A tobacco material and a process for the treatment of tobacco are provided. The process comprises securing the tobacco within a moisture-retaining material and exposing the tobacco material to an ambient processing temperature of at least about 45° C., with the tobacco having a packing density of at least 200 kg/m3 on a dry matter weight base at the start of the process and a moisture content of between about 10% and 23%. The TSNA content of the tobacco material is maintained at a relatively constant level during the process.