Officially from tsa.gov in the section on traveling with children:
Medications, baby formula and food, breast milk, and juice are allowed in reasonable quantities exceeding three ounces and are not required to be in the zip-top bag. Declare these items for inspection at the checkpoint. Click here to learn more about 3-1-1
All items including formula, breast milk, and juice will be inspected, however, you or your infant or toddler will not be asked to test or taste breast milk, formula, or juice. Our Security Officers may test liquid exemptions (exempt items more than 3 ounces) for explosives.