Well... here is the answer. It was the inside of the food. I spent two hours to model because I wanted it to look good. And after two hard hours of work I just wanted to see whole result recognized this:

My character has two left feet!!!! Oh no. But I was not angry about myself. I started to laugh because it really looks too strange.

Somehow I was happy about this mistake because I could model the foot better and got some more exercises in modeling.

The moral of this story? Even if you've done a stupid mistake. There's is always a good side of it. So keep on smiling and continue! :)