Once one says a bracha on food or a mitzvah, the food must immediatly be consumed or the mitzvah performed without interruption. Speaking between the bracha and action is not permitted. The Chayei Adam (klal #5) has an interesting safeik: what if one speaks only 1 or 2 words between the mitzvah and the action?
What difference does it make how many words are spoken? The rule is "toch k'dei dibur k'dibur damei" -- a break of less time than it takes to say "shalom alecha rebbi" is not considered a break or interruption. In this case would we say that since the action occurs within toch k'dei dibur of the bracha it is considered simultaneous to the bracha, or would we say that an interruption has occurred, regardless of how short its duration?