Providing infotainment services in Vehicular Adhoc Networks (VANETs) is a key functionality for the future intelligent transportation systems. However, the unique features of vehicular networks such as high velocity, intermittent communication links and dynamic density can induce severe performances degradation for infotainment services running on the six Service Channels (SCHs) available in the Dedicated Short Range Communication (DSRC). Although, the Wireless Access in the Vehicular Environment (WAVE) has been proposed for VANETs to support these applications and guarantee the QoS by proposing four different access categories, no service channel scheme has been proposed to ensure fair and interference-aware allocation. To fill this gap, in this work we propose ESCiVA, an Efficient Service Channel allocation Scheme in SDN-enabled VAnets to balance service traffic on the six SCHs and mitigate interferences between services provided on adjacent channels. Extensive simulation results confirm that ESCiVA outperforms the basic SCH allocation method, defined in the WAVE standard.