when my son asked me if there will be food in heaven.

Jesus clearly mentioned the new wine during the last supper. The bible also mentions the banquet in honor of Christ, the Lamb of God.

When Jesus was resurrected, he ate fish by the lake of Galilee. It is fantastically interesting to speculate about the dynamic relation of this world's atoms and the next world's. John Pokinghorn, physicist and Anglican priest (and Templeton prize winner), has done that in his new book.