TSA Redefines Physics, Says Peanut Butter Is A Liquid

The Transportation Security Administration has an almost ‘through the looking glass’ way of describing what they do and do not permit, going so far as to redefine physics to their liking.

You can bring disabled bullets through security, and you can bring ice through security, but you cannot bring ice shaped like disabled bullets through security. Put another way, spent shell casings are fine but not if they can cool drinks.

While the TSA limits liquids through their checkpoints to 3.4 ounces per container, and in total not more than 100 milliliters, per passenger, for years I’ve pointed out that you can bring unlimited amounts of liquids through a checkpoint if you freeze them first. Because physics. Frozen liquids are solids. The TSA actually endorses this interpretation.

However they do not always respect physics. According to TSA, peanut butter is a liquid ‘because it conforms to the shape of its container’. Peanut butter is subject to 3.4 ounce / 100 milliliter rules. No distinction is drawn between chunky and creamy! And of course ice also conforms to the shape of its container, too.

One class of words in Newspeak “consisted entirely of scientific and technical terms” which “resembled the scientific terms in use today,” but the Party defined “them rigidly and strip them of undesirable meanings.” George Orwell wrote,

There was no vocabulary expressing the function of Science as a habit of mind, or a method of thought irrespective of its particular branches. There was, indeed, no word for ‘Science,’ any meaning that it could possibly bear being already sufficiently covered by the word Ingsoc.

Sometimes TSA itself gets confused by its own Newspeak rules. For instance they posted to their website that sunscreen would be exempt from its rules but then claimed this was an error.

When you bring more than 100 milliliters of liquid to a security checkpoint, the agency does not call in a hazmat team to safely manage the biohazard. Instead they keep a bin by the checkpoint to toss them into. All of the dangerous liquids are combined together into the same bin, and allowed to accumulate next to passengers and agency employees. Even if they use language of danger, their behavior fails to match.

About Gary Leff

Gary Leff is one of the foremost experts in the field of miles, points, and frequent business travel - a topic he has covered since 2002. Co-founder of frequent flyer community InsideFlyer.com, emcee of the Freddie Awards, and named one of the "World's Top Travel Experts" by Conde' Nast Traveler (2010-Present) Gary has been a guest on most major news media, profiled in several top print publications, and published broadly on the topic of consumer loyalty. More About Gary »

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  1. Yes it is a liquid (well at least prohibited). I once had to throw out a jar of Hawaiian peanut butter I bought as a souvenir. Very sad. They said I could go back and check it but I figured my bag was long gone. Also people apparently smuggle pot inside peanut butter!

  2. Why are you saying it “redefines physics”? No physicist would tell you that Peanut Butter is a solid. It is 100% not. The solid/liquid dichnotomy is an oversimplification. Peanut Butter is a heterogeneous mixture which has properties of both. If you had to put it into one or the other – there is no correct answer.

  3. On my way to Australia next week a country that allows all liquids on Domestic flights.
    Our worries in this world are far greater than peanut butter on board or water
    This is a waste of our time.
    I have a joint replacement with some metal in it and no one in Australia has ever grabbed my and groped my butt or groin area nor felt up my junk.In the US I’m so called patted down intimately? majority of the time.

    As a well known well said blogger once said security theater with great actors.
    Been pulled aside for premium chocolates and then checked for bomb material on my hands
    Always the same dark chocolate the culprit
    Billions of dollars in security and we still don’t know the difference between a gun a bomb or a joint replacement without molesting and groping citizens and seniors?
    A part of me wishes I lived in Australia where there is some dignity and freedom when traveling and still a feeling of security.Perhaps I am missing something.

  4. Bunch of sickos spending their day groping our elderly population without reasonable suspicion. #EndTheTSA

  5. How about oranges vs apple? Which is more like a liquid? This is the organization that lets 10 people traveling together bring in 1/10 th of a liter each but 1 person cannot carry 1 liter. Idiotic

  6. You can make great overnight oats and a very delicious cake with the biscoff cookie butter, FYI

  7. Gel like substances, like toothpaste and peanut butter, are actually the most dangerous. However, the regulations are written as liquids, which is not the same thing. The TSA people would not be able to implement a ban on “dangerous gel like substances and weird liquids.”

  8. Gary, remember to update this post when someone is busted smuggling in peanut butter they’ve hidden in a body cavity.

  9. I’m terrified just looking at that huge collection of dangerous substances the TSA have collected at Syracuse. Seems very reckless behavior, these substances need to be handled with utmost caution!

  10. Lotus Biscoff Creamy Cookie Butter Spread is a peanut butter-like spread made of speculoos cookies. Speculoos are buttery, brown sugar and spice-flavored cookies similar to gingersnaps and popular in the Netherlands (and elsewhere). They’re traditionally served around the Christmas season. Is Biscoff Creamy Cookie Butter Spread liquid or solid?

  11. Angry Gary is at it again! Number one, here’s what the rule says..

    “You are allowed to bring a quart-sized bag of liquids, aerosols, gels, creams and pastes through the checkpoint.”

    Now it seems to me like peanut butter pretty clearly fits in one of those categories.

    Number two, what are you so mad about? I’d rather err on the side of caution and be safe in the air and be able to bring my peanut butter, chunky or smooth, on board.

    Grow up.

  12. Ice is considered a liquid by the TSA even though, by definition, ice is a solid. And before someone says “it can be melted,” chocolate can be melted in your hand but it’s not on the banned list. The technology exists today to identify which liquids are safe and which are potentially unsafe.

  13. Frozen liquids also conform to the shape of the container. But give it to the DHS “brain trust” to come up with some brainless excuses.

  14. “Number two, what are you so mad about? I’d rather err on the side of caution ”

    1) TSA has identified no active threat involving peanut-buttery substances
    2) Indeed, while there was a hypothetical plot involving liquids 17 years ago (that was fairly far-fetched but ok) since then TSA has said in court that they are unaware of any active threats against US aviation period
    3) Europe is moving away from liquids bans altogether
    4) TSA promised FOR YEARS to replace the liquids ban but has failed to do so

    There’s no ‘caution’ in this just stupidity.

  15. This is what you get when you upgrade rent-a-cops. The ones at the top will hire those who make them look competent. Why is glass not flagged, also? It is a very slow flowing liquid per some descriptions. The collection of liquids is shear lunacy if they are really to be considered dangerous. It is all a con.

  16. I will never forgive the HK airport security agents who stole my jar of Nutella while transiting home. The Taiwanese were fine with it, but it was obviously a danger to aviation security once it reached HK. While other countries have finally seen some success at fighting this particular strain of stupid, we here in the US are woefully behind.

  17. Science says that glass is a super-cooled liquid (look it up) so is TSA falling down on the job for letting glass through?

  18. I used to have similar battles with TSA with cottage cheese and yogurt every Monday morning and Thursday afternoon. Sometimes they were ok, most often not. I used to take a few cheap bad yogurts from the concierge lounge, stash them in my laptop bag and see if the X-ray scanner would spot them. Most of the time they went right through. Once I used an empty cottage cheese container to transport some fish leftover from last night’s dinner and got into an argument whether the scanner would allow it. She did not appreciate the smell when opening the lid to pass it through…

  19. @dwondermeant A part of me really wishes you lived in Australia.. specially during the full lockdown.

    Are you seriously writing about Australia and Freedom in the same sentence with a straight face? I always say being in America is a privilege many ppl don’t really deserve.

  20. You would think glass would be forbidden since you can take a beer bottle by the neck, smash the it against something and turn it into a weapon like they do in the old movies.

  21. The more stupid thing is caring about liquids in the first place, especially just over 100 ml of it in a single container. I think it’s a conspiracy to sell travel-sized containers.

  22. After a new directive a few months back about organic materials…My salt grinder keeps getting exxtra care. The TSA takes my salt grinder and grinds some of it onto 5 purple squares and then via eye dropper puts 5 different kinds of test liquid onto each of them.. It does not turn any color because it is just salt.. but it is getting old..I have traveled with salt and pepper grinders for over 10 years with NO issues. so I guess I must give up my salt grinder for future trips…

  23. Quote: Ken A says:
    March 23, 2023 at 2:23 pm
    Lotus Biscoff Creamy Cookie Butter Spread is a peanut butter-like spread made of speculoos cookies. Speculoos are buttery, brown sugar and spice-flavored cookies similar to gingersnaps and popular in the Netherlands (and elsewhere). They’re traditionally served around the Christmas season. Is Biscoff Creamy Cookie Butter Spread liquid or solid?

    Ken: I’m a Dutchman. Biscoff cookie spread is a Belgian abomination that no well thinking Dutchman would ever spread on anything. Biscoff cookies originate from Belgium. We Dutchmen (and Germans) eat Speculaas, a very different tupe of cookie (biscuit for Brits) that is very different in texture. The German variety is indeed mostly seasonal around Christmas, and might be adorned by almond slivers. They are also harder/crisper. And therefore also wrong 😉 Dutch Speculaas is eaten by itself or on a slice of buttered bread. #facts

  24. Ice does not take the shape of its container – water does so as it is freezing, but if you were to add ice to a container it would not spread out. Sounds like this writer failed science class and should delete this post – really makes you look dumb.

  25. Peanut Butter is a non-Newtonian fluid…as is Mayonnaise.

    Newtonian fluids such as water offer less resistance as you increase the speed of swirling it in a container.

    Non-Newtonian fluids offer more resistance as the speed of rotation increases.

    Maybe the TSA guidance needs to replace the term “liquid” with “fluid”

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