Different aspects of the invention refer to a disinfection apparatus, and corresponding method, for wood barrel disinfection using microwave shock pulse, MwSP, technology for the complete elimination of microbial populations. This is accomplished by a system which ensures deep and complete disinfection, however such that the temperature is maintained below material degradation level. Complete disinfection is achieved due to effectiveness up to the deepest layers. The wooden barrel material is however preserved, due to the non-harmful nature of the dosage regime programmed into the radio frequency emission.