Effect of ultrasonic-assisted ethanol pretreatment osmotic dehydration on CO₂ puffing drying quality of potato slices

This study investigated the enhancement of drying efficiency for potato slices using a combination of ultrasonic-assisted ethanol (US + EH) pretreatment and puffing drying. The results show that the US + EH pretreatment significantly improves osmotic dehydration rates by promoting the formation of micro-channels within the potato slices, which facilitates efficient water exchange. This method enables rapid dehydration while retaining nutrients and enhancing the puffing characteristics during the expansion phase. Optimization of the expansion process was achieved through a quadratic regression orthogonal rotation combination test based on single-factor experiments. The optimal conditions for preparing potato slices were identified as a solid–liquid ratio of 1:7, a solution concentration of 64%, an ultrasonic treatment time of 10 min, and an ultrasonic temperature of 39 °C. Under these conditions, the potato slices exhibited higher VC content and a crispier structure, which effectively improved the drying process and product quality.