CO2 Gas Volume Determination: The sample was equilibrated by gently inverting the sample bottle 20 times in 30 seconds and waited for bubbles to settle in the liquid. The sample was placed under the Zahmnagel tester and align crown with the piercing device. The snift valve was closed at the front of the tester. The grasp springs and cross bar was carefully lowered until the piercing needle rested on the crown. The crown was pierced forcing the cross bar down with a firm and rapid motion. The head pressure was released by carefully opening the snift valve, allowing the pressure to drop and close the valve closely. The bottom of the tester pad was held in one hand and the cross bar in the other hand. The tester was shaken vigorously in horizontal motion until the maximum pressure gauge read a constant pressure. The maximum pressure was recorded and the cross bar removed. A thermometer was inserted immediately and the temperature reading recorded. The pressure and temperature readings obtained were converted to gas volume using a volume chart.