The present invention describes a process comprising a) subjecting a microorganism to autolysis under conditions at which a substantial part of the RNA remains in a form degradable into 5&prime；-ribonucleotides； b) subjecting the autolysate to solid/liquid separation and recovering the RNA-containing cell wall fraction； and c) converting the RNA in the recovered RNA-containing cell wall fraction into 5&prime；-ribonucleotides, whereby the solid/liquid separation in step b) is done at a pH of lower than 5.1. Said process is simple and allows for the production of a very pure composition of 5&prime；-ribonucleotides. It also allows for the production of a very clear yeast extract.
