Cool, nice job getting a new game made already. The concept is amusing and the assets all fit together pretty well. One thing that I think could be improved would be to prevent the food pickups from interrupting the player's movement (maybe with triggers?).
I'm guessing the food is a regular collider and rigid body? If so, the stutter is probably from the food applying force to the player, since the player is basically running into a wall. Making the food collider a trigger and removing the rigid body from it should get rid of the stutter, if I remember Unity correctly (double check me on that). A trigger is just a collider that doesn't obstruct other colliders, so it's good for scripting "events" vs. hard physical objects.
There are a bunch of confusing rules about collisions, so the Unity manual is a key resource and reference for those.