Cold plasma decontamination of brown rice grains: Impact on biochemical and sensory qualities of their corresponding seedlings and aqueous tea infusions

Abstract

Germinated brown rice is nutritionally superior to its ungerminated counterpart. However, germination may allow multiplication of grain-associated contaminants. Therefore, in the present study, the suitability of corona discharge plasma jet (CDPJ) as a disinfectant prior to germination was tested. CDPJ was generated under atmospheric pressure conditions using a 20 kV DC power source and at 1.5 A current. CDPJ treatment of brown rice was found effective in the decontamination of grain contaminants, namely aerobic bacteria as well as yeasts and molds. Moreover, the treatment unaffected germination rate and positively affected the weight and length of their (treated grains) corresponding seedlings. DPPH and ABTS radical scavenging activities as well as total phenolic content of the seedlings were positively influenced by CDPJ treatment. Also, the plasma treatment did not alter the sensory qualities of corresponding aqueous tea infusions. In conclusion, CDPJ could potentially be used for the improvement of microbial quality and safety of brown rice grains, with positive effects on biochemical qualities and no negative effects on sensory characteristics of their corresponding seedlings and aqueous tea infusions. © 2020 Elsevier Ltd