Optimization of Low-Temperature Plasma Inhibition of Potato Germination Using Response Surface Methodology

In order to solve the problems of tuber infection and nutrient loss caused by potato germination during storage, this paper conducted a systematic study using low-temperature plasma jet technology to inhibit potato germination and determine its optimal treatment conditions. This study focused on optimizing the plasma treatment parameters, including voltage, gas flow rate, and treatment time, to effectively control potato germination, reduce weight loss during storage, and determine the quality indexes such as hardness, crispness, and antioxidant enzyme activity of potatoes in storage. The study showed that the optimal conditions for plasma treatment of potatoes were voltage 18.05 kV, treatment time 20.21 s, and gas flow rate 12.79 L/min. Under these conditions, the germination rate of potatoes was significantly reduced to 31.42%, and the weight loss rate was reduced to 2.15%. For the convenience of operation, the parameters of the validation experiment were determined as a treatment voltage of 18 kV, treatment time of 20 s, and gas flow rate of 13 L/min. The resultant potato germination rate was 31.26%, and the weight loss rate was 2.29%. Compared with the blank control group, the plasma-treated group significantly increased the activities of potato antioxidant enzymes (CAT, SOD, etc.). After 16 days of storage, SOD (superoxide dismutase) activity and CAT (catalase) activity of the plasma-treated group increased by 52.63% and 29.27%, respectively, compared with the control; POD (peroxidase) and PPO (polyphenol oxidase) activities of the treated group increased by 8.69% and 18.58%, respectively, compared with the control. Compared with the blank control, the plasma treatment group increased the hardness and brittleness of potatoes. Specifically, the hardness of the treated group increased by 6.06% compared with the control, and the brittleness of the treated group decreased by only 24% within 16 days, compared with a 37.19% decrease in the control. In addition, plasma treatment also reduced the accumulation of reduced sugar and dry matter consumption, thus maintaining the storage quality of potatoes, in which reducing sugar in the treated group was reduced by 32.56% compared with the control group, and dry matter in the treated group was increased by 7.66% compared with the control group. Therefore, the reasonable use of plasma treatment can effectively inhibit and slow down the sprouting process of potatoes, which lays a foundation for revealing the mechanism of plasma technology in inhibiting potato sprouting and improving its quality.