Is it permissible to begin prayer while chewing gum, without moving it or swallowing anything that comes from it?

The jurists dislike placing anything in the mouth during prayer because it contradicts proper humility (khushu') and prevents the correct pronunciation of letters. Merely placing gum in the mouth is disliked (makruh), and chewing it or swallowing any dissolved parts of it invalidates the prayer. If the gum is new and dissolves, the prayer is invalidated by placing it in the mouth. However, if it is used and does not dissolve, the prayer is not invalidated by placing it in the mouth.