A method of manufacturing a fibrous water soluble product having particles, including: a) providing a first continuous water soluble fibrous substrate including a first side and moving in a first direction, b) providing a discretizing unit including one or more pockets comprising an opening; c) providing a continuous feed of first particles to at least one of the one or more pockets of the discretizing unit through the pocket opening at least partially filling the at least one of the one or more pockets, d) delivering the first particles from the pocket through the opening onto a portion of the first side of the first continuous water soluble fibrous substrate, and e) at least partially covering the first side of the first continuous water soluble fibrous substrate.