The drying kinetics of pullulan and pullulan-PEG film forming solutions were investigated. The results were as followed: the drying curves of pullulan-based films were divided into three stages: the rising rate, the falling rate, and the constant rate period; four mathematical models were fitted to the experimental data; among the drying models considered, the Wang and singh model was found to satisfactorily describe the drying kinetics of pullulan solutions. However, Modified Page equation-II model was found to satisfactorily describe the drying kinetics of pullulan-PEG solutions. As the drying temperature increased from 40 ℃ to 70 ℃, the effective moisture diffusion coefficient (Deff) of pullulan and pullulan-PEG samples increased from 0.019 6×10-11 m/s2 to 0.255 7×10-11 m/s2, and from 2.400×10-11 m/s2 to 11.388×10-11 m/s2, respectively. As the drying temperature increased, Deff of pullulan based film forming solutions increased, whereas the Deff of pure pullulan samples was lower than that of pullulan-PEG. Moreover, drying activation energy of pullulan and pullulan-PEG blend samples was 9 114.8 kJ/mol, and 2 475.2 kJ/mol, respectively.
Yujia, ZHOU; Qian, XIAO; Xingchi, LU; and Fangming, DENG
"Drying kinetics of pullulan-based film forming solutions,"
Food and Machinery: Vol. 31:
6, Article 3.
Available at: https://www.ifoodmm.cn/journal/vol31/iss6/3
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