You can bring open food through security so long as it abides by the 3-1-1 and other TSA food rules. Following the same logic and limitations, you can also bring unopened, prepackaged or sealed food through TSA.

Yes, you can generally bring open food through TSA security, but with one major caveat: it must be solid food. Items like half-eaten sandwiches, slices of pizza, burgers, and dry snacks (even if the bag is open) are perfectly fine to bring through the checkpoint. However, any "liquid or gel" food items—even if they are part of an open meal—must still comply with the 3-1-1 rule. This means things like open containers of yogurt, hummus, salsa, soup, or even a half-finished jar of peanut butter will be confiscated if they are larger than 3.4 ounces (100ml). TSA officers may ask you to remove the food from your bag for separate screening to ensure it isn't hiding anything, and they may perform a "swab" test on the packaging. It is a peer-to-peer best practice to wrap your open food in clear plastic or a reusable container to keep it hygienic and to show the officer that the items are clearly identifiable as food. If you are traveling internationally, remember that while TSA lets it through the checkpoint, "Customs" at your destination may prohibit open fruits, vegetables, or meats.