Automated beverage brewing system

A brewing system for brewing a beverage from an extract contained in a sealed disposable cartridge, said system comprising:

• a housing defining a brewing chamber for receiving said cartridge;
• means associated with said housing means for piercing said cartridge to provide a first inlet and a first outlet communicating with the interior of said cartridge;
• a storage tank comprising a supply of liquid;
• a sealed metering chamber contained in said storage tank at least partially submerged in said liquid, said chamber being in communication with said storage tank via a second inlet and being in communication with said cartridge via a second outlet;
• valve means associated with said second inlet for admitting liquid into said chamber from said storage tank and for preventing reverse liquid flow from said chamber into said tank;
• means for delivering compressed air to said metering chamber to transfer a predetermined volume of liquid from said metering chamber via said second outlet for delivery to and through said cartridge via said first inlet and said first outlet, and for sensing the pressure of said compressed air and providing a sensed pressure signal value indicative thereof;
• and
• a controller that (i) commands said means for delivering to provide compressed air to said metering chamber, (ii) monitors said sensed pressure signal value and (iii) commands said means for delivering to terminate delivery of compressed air to said metering chamber after detecting that said sensed pressure signal value has dropped below a threshold value indicating said predetermined volume of liquid has been delivered through said second outlet.