Puffed grains are

grain A grain is a small, hard, dry fruit ( caryopsis) – with or without an attached hull layer – harvested for human or animal consumption. A grain crop is a grain-producing plant. The two main types of commercial grain crops are cereals and legum ...

s that have been expanded ("puffed") through processing. They have been made for centuries with the simplest methods like popping

popcorn Popcorn (also called popped corn, popcorns or pop-corn) is a variety of corn kernel which expands and puffs up when heated; the same names also refer to the foodstuff produced by the expansion. A popcorn kernel's strong hull contains the se ...

. Modern puffed grains are often created using high temperature, pressure, or

extrusion Extrusion is a process used to create objects of a fixed cross-sectional profile by pushing material through a die of the desired cross-section. Its two main advantages over other manufacturing processes are its ability to create very complex c ...

. People eat puffed grains in many ways, but it can be as simple as puffed grain alone and with sugar or salt for taste. Commercial products such as

corn flakes Corn flakes, or cornflakes, are a breakfast cereal made from toasting flakes of corn (maize). The cereal, originally made with wheat, was created by Will Kellogg in 1894 for patients at the Battle Creek Sanitarium where he worked with his broth ...

and

Corn Pops Corn Pops is a puffed grain breakfast cereal made by Kellogg's, described by the company as "crunchy sweetened popped-up corn cereal." The cereal was introduced in 1950 as "Corn Pops". In 1951, the name was changed to "Sugar Corn Pops" and later t ...

mix many ingredients into a homogeneous batter. The batter is then formed into shapes then toasted and/or extruded. This causes them to rise, but not puff or pop. Puffed grains can be healthful if plain, but when other ingredients are mixed with them they may lose some of their health benefits. Puffed grains are popular as

breakfast cereal Cereal, formally termed breakfast cereal (and further categorized as cold cereal or warm cereal), is a traditional breakfast food made from processed cereal grains. It is traditionally eaten as part of breakfast, or a snack food, primarily in We ...

s and in the form of

rice cake A rice cake may be any kind of food item made from rice that has been shaped, condensed, or otherwise combined into a single object. A wide variety of rice cakes exist in many different cultures in which rice is eaten and are particularly preval ...

s. While it is easy to recognize that cereals came from whole grains, the expansion factor for rice cakes is even greater, and the final product is somewhat more homogeneous.

History

The oldest puffed grain was found in west-central New Mexico in 1948 and 1950. Ears of popcorn were found that were up to 4,000 years old. These pieces of puffed grain were smaller than a penny to two inches in size and can be made in a similar way to popping popcorn. Rice has been puffed since ancient times using a technique called hot salt frying in which parboiled rice (e.g. steamed and then dried) is puffed by preheated salt. The modern process of making puffed grains was invented by Dr. Alexander P. Anderson in 1901 in Red Wing, Minnesota. He was doing an experiment dealing with the effect of heat and pressure on

corn starch Corn starch, maize starch, or cornflour (British English) is the starch derived from corn (maize) grain. The starch is obtained from the endosperm of the kernel. Corn starch is a common food ingredient, often used to thicken sauces or sou ...

granules where he put them in six glass tubes, sealed them, and put them in an oven until they changed color. When Dr. Anderson took them out and cracked them open an explosion happened; he had made the corn starch turn into a puffed, white mass."Dr. Alexander P. Anderson - 1982 Inductee." Minnesota Inventors Hall of Fame -. N.p., n.d. Web. 08 Apr. 2013. Dr. Anderson's invention of puffed grain was first introduced at the World's Fair in St. Louis in 1904. The puffed grain was shot from a battery of eight guns and on a poster, it was called “The Eighth Wonder of the World.”

Manufacture

Puffed rice can be produced using the simple but effective method of hot salt frying. Salt is heated in a pan until it is hot enough to pop rice added to it within seconds. Parboiled or dried pre-cooked rice is added to the heated contents of the pan and stirred. Puffing starts almost immediately and completes in less than a minute and the rice is scooped out by a sieve. Puffed grain machine - 04

High pressure puffed grain is created by placing whole grains under

high pressure In science and engineering the study of high pressure examines its effects on materials and the design and construction of devices, such as a diamond anvil cell, which can create high pressure. By ''high pressure'' is usually meant pressures of th ...

with

steam Steam is a substance containing water in the gas phase, and sometimes also an aerosol of liquid water droplets, or air. This may occur due to evaporation or due to boiling, where heat is applied until water reaches the enthalpy of vaporizatio ...

in a containment vessel. When the vessel's seal is suddenly broken, the entrained steam then flashes and bloats the

endosperm The endosperm is a tissue produced inside the seeds of most of the flowering plants following double fertilization. It is triploid (meaning three chromosome sets per nucleus) in most species, which may be auxin-driven. It surrounds the embryo an ...

of the

kernel Kernel may refer to: Computing * Kernel (operating system), the central component of most operating systems * Kernel (image processing), a matrix used for image convolution * Compute kernel, in GPGPU programming * Kernel method, in machine learn ...

, increasing its volume to many times its original size. Puffed rice or other grains are occasionally found as street food in

China China, officially the People's Republic of China (PRC), is a country in East Asia. It is the world's List of countries and dependencies by population, most populous country, with a Population of China, population exceeding 1.4 billion, slig ...

Korea Korea ( ko, 한국, or , ) is a peninsular region in East Asia. Since 1945, it has been divided at or near the 38th parallel, with North Korea (Democratic People's Republic of Korea) comprising its northern half and South Korea (Republic ...

(called ''"ppeong twigi"'' 뻥튀기), and

Japan Japan ( ja, 日本, or , and formally , ''Nihonkoku'') is an island country in East Asia. It is situated in the northwest Pacific Ocean, and is bordered on the west by the Sea of Japan, while extending from the Sea of Okhotsk in the n ...

(called ''"pon gashi"'' ポン菓子), where hawkers implement the puffing process using an integrated pushcart/puffer featuring a rotating steel

pressure chamber A pressure vessel is a container designed to hold gases or liquids at a pressure substantially different from the ambient pressure. Construction methods and materials may be chosen to suit the pressure application, and will depend on the size ...

heated over an open flame. The great booming sound produced by the release of pressure serves as advertising. Manufacturing puffed grain by venting a pressure chamber is essentially a batch process. To achieve large-scale efficiencies, continuous-process equipment has been developed whereby the pre-cooked cereal is injected into a high pressure steam chamber. It then exits the steam chamber via a

Venturi tube The Venturi effect is the reduction in fluid pressure that results when a fluid flows through a constricted section (or choke) of a pipe. The Venturi effect is named after its discoverer, the 18th century Italian physicist, Giovanni Battista ...

to an expansion chamber, where the puffed cereal is collected and conveyed to the next process step. These devices, generally called stream puffing machines, were perfected in the latter half of the 20th century in Switzerland and Italy, but are now available from manufacturers in China as well.

Puffable foods

Puffed wheat BMK.jpg, Puffed wheat Popcorn and pop sorghum.jpg, Popcorn (left) and popped sorghum (right) 09679jfFilipino cuisine foods desserts breads Landmarks Bulacanfvf 02.jpg, Filipino cornick made from glutinous corn that is puffed by soaking in water for three days, unlike

. Awaokoshi 01.jpg, Awaokoshi, puffed

millet Millets () are a highly varied group of small-seeded grasses, widely grown around the world as cereal crops or grains for fodder and human food. Most species generally referred to as millets belong to the tribe Paniceae, but some millets a ...

sweets from Japan

Examples

Puffed grain foods

Snacks A snack is a small portion of food generally eaten between meals. Snacks come in a variety of forms including packaged snack foods and other processed foods, as well as items made from fresh ingredients at home. Traditionally, snacks are ...

and food products made from puffed grain include: *

Amaranth ''Amaranthus'' is a cosmopolitan genus of annual or short-lived perennial plants collectively known as amaranths. Some amaranth species are cultivated as leaf vegetables, pseudocereals, and ornamental plants. Catkin-like cymes of densely p ...

** Alegría – Mexico *

Corn Maize ( ; ''Zea mays'' subsp. ''mays'', from es, maíz after tnq, mahiz), also known as corn (North American and Australian English), is a cereal grain first domesticated by indigenous peoples in southern Mexico about 10,000 years ago. The ...

(maize) (

Popcorn Popcorn (also called popped corn, popcorns or pop-corn) is a variety of corn kernel which expands and puffs up when heated; the same names also refer to the foodstuff produced by the expansion. A popcorn kernel's strong hull contains the se ...

) ** Bamba - Israel ** Buffies - Palestine ** Cheese puffs - U.S.A. ** Cornick - Philippines **

** Pasankalla - Bolivia **

Millet Millets () are a highly varied group of small-seeded grasses, widely grown around the world as cereal crops or grains for fodder and human food. Most species generally referred to as millets belong to the tribe Paniceae, but some millets a ...

**Awaokoshi, Japan - a puffed millet based sweet *

Rice Rice is the seed of the grass species '' Oryza sativa'' (Asian rice) or less commonly ''Oryza glaberrima'' (African rice). The name wild rice is usually used for species of the genera '' Zizania'' and '' Porteresia'', both wild and domesticat ...

Ampaw Ampaw, ampao or arroz inflado, usually anglicized as pop rice or puffed rice, is a Filipino sweet puffed rice cake. It is traditionally made with sun-dried leftover cooked white rice that is fried and coated with syrup. Etymology ''Ampáw'' ...

- Philippines **

Bhelpuri Bhelpuri is a savoury snack originating from India, and is also a type of chaat. It is made of puffed rice, vegetables and a tangy tamarind sauce, and has a crunchy texture. Bhel is often identified as a 'beach snack', strongly associated wit ...

- Indian subcontinent ** Muri - Indian subcontinent **

Puffed rice Puffed rice and popped rice (or pop rice) are types of puffed grain made from rice commonly eaten in the traditional cuisines of Southeast Asia, East Asia, and South Asia. It has also been produced commercially in the West since 1904 and is popu ...

(i.e. Rise Krispies ** Toffee Crisp - sweet made by Nestlé *

Wheat Wheat is a grass widely cultivated for its seed, a cereal grain that is a worldwide staple food. The many species of wheat together make up the genus ''Triticum'' ; the most widely grown is common wheat (''T. aestivum''). The archaeologi ...

** Golden Crisp, Honey Smacks USA - breakfast cereal **

Sugar Puffs Honey Monster Puffs are a honey-flavoured breakfast cereal made from sugar-coated wheat sold in the United Kingdom. The cereal was originally sold as Sugar Puffs, but was re-branded in 2014. It was labeled as Honey Monster Sugar Puffs for a t ...

UK - breakfast cereal *Other **

Yeot-gangjeong ''Yeot-gangjeong'' () is a candy bar-like variety of '' hangwa'' (traditional Korean confection) consisting of toasted seeds, nuts, beans, or puffed grains mixed with ''mullyeot'' (rice syrup). In general households, they usually make and e ...

- Korea ** Rainbow Drops UK - puffed maize and rice sweets **Maná - Peru - Puffed pasta, corn, or wheat kernels **Moong dal - puffed

mung beans The mung bean (''Vigna radiata''), alternatively known as the green gram, maash ( fa, ماش٫ )٫ mūng (), monggo, or munggo (Philippines), is a plant species in the legume family.Brief Introduction of Mung Bean. Vigna Radiata Extract G ...

Puffed dough foods

Corn puff Puffcorn or corn puffs are puffed or extruded corn snacks made with corn meal, and baked. Puffcorn is an extruded puffed corn snack which belongs in the snack group products made with corn grits, rice, wheat, or other cereals. Puffcorn is oft ...

** Cheese puffs (corn) **

Kix (cereal) Kix (stylized as KiX) is an American brand of breakfast cereal introduced in 1937 by the General Mills company of Golden Valley, Minnesota. The product is an extruded, expanded puffed-grain cereal made with cornmeal. Products General Mill ...

References

External links

{{Commons category, Puffed grains
Research notebooks and papers
of the inventor of the process of puffing rice and starches, Alexander P. Anderson, are available for research at th
Minnesota Historical Society
Breakfast cereals Dried foods Food technology Articles containing video clips Rice crackers it:Riso soffiato zh:米香