Optimization of double-cooking condition for low potassium potatoes using response surface methodology (RSM)

This study aimed to establish optimal double-cooking condition using response surface methodology that maintained hardness while maximizing potassium reduction rate. The experimental design was based on the first cooking time (4.5–5.5 min) and rinsing time (20–60 s) through central composite design. This study suggested an optimal double-cooking condition of 5.5 min for first cooking and 57.57 s for rinsing. The model corroborated that the double-cooking condition significantly influenced dependent variables, including potassium reduction rate, hardness, and color (b-value). As the first cooking time increased, the potassium reduction rate increased and the hardness and b-value decreased. SEM revealed that double-cooked potato had more organized and netted structure. This structure could be helpful to maintain hardness, but relatively large amount of potassium could be leached out. The established optimal double-cooking condition for potatoes holds promise for broadening the dietary options for chronic kidney disease patients.