Low-energy short-term cold atmospheric plasma: Controlling the inactivation efficacy of bacterial spores in powders

•SMD afterglow atmospheric plasma is effective in B. subtilis spores inactivation.•Very low plasma power density (5 mW/cm2) is required to reduce 4 log10 cycles.•Inactivation efficacy is a function of applied surface energy (J/cm2)•Powder load (mg/cm2) is a limiting factor in decontamination of biopolymers.•Etching via RNS is considered being the main mechanism of inactivation.