The invention concerns a mixture of bacteria. Said mixture is a non starter culture which is free from metabolites and comprises at least one first bacterium selected from the species <i>Propionibacterium jensenii</i> and at least one second bacterium selected from the genus <i>Lactobacillus</i>. Furthermore, food, feeding stuff and medicaments comprising such a mixture, a method for manufacturing and storing such goods and the use of the mixture to inhibit fungi and bacteria are provided.