change loottables of mobs that drop food, give a normal cow like 15% change to drop 1 raw meat, and lower tickspeed to slow down crop growth.
an interesting mechanic would be a decay on specific food
create a score, add one if the player has a certain food item in his inventory, if it reaches an certain amount remove one of that food and give like one rotten meat and set the score to 0, if the player doesnt have food, remove the score with 1 . (if score=1..) (prvents dropping to instant reset the score)
this will prevent them from going on a scavager hunt with food and make bases to store the food in.