My Food:

We have had a total of 13 dogs during our marriage.  All German Shepherds except four. We train them in our way. For example: our home is small so instead of taking up room with a table we eat on trays in  the living room. Our  dogs could easily help themselves to what is on our trays but they don't. They will come up and look, maybe take a sniff but not touch our food. All our dogs are rescue and when we first adopt them they will try to sneak a bite or lick. We would in a calm voice and by using our hands as a fence between them and our food (back of hands out) tell them this was not allowed. 

They now will look and sniff but not touch or lick. We calmly and gently teach them to be good family members. We don't raise our voice or push them back - just gently show them how far they can go.  To push becomes a game or challenge and hands - palms out - is aggressive or threatening. 

 This is how we teach and interact with all our dogs and it only takes a few times. They look, sniff and go lay down. If we set our tray aside they leave it alone. Before they are trained they would help themselves to something but training is essential. Doing it the right way is just as important. 

Once they know the parameters they seek to please us and we live harmoniously together. We reinforce that behavior by not peeking or looking at them to be sure they behave,. We trust them and show it by displaying our trust and they respond accordingly.