Kate Beckinsale makes sure her mouth is minty fresh before she kisses her co-stars - because she is paranoid she has bad breath.The 32-year-old actress, who smooched with Josh Hartnett and Ben Affleck in 'Pearl Harbour' and locked lips with Leonardo DiCaprio in 'The Aviator', has revealed she uses peppermint oil to taste good before puckering up on-screen.However, Beckinsale, who is who is married to director Len Wiseman, has revealed she once had a painful peppermint mishap before shooting one scene.She said: "I use pure peppermint oil before kissing scenes, but I got it in my eyes once and the shoot had to be delayed for an hour after they puffed up."