I really don't know when it started. We all have to eat and drink for nourishment, but my attraction to food is a bit more than the daily vitals. Babies learn quickly what they like and what really belongs on the floor under the high chair.
My mom used to love to tell the story of her reaction the first time I winged a teaspoon of carrots in her face. Of course, dad thought it was cute, but mom said she turned a new shade of crimson and had to be reminded that I was just sitting up and eating like a big girl. It's pretty obvious to me now that dear old mom clearly did not recognize the request of her junior epicurean for a fine citrus glaze on those carrots.