This invention provides smoking compositions which contain a .beta.-hydroxy-.gamma.-ketoester compound as a flavorant-release additive. In one of its embodiments, this invention provides tobacco compositions which contain a flavorant-release additive such as dodecyl 3-hydroxy-2,2,3-trimethyl-4-oxopentanoate: ##STR1## Under cigarette smoking conditions the above illustrated .beta.-hydroxy-.gamma.-keto ester pyrolyzes into 2,3-butanedione and other products which enhance the flavor of the mainstream smoke and the aroma of sidestream smoke.