Sushi is a Japanese food consisting
of cooked vinegared rice (shari) combined with other
ingredients (neta). Neta and forms of sushi presentation
vary, but the ingredient which all sushi have in
common is shari. The most common neta is seafood.
Raw meat sliced and served by itself is sashimi.
The original type of sushi, known today as nare-zushi,
was first developed in Southeast Asia, and spread
to south China before introduction to Japan. The
term sushi comes from an archaic grammatical form
no longer used in other contexts; literally, sushi
means "sour-tasting", a reflection of
its historic fermented roots. The oldest form of
sushi in Japan, narezushi, still very closely resembles
this process, wherein fish is fermented via being
wrapped in soured fermenting rice. The fish proteins
break down via fermentation into its constituent
amino acids. The fermenting rice and fish results
in a sour taste and also one of the five basic tastes,
called umami in Japanese. In Japan, narezushi evolved
into oshizushi and ultimately Edomae nigirizushi,
which is what the world today knows as "sushi".
Contemporary Japanese sushi has little resemblance
to the traditional lacto-fermented rice dish. Originally,
when the fermented fish was taken out of the rice,
only the fish was consumed and the fermented rice
was discarded. The strong-tasting and smelling funazushi,
a kind of narezushi made near Lake Biwa in Japan,
resembles the traditional fermented dish. Beginning
in the Muromachi period (AD 1336–1573) of
Japan, vinegar was added to the mixture for better
taste and preservation. The vinegar accentuated
the rice's sourness and was known to increase its
shelf life, allowing the fermentation process to
be shortened and eventually abandoned. In the following
centuries, sushi in Osaka evolved into oshi-zushi.
The seafood and rice were pressed using wooden (usually
bamboo) molds. By the mid 18th century, this form
of sushi had reached Edo (contemporary Tokyo).
The contemporary version, internationally known
as "sushi", was created by Hanaya Yohei
(1799–1858) at the end of the Edo period in
Edo. The sushi invented by Hanaya was an early form
of fast food that was not fermented (therefore prepared
quickly) and could be eaten with one's hands at
a roadside or in a theatre. Originally, this sushi
was known as Edomae zushi because it used freshly
caught fish in the Edo-mae (Edo Bay or Tokyo Bay).
Though the fish used in modern sushi no longer usually
comes from Tokyo Bay, it is still formally known
as Edomae nigirizushi.