Impossible Leavening

In comedy shows, yeast tends to be treated as far more volatile and powerful than it actually is. A less than stellar baker will add more yeast to a recipe than it needs, often many times more, and the dough reacts explosively. If you're lucky, all that you get is a mess in the kitchen, or a pizza that nearly fills the oven as it bakes. However, it's just as common to see the dough explode all over the kitchen or, in extreme cases, come to life. Occasionally, baking powder and baking soda, also known for their leavening properties, can cause much the same problems.

Compare Oven Logic, for when the disaster is the result of temperature instead of yeast. If the aspiring chef combines the two, you might as well just start saving for a new kitchen altogether.


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     Comic Books  

  • There's a Goof Troop story with this happening in Pete's kitchen, then whole house: When instructed to add 3 drops of ultra-concentrated yeast five minutes before the cake is done, Pete just poured the whole bottle in at the start and went for the TV.
  • This comic book style ad refers to the I Love Lucy episode mentioned below.

     Comic Strip  

  • In For Better or for Worse, Elly accidentally adds far too much yeast when making a large amount of bread for an event, and hurriedly stashes it in the trash can outside so John won't know. Cue John, in the last panel, staring at a trash can whose lid is being lifted into the air by a tremendous mass of dough.


  • The Three Stooges did this, but not with bread - with beer! In "Beer Barrel Polecats", the trio were trying to make their own beer. The directions said to use three cakes of yeast, and each stooge, not knowing the others had already done so, put in three cakes. It ends up spilling out of the large crock they're using to brew it in and they eventually fill a bathtub full.


  • In The Bliss Bakery series, this trope is justified by magical ingredients. Which make it possible to ruin kitchens on a much larger scale. The positive side of this is impossibly fluffy, airy cakes.

     Live Action TV  

  • I Love Lucy. In "Pioneer Women", when the oven containing the result of this trope was opened, the bread came out in a huge oven-shaped loaf, far longer than the oven was deep, stretching all the way across the kitchen and pinning Lucy to the opposite wall.
  • On Fraggle Rock, Ma Gorg puts too much yeast and other ingredients in her souffle. She ends up fighting it until it explodes and leaves a huge mess.
  • In a Christmas Episode of Amen, perpetual bad cook Thelma actually gains some cooking skills from her days in the Army and prepares a delicious Christmas dinner for everyone—except for the rolls. When she calls the chef to thank him for his tutelage, she asks why his bread recipe required five pounds of yeast. The chef tells her that's because his recipe was meant to serve 600, whereas Thelma is only serving six. Cue the oven door opening and the dough engulfing the kitchen.


  • In Das Geheimnis im Hefetig, the story starts by Reinhard Mey baking a cake that explodes quite violently. The explosion is strong enough that it attracts the attention of several secret services.

     Western Animation  

  • In an episode of Ed, Edd 'n' Eddy, the trio make pizza. Eddy, ignoring Edd's instructions for the proper amount, dumps in the whole container of yeast for the dough. The dough rises so much that Eddy's fist gets stuck in the dough when he tries to punch it down, and Ed has to bellyflop on it to do the job.
  • In Hey Arnold!, the kids of the city work on the world's biggest pizza puff in a bid to break a world record. All seems well, until Sid reveals that he misunderstood "tsp" in the recipe. Instead of "teaspoons", he read it as "ten square pounds"! The resulting explosion of dough takes a good deal of the next day to wash off of the streets.
  • Weaponized by The Breadmaster, a villain on The Tick, first as bread bombs that can encase entire buildings when activated, and finally, as a giant souffle that will devour the whole city. Luckily, Tick manages to destroy it by generating a sonic boom while getting shot out of the Human Bullet's cannon.
  • Taken to its logical extreme in one episode of Muppet Babies, where an Imagine Spot has the fifty-foot Piggy Dough-Girl rampaging through the city: Bunsen tells Beaker to use the "Beast Blaster" to destroy it, but he ends up firing a "Yeast Blaster" at it instead, causing it to grow into a full-fledged Planet Eater.
  • In The Mr. Men Show episode "Restaurants", Miss Calamity is baking cinnamon buns. She names each ingredient she puts in the giant mixer as she puts it in: "Flour, sugar, milk, and just a little yeast to help the dough rise." But later on, she can't remember if she added the yeast, so she adds more yeast. This results in the dough filling up the bun shop, but Mr. Nosy and Mr. Small, who are outside the bun shop, don't even notice and leave without rescuing her!
  • An episode of Johnny Bravo has Johnny make pancakes for a rest home, with his own pancake recipe - 3 parts yeast, 8 parts yeast and yeast enhancer. The result is that the mix turns into a giant bread loaf that destroys the entire building.

     Real Life  

  • Averted because the gluten structures will collapse long before the gases reach critical density to cause an explosion. Without the gluten structures to hold the gases in, the gases will simply poof out of the bread. This will result in a product that kinda looks like Swiss cheese. Also, too much yeast growth will end up eating up the dough, which will result in weakening of the gluten structures rather than extreme expansion.
    • With some additional containment, though - such as sealing your fermenting yeast mixture in a screw-top glass bottle - it will explode just fine.
  • A popular (and rather disgusting) practical joke is to throw a cake of yeast into an open latrine pit. Bread dough and wine actually lack the nitrogen nutrients needed for the yeast to thrive (that's the reason why moonshiners are often shown throwing the fertilizer into the wort), but the shit most emphatically doesn't, and there's enough undigested sugars to make yeast happy. So you will end with an explosion of the most unpleasant kind, if only figuratively.