1. A capsule for preparing a food product in a device adapted to supply liquid to a capsule containing at least one compartment (13) with food ingredients mixed with the supplied liquid for preparing a food product and a filter for removing contaminants contained in the liquid, characterized in that the filter is made in the form of a filtering device (18), consisting of a filtering membrane (20) and an outlet wall (23), on which the filtering membrane rests, while in the outlet wall at least one fluid outlet (26) is provided in communication with said compartment (13) .2. A capsule according to claim 1, characterized in that the outlet (26) for the liquid is axially offset from the filter surface of the filter membrane (20). 3. The capsule according to claim 1, characterized in that the filtering membrane is a microporous membrane. A capsule according to claim 1, characterized in that the filtering device (18) contains a relatively rigid casing (19) in which the filtering membrane (20) is enclosed. The capsule according to claim 4, characterized in that the filtering device (18) contains an inlet wall (22), which together with the outlet wall forms an inner chamber (29), into which a filter membrane (20) is placed, while the filter membrane (20) is additionally tightly attached along the edge (30) to the casing (19) .6. A capsule according to claim 5, characterized in that the casing (19) consists of two halves joined together (37, 38), between which a filter membrane is clamped or welded along the edge (20) .7. A capsule according to any one of claims 5 or 6, characterized in that in the inlet wall (22)1. Капсула для приготовления пищевого продукта в устройстве, приспособленном для подачи жидкости в капсулу, содержащая по меньшей мере один отсек (13) с пищевыми ингредиентами, смешиваемыми с подаваемой жидкостью для приготовления пищевого продукта, и фильтр, предназначенный для удаления содержащихся в жидкости загрязнений, характеризующаяся тем, что фильтр выполнен