The invention proposes a method for the production of a porous powder product containing a microorganism, from a liquid concentrate comprising at least one liquid microorganism culture and a carrier composition, the carrier composition comprising at least one carbohydrate and at least one protein, the method comprising the steps of: i) preparing the liquid concentrate to have both a temperature of between and 40°C and a viscosity greater than 150 mPa.s ii) injecting a food grade gas into the prepared concentrate at a pressure greater than 0.3 MPa to intimately incorporate the gas into the liquid concentrate and form a stable foam with a density of between about 0.6 to about 1.2 kg/l iii) conveying the foam to an atomizing device wherein the pressure of the foam is reduced from 0.3 MPa to atmospheric pressure to provide a partially dried product and iv) exposing the partially dried product to a drying media to reduce both the moisture content to less than 5% moisture and the water activity to less than 0.25 A
