Just declare whatever you're bringing in. Here are some possible scenarios if you do an honest declaration:

1. Passport control asks what kind of food you brought in. You're not sent to ag.
2. Passport control asks what kind of food you brought in. You're sent to ag. And you have your bags quickly x-rayed.
3. Passport control asks what kind of food you brought in. You're sent to ag. And you have your bags quickly x-rayed. And then someone asks questions.
does a visual inspection.
4. Passport control asks what kind of food you brought in. You're sent to ag. And you have your bags quickly x-rayed. And then someone asks questions. Finally, someone does a visual inspection.

This isn't for just the US - do it with any country: Make an honest declaration. Food confiscated will be for good reason, not for power trips, unlike other dealings with customs and TSA. No fines, nothing - if you make an honest declaration.