question: How does a popcorn pop?
comment: It’s a special variety of corn where the hardened kernels have a squishy inside with a bit of water. This water turns to steam when cooked and the squishy inside liquefies. The steam pressure pops the kernel open and the insides rapidly cool down into the weird shapes we see.
passages: As the oil and the water within the kernel are heated, they turn the moisture in the kernel into pressurized steam. Under these conditions, the starch inside the kernel gelatinizes, softens, and becomes pliable. The internal pressure of the entrapped steam continues to increase until the breaking point of the hull is reached: a pressure of approximately and a temperature of . The hull thereupon ruptures rapidly and explodes, causing a sudden drop in pressure inside the kernel and a corresponding rapid expansion of the steam, which expands the starch and proteins of the endosperm into airy foam. As the foam rapidly cools, the starch and protein polymers set into the familiar crispy puff. Special varieties are grown to give improved popping yield. Though the kernels of some wild types will pop, the cultivated strain is "Zea mays everta," which is a special kind of flint corn.
   Section::::Cooking methods.
  
  Popcorn can be cooked with butter or oil. Although small quantities can be popped in a stove-top kettle or pot in a home kitchen, commercial sale of freshly popped popcorn employs specially designed popcorn machines, which were invented in Chicago, Illinois, by Charles Cretors in 1885. Cretors successfully introduced his invention at the Columbian Exposition in 1893. At this same world's fair, F.W. Rueckheim introduced a molasses-flavored "Candied Popcorn", the first caramel corn; his brother, Louis Ruekheim, slightly altered the recipe and introduced it as Cracker Jack popcorn in 1896.
   Tiny but Mighty Popcorn
  
  Tiny but Mighty Popcorn is an American brand of heirloom popcorn, introduced in 1981, when Iowa farmer Richard Kelty founded K&K Popcorn. Iowa farmers Gene and Lynn Mealhow later purchased the company in 1999, and subsequently renamed it.
  
  Section::::History.
  
  Section::::History.:Kelty family.
   Popping of the kernels was achieved by hand on the stove-top through the 19th century. Kernels were sold on the East Coast of the United States under names such as "Pearls" or "Nonpareil". The term "popped corn" first appeared in John Russell Bartlett's 1848 "Dictionary of Americanisms". Popcorn is an ingredient in Cracker Jack, and in the early years of the product, it was popped by hand.
   List of popcorn brands
  
  This is a list of notable popcorn brands. Popcorn, also known as popping corn, is a type of corn (maize, "Zea mays var. everta") that expands from the kernel and puffs up when heated. Popcorn is able to pop because its kernels have a hard moisture-sealed hull and a dense starchy interior. Pressure builds inside the kernel, and a small explosion (or "pop") is the end result. Some strains of corn are now cultivated specifically as popping corns.
   Charles Cretors traveled the Midwest and settled in Fort Scott, Kansas for a few years, and then Decatur, Illinois. He spent his time working in the painting and contracting business, opened a bakery, and eventually a confectionery shop. As each venture led to the next, Cretors discovered he had a passion for how things worked.
   Popcorn maker
  
  A popcorn maker (also called a popcorn popper) is a machine used to pop popcorn. Since ancient times, popcorn has been a popular snack food, produced through the explosive expansion of kernels of heated corn (maize). Commercial large scale popcorn machines were invented by Charles Cretors in the late 19th century. Many types of small scale home methods for popping corn also exist.
   Popcorn's accessibility increased rapidly in the 1890s with Charles Cretors' invention of the popcorn maker. Cretors, a Chicago candy store owner, created a number of steam-powered machines for roasting nuts and applied the technology to the corn kernels. By the turn of the century, Cretors had created and deployed street carts equipped with steam-powered popcorn makers.
   Popcorn
  
  Popcorn (popped corn, popcorns or pop-corn) is a variety of corn kernel, which expands and puffs up when heated.
  
  A popcorn kernel's strong hull contains the seed's hard, starchy endosperm with 14–20% moisture, which turns to steam as the kernel is heated. Pressure from the steam continues to build until the hull ruptures, allowing the kernel to forcefully expand from 20 to 50 times its original size—and finally, cool.
   A different method of popcorn-making involves the "popcorn hammer", a large cast-iron canister that is sealed with a heavy lid and slowly turned over a fire in rotisserie fashion.
  
  Section::::Cooking methods.:Expansion and yield.
   Puffed grain
  
  Puffed grains have been made for centuries with the simplest methods like popping popcorn. Modern puffed grains are often created using high temperature, pressure, or extrusion.
   Section::::Terminology.
   Corn Popper
  
  The Corn Popper is a toy manufactured by Fisher-Price since 1957. Aimed at pre-schoolers, when the Corn Popper is pushed or pulled, colored balls inside a plastic dome bounce and create a popping, bouncing noise.
  
  Section::::History.
   As movie theater attendance grew through the 1920s, Cretors began designing machines that could pop and hold more of the product. Popcorn continued to grow in popularity through the Great Depression due to its low cost.
  
  Section::::History.:During World War II.
   As an addition to the confectionery shop, Cretors purchased a peanut roaster to broaden his offerings to include fresh roasted peanuts. Not satisfied with how the machine worked, he redesigned it to work better. It was at this time that Cretors moved his wife and family to Chicago where he felt he could become a commercial success by selling his new machine. It was 1885.
   When the popcorn has finished popping, sometimes unpopped kernels remain. Known in the popcorn industry as "old maids", these kernels fail to pop because they do not have enough moisture to create enough steam for an explosion. Re-hydrating prior to popping usually results in eliminating the unpopped kernels.
   Popping results are sensitive to the rate at which the kernels are heated. If heated too quickly, the steam in the outer layers of the kernel can reach high pressures and rupture the hull before the starch in the center of the kernel can fully gelatinize, leading to partially popped kernels with hard centers. Heating too slowly leads to entirely unpopped kernels: the tip of the kernel, where it attached to the cob, is not entirely moisture-proof, and when heated slowly, the steam can leak out of the tip fast enough to keep the pressure from rising sufficiently to break the hull and cause the pop.
   American Pop Corn Company
  
  The American Pop Corn Company is a family owned popcorn producer. Founded in 1914, it is the oldest popcorn company in the United States. Its only brand, Jolly Time, is sold globally and in every state in America. It employs 185 people, and its headquarters are in Sioux City, Iowa.
  
  Section::::History.
  
  The American Pop Corn Company's founder, Cloid H. Smith, made many business ventures during his youth; unsatisfied with the price pop corn from his farm was being sold, he decided to sell his own.
   In the "MythBusters" episode, "Car vs. Rain", first broadcast on June 17, 2009, the "MythBusters" team tried to determine whether the final scene in the film, the destruction of Dr. Hathaway's house with laser-popped popcorn, is actually possible. First they used a ten-watt laser to pop a single kernel wrapped in aluminum foil, showing that popping corn is possible with a laser, then they tested a scaled-down model of a house. The popcorn was popped through induction heating because a sufficiently large laser was not available. The result was that the popcorn was unable to expand sufficiently to break glass, much less break open a door or move the house off its foundation. Instead, it ceased to expand and then simply charred.
   BULLET::::- A popcorn bag is a specially designed, microwaveable bag that contains popcorn, along with oil, spices and seasoning. The bag is typically partially folded when it is placed in a microwave oven, and inflates as a result of steam pressure from the heated kernels. The earliest patent for the popcorn bag, U.S. patent #4,267,420 was filed on October 12, 1978 by William A. Brastad of Minneapolis and issued on May 12, 1981.
  
  1978 Bulletin board system
   At the time of the Mealhow purchase, K&K Popcorn was sold through Fareway stores. The Mealhows were initially unsuccessful in convincing Whole Foods Market to carry their product. One store manager in Chicago ultimately agreed to stock the product for a month; the manager contacted the family 10 days later to request additional stock after it sold out. The company's popcorn was eventually carried in every Whole Foods store in Chicago. By 2000, the company's popcorn was advertised as being the world's smallest; Gene Mealhow stated, "The smaller the kernel, the better the flavor."
   A chance meeting happened between Cretors and a traveling salesman who purchased a bag of roasted peanuts. The salesman, J.M Savage, was very intrigued with the new peanut roaster, and offered to sell it in his territory. Cretors agreed to the proposal, and hired his first salesman.
   The corn grown by Kelty was never hybridized or genetically modified. Kelty's stalks would reach a height of four to five feet. Each kernel was capable of producing four to six stalks with three to four ears of corn each, unlike field corn. Each ear of corn was grown to be less than three inches long. The characteristics of Kelty's popcorn were created through open pollination, seed selection, and roguing.
  
  Section::::History.:Mealhow purchase.
   Since 1854, the ancestors of Richard Kelty (1936-2015) had been growing a heirloom popcorn variety out of small kernels, whose hulls would disintegrate after being popped, resulting in a richer taste. The popcorn had been introduced to the Kelty family by Native Americans, who shared it with them. The Kelty family had never sold the popcorn, which was only grown for personal consumption.
   After Richard Kelty retired from the military in the mid-1970s, he obtained a handful of the corn from a relative and planted it on his farm in Urbana, Iowa. Eventually, Kelty and his wife, Rita, annually planted four rows of popcorn behind their house, which later increased to ten rows after their friends and neighbors requested more for their consumption. Kelty then chose to begin selling the popcorn, and founded K&K Popcorn in 1981. Kelty operated the business with his wife. 
  