The invention is directed to a process for preparing a milk product from a raw milk feed comprising microorganisms as obtained by milking a milk delivering animal by separating the microorganism from the raw milk by means of microfiltration. A milk product poor in microorganisms and a retentate milk product enriched in microorganism relative to the raw milk is obtained. The microfiltration is performed as a cross-flow filtration over a sieve, which sieve comprises of a coated silicon cross-flow surface plate with openings that are smaller than the dimensions of the microorganisms present in the raw milk feed and wherein over the sieve a high frequency back pulsing is applied. Microfiltration is performed within 8 hours from obtaining the raw milk feed by milking.
