Pulsed Electric Fields (PEF) Treatment Prior to Hot-Air and Microwave Drying of Yellow- and Purple-Fleshed Potatoes

Abstract

This study investigated the impact of pulsed electric fields (PEF) treatment combined with hot-air (HA) and microwave (MW) drying on the quality attributes of yellow and purple potato samples. PEF + HA and PEF + MW treatments showed no significant difference in total phenolic content for yellow potatoes. However, the raw purple sample exhibited significantly higher phenolic content compared to purple PEF1 and PEF3 samples. DPPH antioxidant activity for yellow and purple potatoes ranged from 18.48 to 33.19% with HA drying, and from 21.38 to 39.94% with MW drying. MW drying following PEF treatment was more effective in enhancing antioxidant activity compared to HA drying. However, it was observed that PEF levels had no statistical effect on total monomeric anthocyanin. PEF treatment prior to drying may be recommended in practice as it does not cause structural changes in SEM analysis. According to FTIR results, PEF and drying processes caused some changes in the chemical structure of potato samples. In the PCA results, the untreated purple HA sample exhibited characteristics that were most similar to those of the raw purple potato sample. Conversely, the yellow PEF + MW and untreated yellow with MW samples displayed properties closest to the raw yellow potato samples. According to chemometric analysis, the models exhibit high r_CV and r_Pre values coupled with low RMSEC and RMSEP values and negligible disparities between them, indicating strong correlations between the predicted and reference values.