**4. Conclusions**

Potato is an important raw food material, but the limited storage and transportation of fresh potato lead to fewer types of processed products, while after drying and milling, potato can retain most of the nutrients, is easy to use, has stable storage and can provide special tastes and aromas. Compared with potato starch, potato flour has more comprehensive nutrition and superior processing performance and is an important raw material for staple potato food products. The variation in physicochemical properties, including viscosity, X-ray diffraction and volatile compositions, of HAD potato flour were observed using enzyme hydrolysis, rapid visco analyzer, X-ray diffractometer and headspace solid-phase microextraction coupled with gas chromatography-mass spectrometry (HS-SPME GC-MS). The results indicate that HAD temperature is an important index affecting the quality of potato powder. Higher temperatures lead to an increase in DG value, a decrease in peak viscosity, poor gel ability and aging, the destruction of the crystal structure and the loss of bad flavor and key flavors of potato powder. However, low-temperature HAD for a long time will also reduce the viscosity stability; HAD-60 has more comprehensive nutrition and flavor and better processability. The results provide more detailed data for the raw material processing technology of staple potato foods and can effectively guide the process optimization and quality classification of potato flour. However, there are other ways to process potato flour, such as infrared drying, microwave drying, etc. The influence of different drying methods needs to be further analyzed in future research.

**Author Contributions:** Methodology, J.B.; software, R.Z.; validation, J.H.A.; formal analysis, S.L.; investigation, K.W.; resources, J.B.; data curation, X.T.; writing—original draft preparation, X.T.; writing—review and editing, J.B.; visualization, H.Z.; supervision, J.B.; project administration, H.Z.; funding acquisition, H.Z. All authors have read and agreed to the published version of the manuscript.

**Funding:** This research was funded by Shanghai Municipal Human Resources and Social Security Bureau, Shanghai Pujiang Program, gran<sup>t</sup> number 2021PJD021; Shanghai Urban Construction Vocational College, Key Scientific Research Project of Shanghai Urban Construction Vocational College, gran<sup>t</sup> number cjky202209; Ministry of Science and Technology of China, National Key Research and Development Plan, gran<sup>t</sup> number 2016YFD0401302.

**Institutional Review Board Statement:** Not applicable.

**Informed Consent Statement:** Not applicable.

**Data Availability Statement:** Not applicable.

**Conflicts of Interest:** The authors declare no conflict of interest.
