Pulsed TV holography is an all-electronic version of pulsed holographic interferometry. Such a system was used to study ignition of pre-mixed flammable gases. The object was recorded in its undisturbed and disturbed state followed by an evaluation of the changes in refractive index field between those two states. The essential components of the set-up are an injection seeded, twin cavity double pulsed Nd:YAG laser and a CCD camera. A focused laser pulse from the same laser that was used for the recording of the digital hologram initiated the ignition of the pre-mixed gas. Results from the recordings show the ignition process. From the experimental phase maps the refractive index of the gas mixture could be determined. This method makes it possible to determine the proportion of components in a pre-mixed flammable gas in situ.