| Polyphenol oxidase (PPO) and peroxidase (POD), responsible for enzymatic browning, cause technological and
also financial losses for producers. Through central composite design, the effects of time duration and voltage
magnitude using cold atmospheric plasma (CP) were investigated on enzyme activity of banana slices. During CP
treatment, PPO and POD activity decreased 70% and 100%, respectively. Total phenol and flavonoid content of
the samples increased, particularly as a result of exposure time; which contributed to more than 50% increment
in antioxidant activity. Optimum conditions for CP treatment was obtained at voltage 6.9 kV for 46 s. Vitamin B6
content was higher for optimal sample than untreated one and reached 0.8 μg/100 g. Slight decrease in hardness
of treated sample was obtained which was in accordance with porous structure obtained through morphology
testing. Considering efficient effect on enzyme inactivation and mild effect on physico-chemical properties, CP
can be a promising non-thermal process for fresh fruits blanching. |