Beer dispensing machines and mechanical systems comprised of blending machines and foam-detection equipment for infusing and mixing gases, including nitrogen, carbon dioxide, and custom gas blends, into beer for consistent carbonation, nitrogenation, and foam stability; machine components for gas-infused draft beer dispensing machines, namely, gas regulators, gas mixers, gas generators, gas cylinders, infusion chambers, and foam detectors; mechanical draft beer systems comprised of blending m...