Microbial Reduction of Bitter Melon (Momordica charantia L.) and Chan Khao (Tarenna hoaensis Pitard) Herb Powder by Dielectric Barrier Discharge Plasma for Food Sanitary

Abstract

The influence of air plasma treatment on microbial inactivation contaminants in bitter melon (Momordica charantia L.) and Chan Khao (Tarenna hoaensis Pitard) powders, obtained from the local retail market in Nakhonnayok, has been investigated. The dielectric barrier discharge (DBD) air plasma model has been designed for in-package treatment by using a neon transformer.  From the microbial analysis, there were high amounts of total aerobic plate count (TPC) as well as total yeast and mold counts (TYM) contaminants in both samples.  It could be confirmed that the DBD air plasma treatment has a positive effect on microorganism reduction. Moreover, the color of air plasma-treated powders has still been chiefly preserved after the treatment process. The kinetics microbial inactivation process in this study has been found to be a single-slope survivor curve since the reduction rate is linear and increased with treatment time. The TPC and TYM concentration in the plasma-treated samples could be decreased to microbiologically qualify for the acceptance criteria of herbal drug preparations as indicated in the Thai Pharmacopoeia Volume I and II Supplement 2005 standard (TP Supplement 2005).