includes ancient puffed grains like popcorn
as well as puffed rice
. Modern puffed grains are often created using high temperature, pressure, and/or extrusion
Ingredients for puffed rice can be as simple as rice and perhaps salt
for taste. Other products like Rice Krispies
, Corn Flakes
, or Corn Pops
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 are popular as breakfast cereals
and in the form of "rice cakes
". While it is easy to recognize that the cereals came from whole grains, the expansion factor for rice cakes is even greater, and the final product is somewhat more homogeneous
High pressure puffed grain is created by placing whole grains under high pressure
. When the containment vessel's seal is suddenly broken, the entrained steam then flash
and bloats the endosperm
of the kernel
, increasing its volume to many times its original size.
Puffed rice or other grains are occasionally found as street food in China
(called "ppeong twigi"
뻥튀기), and Japan
(called "pong gashi" ポン菓子
), where peddlers implement the puffing process using an integrated pushcart/puffer featuring a rotating steel pressure chamber
heated over an open flame. The great booming sound produced by the release of pressure serves as advertising to attract customers.