Minimum the food would be confiscated if it is on the banned list. You could also be fined, possibly arrested/jailed/deported if you were trying to smuggle goods (which it kind of sounds like you are) vs. just forgetting or being ignorant of the rules.

If you declare it and it is not restricted (some meats, agriculture, etc.), you will be on your way with a bag inspection at the worst.

Lying to customs in any country is a very stupid thing to do. There is also a very good chance that a friendly beagle will find your food long before you even talk to customs.