Evaluation of Mini Bibliometric Analysis, Moisture Ratio, Drying Kinetics, and Effective Moisture Diffusivity in the Drying Process of Clove Leaves using Microwave-Assisted Drying

Microwave-assisted drying (MAD) becomes a drying alternative for faster, high efficiency, and environmentally friendly. Clove plants are promising plantations because can be extracted into high-value essential oils. The purpose of this study was: (i) to evaluate the drying of clove leaves with MAD using six mathematical models, (ii) to investigate the effect of microwave power parameters and leaf size on clove leaf drying, and (iii) bibliometric analysis was used to prove the novelty of the study. Fresh clove leaves are grouped into large leaves (15.28 +/- 1.33 cm x 5.12 +/- 0.19 cm) and small leaves (14.00 +/- 1.36 cm x 4.09 +/- 0.39 cm) then dried with 4 different microwave powers namely 136, 264, 440, and 616 W. Six mathematical models (Page model, Verma model, Logarithmic model, Two-term Exponential model, Henderson and Pabis model, and Midilli model) were used to estimate the drying coefficient by following the non-linear regression method. The results showed that the Midilli model became the most accurate model to show the drying characteristics of clove leaves compared to 5 other confirmed mathematical models with SSE values ranging from 0.0001 -0.0034. The k value of the Midilli model parameter indicates the MAD condition of the clove leaf with values ranging from 0.0002 -0.0097. The De value indicates the moisture dispersal ability of the clove leaf with values that tend to fluctuate, namely around 4.6 x 10 - 12- 9.9 x 10- 11 m 2 /s.