US Patent 8474368 Mineral composite beverage brewing cup and cartridge

A beverage filter cartridge having a cup, a filter, a lid and at least one beverage ingredient is provided where the cup and lid are sealed together to form an interior chamber which is separated into a first and second compartments by the filter, which is preferably basket or cone shaped, and a beverage ingredient such as coffee is contained inside first compartment, and at least one of the cup, lid and filter contains calcium carbonate in an amount effective to either improve the ability of beverage makers to pierce the cup or to provide a means for the cartridge to absorb CO2 emitted by the ingredient thereby reducing the hold time to packing and reducing the number of defective cartridges.