Effects of Cold Plasma Treatment on Production and Contents of Bioactive Substances in Broccoli Sprouts

In order to achieve the enrichment of sulforaphane, polyphenols, flavonoids and other bioactive substances in broccoli sprouts so as to reduce production costs, this study used plasma treatment induction method to treat broccoli sprouts. The plasma treatment conditions and its effects on the sprouts of different varieties of broccoli were studied. The results showed that the plasma treatment voltage and time had significant effects(P<0.05) on the germination state and the contents of bioactive compounds in broccoli sprouts. Under the conditions of voltage 30 kV and treatment time of 2 min, the germination rate, bud length and bud weight of broccoli sprouts after 5 days germination were significantly increased compared with the control. In addition, the sulforaphane content reached 3.24 mg/g DW, which was 6.75 times higher than that of untreated samples. There were significant differences (P<0.05) in the sulforaphane, total polyphenols, total flavonoids and antioxidant activity among different broccoli sprouts. MNL had the highest sulforaphane and glucosinolates content, while MTL and LY had the highest polyphenols and flavonoids content. After plasma treatment, WX, MNL, LY and LJ´s polyphenols and flavonoids content and antioxidation activity were all improved compared with control. In short, plasma treatment could be an effective way to enrich sulforaphane in broccoli sprouts, which would significantly improve the efficacy of sprouts and reduce the cost of sulforaphane acquisition.