Inhibition of Aspergillus flavus on agar media and brown rice cereal bars using cold atmospheric plasma treatment

This study aimed to optimize the operating parameters of cold atmospheric plasma treatment to inhibit the growth of Aspergillus flavus on agar media and brown rice cereal bars. The effects of argon plasma jet treatment on the growth of A. flavus on malt extract agar (MEA) at powers of 20 W and 40 W with exposure times at 5, 15 and 25 min were studied using response surface methodology (RSM) with a central composite face-centered (CCF) design. Multiple regression analysis indicated that plasma treatment at 40 W for 25 min is most effective for inhibiting growth of A. flavus on the agar medium. On brown rice cereal bars, plasma powered at 40 W for 20 min was capable of giving protection against A. flavus growth for up to 20 days under storage conditions of 25 °C and 100% RH. These results demonstrated the potential of cold atmospheric plasma jet treatment to control mold growth on various food products.

► We demonstrate that cold plasma jet treatment was able to inhibit Aspergillus flavus.
► The treatment time required is in an order of minutes.
► Cold plasma jet treatment destroyed conidiophores and the vesicle of Aspergillus flavus.
► As a pasteurization technique, cold plasma jet was capable of extending shelf-life of cereal products.