Thermal, structure, and rheological properties of native potato flour prepared under different combined drying methods

Abstract

Native potato flour is one of the functional additives for dough making in food processing to meet the increasing healthy food requirements. To explore an efficient combination drying methods for native potato flour processing, different drying treatments including hot air (AD), freeze-drying (FD) and radio frequency (RFD) were introduced and investigated in this study. The associated color, thermal, pasting, crystalline, rheological, and morphological properties of the potato flour were investigated and evaluated systematically. The gelatinization temperature of potato flour increased from 63.73 to 69.47 °C with drying temperature increased, which indicated the thermal stability of the flour can be strengthened by drying temperature. The gelatinization enthalpy, viscosity, and relative crystallinity of the dried potato flours decreased as the treatment temperature increase, which indicated the extension of thermal denature as the effect of increasing drying temperature. It is worth to note that the RFD combined method has the most efficient drying rate and moderate heat damage. Therefore, combined drying methods are meaningful for native potato flour processing, which might be valuable for industrial development.

Keywords:

• Potato flour
• combined drying
• gelatinization
• properties
• rheology

Acknowledgment

The authors thank Dr. Lan Yang (Analytical & Testing Center, Southwest University, Chongqing, China) for her technical support.

Additional information

Funding

This research was supported by The National Key Research and Development Program of China (2018YFD0700200, 2016YFD0401300). Fundamental Research Funds for the Central Universities (Grant No. SWU119068).