A beverage system for producing a coffee or tea beverage that includes a beverage machine that includes: a holder configured to receive and support a portion capsule, and a pump controlled to push water into the capsule to produce the beverage. The portion capsule includes a metal cover attached to a metal base element. The cavity has a plurality of ribs that are radially spaced, vertically oriented, and configured to extend toward a central portion thereof. The ribs are free from extending all the way to a bottom of the cavity. The base element has a side wall with an electrically conductive section and radially spaced and vertically oriented grooves, the grooves being free from extending all the way to a bottom of the base element and are also free from extending all the way to a region of the side wall that is immediately adjacent to the flange.