Hot Air Drying Characteristics and Shrinkage Dynamics Model of Potato Chips

In order to improve the drying efficiency and quality of potato chips, and to control the shrinkage deformation during hot air drying, the effects of temperature (45, 55, 65, 75 ℃) and slice thickness (3, 5, 7, 9 mm) on the drying characteristic curve, effective moisture diffusivity and activation energy of potato chips were studied. The results showed that the drying rate would increase with the increase of the hot air temperature or the decrease of the slice thickness of potato chips. Within the scope of the study, the effective moisture diffusivity of potato chips was between the range of 5.02×10−10~11.53×10−10 m2/s. And its value would increase with the increase of the hot air temperature and/or the decrease of slice thickness. Besides, it was found that the Weibull distribution function could describe the reduction rate stage of drying and shrinkage dynamics model of potato chips. According to Arrhenius equation, the activation energy of drying and shrinkage of potato slices were 27.35 and 46.44 kJ/mol, respectively, indicating that the activation energy of drying was less than that of shrinkage of potato slices. This work provided theoretical basis and technical support for the prediction of moisture transfer and shrinkage deformation of potato chips during hot air drying.