All perfect praise be to Allaah, The Lord of the Worlds. I testify that there is none worthy of worship except Allaah, and that Muhammad is His slave and Messenger.
There is a difference in opinion among the scholars on whether it is better to say "Bismillaah" or "Bismillaahir-Rahmaanir-Raheem" before eating or drinking. The predominant opinion is that one must only say: "Bismillaah" in the situations where the Prophet has been reported to have said it only, such as before eating and drinking. But it should not be condemned if someone says it in full (Bismillaahir-Rahmaanir-Raheem), if he does so acting upon the opinion of the scholars who permit saying so.
Allaah knows best.