering, Mahasarakham University, Kamriang, Kantarawichai, Maha Sarakham 44150, Thailand. E-mail: wasan.d@msu.ac.th

Original article
Received 27 June 2023; 1st revised 21 July 2023; 2nd revised 3 August 2023; 3rd revised 19 September 2023; accepted 2 October 2023; published online 2 February 2024.

Súhrn: A combined microwave heating and rotary drying process was developed to prepare the quick-cooking Job‘s tears. Using operating parameters of hot air temperature (70–90 °C), microwave power (150–450 W) and rotational drum speed (0.17–0.50 s^-1), drying characteristics were described using the Page drying model. The model parameters (drying rate constant k and power constant n) considerably correlated with drying factors using the quadratic equation. Drying time (DT) predicted by the Page model and effective diffusivity coefficient (D_e) ranged from 42 min to 116 min and from 487.69 × 10^-8 m²·s^-1 to 1 249.96 × 10^-8 m²·s^-1, respectively. The proposed drying technique resulted in lower DT and higher D_e, while utilizing less energy than hot air drying. Response surface methodology showed the influence of all operating factors on drying rate constant (k), DT, D_e, and specific energy consumption (SEC). Optimal drying conditions were determined by maximizing k and D_e while minimizing DT and SEC as air temperature of 76 °C with 450 W microwave heating and 0.17 s^-1 rotational drum speed. Quality attributes of quick-cooking Job’s tears prepared by drying under such optimal conditions were comparable to those prepared by conventional cooking and freeze-drying. Findings of this study can be used for practical application of Job’s tears grains.

Kľúčové slová: adlay; rotary drying; drying model; microwave heating; quick-cooking grain; response surface

Na stiahnutie:
  jfnr-2024-1-pp037-051-sinthukot.pdf (PDF, 1.55 Mb, 54x)