MIAMI -- Fruitcakes are sweet, festive, and some people even think they taste good, but airport security workers say they might not fly if you're traveling this holiday season.

Transportation Safety Administration officials say the fruitcakes many people carry as gifts when they travel can cause problems with the new airport scanners.

Officials say the problem is that fruitcakes are so dense the X-ray equipment used at security checkpoints nationwide might mistake them for bombs.

So, this year, travelers are advised to pack fruitcakes, plus other dense items like chocolate blocks and cheese that can also be mistaken for explosives, in their carry-on bags instead of inside checked luggage.

Hundreds of airports across the country have installed new bomb detectors to comply with tighter security measures put in place after Sept. 11, 2001.

More tips from the TSA:

Don't pack food or drinks in checked-in luggage.

Don't wrap any gifts; they will have to be unwrapped for screening at the checkpoint.

Pack shoes last, so they're at the top of the suitcase. That way it's easier for screeners to search them.

The TSA offers more travel safety tips at www.tsa.com.