Meter electronics (20) for determining a void fraction of gas in a flow material flowing through a flow meter (5) is provided according to an embodiment of the invention. The meter electronics (20) includes an interface (201) for receiving a frequency response of the flow material and a processing system (203) in communication with the interface (201). The processing system (203) is configured to receive the frequency response from the interface (201), break out the frequency response into at least a gas frequency component and a fluid frequency component, and determine the void fraction of gas from the frequency response and one or more of the gas frequency component and the fluid frequency component.