This method comprises the following steps: (i) formation of drops of a first phase in a second phase substantially immiscible with the first phase; (ii) flow, in a flow line, of the drops; (iii) recovery of a dispersion comprising drops and second phase in a container; and (iv) injection of a solution into the flow line or at the outlet of the flow line, upstream of the container, the solution comprising at least one raw material which is not or is not very compatible with step (i) and/or step (ii).