
Nori is a dried
edible seaweed
Edible seaweed, or sea vegetables, are seaweeds that can be eaten and used for culinary purposes. They typically contain high amounts of fiber. They may belong to one of several groups of multicellular algae: the red algae, green algae, and br ...
used in Japanese cuisine, made from species of the
red algae genus ''
Pyropia'', including ''P. yezonesis'' and ''
P. tenera''. It has a strong and distinctive flavor, and is often used to wrap rolls of
sushi
is a Japanese dish of prepared , usually with some sugar and salt, accompanied by a variety of , such as seafood, often raw, and vegetables. Styles of sushi and its presentation vary widely, but the one key ingredient is "sushi rice," also ...
or ''
onigiri
, also known as , , or rice ball, is a Japanese food made from white rice formed into triangular or cylindrical shapes and often wrapped in ''nori''. Traditionally, an onigiri is filled with pickled ume ('' umeboshi''), salted salmon, kats ...
'' (rice balls).
The finished dried sheets are made by a shredding and rack-drying process that resembles
papermaking
Papermaking is the manufacture of paper and cardboard, which are used widely for printing, writing, and packaging, among many other purposes. Today almost all paper is made using industrial machinery, while handmade paper survives as a speciali ...
. They are sold in packs in grocery stores for culinary purposes. Since nori sheets easily absorb water from the air and degrade, a
desiccant is needed when storing nori for any significant time.
History

Originally, the term ''nori'' was generic and referred to
seaweed
Seaweed, or macroalgae, refers to thousands of species of macroscopic, multicellular, marine algae. The term includes some types of ''Rhodophyta'' (red), ''Phaeophyta'' (brown) and ''Chlorophyta'' (green) macroalgae. Seaweed species such as ke ...
s, including ''
hijiki''. One of the earliest descriptions of nori is dated to around the eighth century. In the
Taihō Code
The was an administrative reorganisation enacted in 703 in Japan, at the end of the Asuka period. It was historically one of the . It was compiled at the direction of Prince Osakabe, Fujiwara no Fuhito and Awata no Mahito. Nussbaum, Louis ...
that was enacted in 701, ''nori'' already was included in the form of taxation. Local people were described as drying nori in
Hitachi Province
was an old province of Japan in the area of Ibaraki Prefecture. Nussbaum, Louis-Frédéric. (2005). "''Hitachi fudoki''" in . It was sometimes called . Hitachi Province bordered on Shimōsa (Lower Fusa), Shimotsuke, and Mutsu ( Iwase - ...
fudoki
are ancient reports on provincial culture, geography, and oral tradition presented to the reigning monarchs of Japan, also known as local gazetteers. They contain agricultural, geographical, and historical records as well as mythology and ...
(721–721), and harvesting of nori was mentioned in
Izumo Province
was an old province of Japan which today consists of the eastern part of Shimane Prefecture. It was sometimes called . The province is in the Chūgoku region.
History
During the early Kofun period (3rd century) this region was independent a ...
fudoki (713–733), showing that nori was used as food from ancient times. In ''
Utsubo Monogatari'', written around 987, ''nori'' was recognized as a common food. Nori had been consumed as paste form until the sheet form (Ita-nori 板海苔) was invented in
Asakusa
is a district in Taitō, Tokyo, Japan. It is known as the location of the Sensō-ji, a Buddhist temple dedicated to the bodhisattva Kannon. There are several other temples in Asakusa, as well as various festivals, such as the .
History
T ...
,
Edo
Edo ( ja, , , "bay-entrance" or "estuary"), also romanized as Jedo, Yedo or Yeddo, is the former name of Tokyo.
Edo, formerly a ''jōkamachi'' (castle town) centered on Edo Castle located in Musashi Province, became the ''de facto'' capital of ...
(contemporary Tokyo), around 1750 in the
Edo period
The or is the period between 1603 and 1867 in the history of Japan, when Japan was under the rule of the Tokugawa shogunate and the country's 300 regional ''daimyo''. Emerging from the chaos of the Sengoku period, the Edo period was character ...
through the method of
Japanese paper-making.
The word "''nori''" first appeared in an English-language publication in ''C. P. Thunberg's Trav.'', published in 1796.
It was used in conjugation as "''Awa nori''", probably referring to what now is called
aonori.
[
When Japan was in need of high food production after ]WWII
World War II or the Second World War, often abbreviated as WWII or WW2, was a world war that lasted from 1939 to 1945. It involved the World War II by country, vast majority of the world's countries—including all of the great power ...
, production of nori was in decline. They sought to supplement their traditional reliance upon harvesting the natural product from the sea. Due to a lack of understanding of nori's three-stage life cycle, however, those attempting to produce nori artificially did not understand why their cultivation methods were not being productive with nori. The industry was rescued by knowledge derived from the work of British phycologist Kathleen Mary Drew-Baker
Kathleen Mary Drew-Baker (6 November 1901 – 14 September 1957) was a British phycologist, known for her research on the edible seaweed '' Porphyra laciniata'' (nori), which led to a breakthrough for commercial cultivation.
Kathleen Drew-Ba ...
, who had been researching the organism ''Porphyria umbilicalis'' that grew in the seas around Wales and was harvested for food ( bara lafwr or bara lawr), as in Japan. Her work was discovered by Japanese scientists who applied it to artificial methods of seeding and growing the nori, rescuing the industry. Kathleen Baker was hailed in Japan as the "Mother of the Sea" and a statue was erected in her memory. She is still revered as the savior of the Japanese nori industry.
In the twenty-first century, the Japanese nori industry faces a new decline due to increased competition from seaweed producers in China and Korea and an increase in domestic sales tax.
The word ''nori'' started to be used widely in the United States and the product (imported in dry form from Japan) became widely available at natural food stores and Asian-American grocery stores in the 1960s due to the macrobiotic movement and in the 1970s with the increase of sushi bars and Japanese restaurants.
Production
Production and processing of ''nori'' is an advanced form of agriculture. The biology of ''Pyropia'', although complicated, now is well understood, and this knowledge is used to control the production process. Farming takes place in the sea where the ''Pyropia'' plants grow attached to nets suspended at the sea surface and where the farmers operate from boats. The plants grow rapidly, requiring approximately 45 days from "seeding" until the first harvest. Multiple harvests can be taken from a single seeding, typically at approximately ten-day intervals. Harvesting is accomplished using mechanical harvesters of a variety of configurations. Processing of raw product is mostly accomplished by highly automated machines that accurately duplicate traditional manual processing steps, but with much improved efficiency and consistency. The final product is a paper-thin, black, dried sheet of approximately and in weight.
Several grades of nori are available in the United States. The most common (and least expensive) grades are imported from China, costing approximately six cents per sheet. At the high end, ranging up to 90 cents per sheet, are "delicate ''shin-nori''" (''nori'' from the first of the year's several harvests) cultivated in the Ariake Sea, off the island of Kyushu in Japan.
In Japan, more than of coastal waters are given to producing of nori, worth more than a billion dollars. China produces approximately a third of this amount.
Culinary uses
Nori is commonly used as a wrap for sushi
is a Japanese dish of prepared , usually with some sugar and salt, accompanied by a variety of , such as seafood, often raw, and vegetables. Styles of sushi and its presentation vary widely, but the one key ingredient is "sushi rice," also ...
and ''onigiri
, also known as , , or rice ball, is a Japanese food made from white rice formed into triangular or cylindrical shapes and often wrapped in ''nori''. Traditionally, an onigiri is filled with pickled ume ('' umeboshi''), salted salmon, kats ...
''. It is also a garnish or flavoring in noodle preparations and soups. It is most typically toasted prior to consumption (''yaki-nori''). A common secondary product is toasted and flavored nori (''ajitsuke-nori''), in which a flavoring mixture (variable, but typically soy sauce, sugar, sake
Sake, also spelled saké ( ; also referred to as Japanese rice wine), is an alcoholic beverage of Japanese origin made by fermenting rice that has been polished to remove the bran. Despite the name ''Japanese rice wine'', sake, and ind ...
, mirin
is a type of rice wine and a common ingredient in Japanese cooking. It is similar to sake but with a lower alcohol content and higher sugar content. The sugar content is a complex carbohydrate that forms naturally during the fermentation pro ...
, and seasonings) is applied in combination with the toasting process. Nori also is eaten by making it into a soy sauce-flavored paste, ''nori no tsukudani'' (). Sometimes it also is used as a form of food decoration
Food presentation is the art of modifying, processing, arranging, or decorating food to enhance its aesthetic appeal.
The visual presentation of foods is often considered by chefs at many different stages of food preparation, from the manner ...
.
A related product, prepared from the unrelated green algae
The green algae (singular: green alga) are a group consisting of the Prasinodermophyta and its unnamed sister which contains the Chlorophyta and Charophyta/ Streptophyta. The land plants ( Embryophytes) have emerged deep in the Charophyte alg ...
''Monostroma'' and ''Enteromorpha'', is called '' aonori'' ( literally blue/green ''nori'') and it is used as an herb
In general use, herbs are a widely distributed and widespread group of plants, excluding vegetables and other plants consumed for macronutrients, with savory or aromatic properties that are used for flavoring and garnishing food, for medicina ...
on everyday meals, such as '' okonomiyaki'' and ''yakisoba
''Yakisoba'' ( ja, 焼きそば ), "fried noodle", is a Japanese noodle stir-fried dish. Usually, soba noodles are made from buckwheat flour, but soba in yakisoba are Chinese noodles (Chuuka soba) made from wheat flour, typically flavored wi ...
''.
Nutrition
Raw seaweed is 85% water, 6% protein
Proteins are large biomolecules and macromolecules that comprise one or more long chains of amino acid residues. Proteins perform a vast array of functions within organisms, including catalysing metabolic reactions, DNA replication, respon ...
, 5% carbohydrate
In organic chemistry, a carbohydrate () is a biomolecule consisting of carbon (C), hydrogen (H) and oxygen (O) atoms, usually with a hydrogen–oxygen atom ratio of 2:1 (as in water) and thus with the empirical formula (where ''m'' may or ...
s, and has negligible fat (table). In a 100 gram reference amount, seaweed is a rich source (20% or more of the Daily Value
The Reference Daily Intake (RDI) used in nutrition labeling on food and dietary supplement products in the U.S. and Canada is the daily intake level of a nutrient that is considered to be sufficient to meet the requirements of 97–98% of health ...
, DV) of vitamin A
Vitamin A is a fat-soluble vitamin and an essential nutrient for humans. It is a group of organic compounds that includes retinol, retinal (also known as retinaldehyde), retinoic acid, and several provitamin A carotenoids (most notably ...
, vitamin C
Vitamin C (also known as ascorbic acid and ascorbate) is a water-soluble vitamin found in citrus and other fruits and vegetables, also sold as a dietary supplement and as a topical 'serum' ingredient to treat melasma (dark pigment spots) a ...
, riboflavin
Riboflavin, also known as vitamin B2, is a vitamin found in food and sold as a dietary supplement. It is essential to the formation of two major coenzymes, flavin mononucleotide and flavin adenine dinucleotide. These coenzymes are involved in e ...
, and folate
Folate, also known as vitamin B9 and folacin, is one of the B vitamins. Manufactured folic acid, which is converted into folate by the body, is used as a dietary supplement and in food fortification as it is more stable during processing and ...
(table). Seaweed is a moderate source (less than 20% DV) of niacin, iron
Iron () is a chemical element with symbol Fe (from la, ferrum) and atomic number 26. It is a metal that belongs to the first transition series and group 8 of the periodic table. It is, by mass, the most common element on Earth, right in ...
, and zinc
Zinc is a chemical element with the symbol Zn and atomic number 30. Zinc is a slightly brittle metal at room temperature and has a shiny-greyish appearance when oxidation is removed. It is the first element in group 12 (IIB) of the periodic t ...
. Seaweed has a high content of iodine
Iodine is a chemical element with the Symbol (chemistry), symbol I and atomic number 53. The heaviest of the stable halogens, it exists as a semi-lustrous, non-metallic solid at standard conditions that melts to form a deep violet liquid at , ...
, providing a substantial amount in just one gram. A 2014 study reported that dried purple laver ("nori") contains vitamin B12 in sufficient quantities to meet the RDA RDA may refer to:
Organisations
* Rassemblement Démocratique Africain (African Democratic Rally), a political party formed in 1946 in French West Africa.
* Rawalpindi Development Authority, Pakistan.
* Reader's Digest Association, a magazine publ ...
requirement (Vitamin B12 content: 77.6 μg /100 g dry weight). By contrast, however, a 2017 review concluded that vitamin B12 may be destroyed during metabolism
Metabolism (, from el, μεταβολή ''metabolē'', "change") is the set of life-sustaining chemical reactions in organisms. The three main functions of metabolism are: the conversion of the energy in food to energy available to run c ...
or is converted into inactive B12 analogs
Analog or analogue may refer to:
Computing and electronics
* Analog signal, in which information is encoded in a continuous variable
** Analog device, an apparatus that operates on analog signals
*** Analog electronics, circuits which use analog ...
during drying and storage. The Academy of Nutrition and Dietetics
The Academy of Nutrition and Dietetics is a 501(c)(6) trade association in the United States. With over 112,000 members, the association claims to be the largest organization of food and nutrition professionals. It has Dietitian, registered dieti ...
stated in 2016 that nori is not an adequate source of vitamin B12 for humans.
Health risks
Nori may contain toxic metals (arsenic
Arsenic is a chemical element with the symbol As and atomic number 33. Arsenic occurs in many minerals, usually in combination with sulfur and metals, but also as a pure elemental crystal. Arsenic is a metalloid. It has various allotropes, bu ...
and cadmium
Cadmium is a chemical element with the symbol Cd and atomic number 48. This soft, silvery-white metal is chemically similar to the two other stable metals in group 12, zinc and mercury. Like zinc, it demonstrates oxidation state +2 in most of ...
), whose levels are highly variable among nori products. It also contains amphipod allergens that may cause serious allergic reactions, especially in highly sensitized crustacean-allergic people. Therefore, daily consumption of high amounts of dried nori is discouraged.
Similar food
The red algae genera is also consumed in Korean cuisine as '' gim'' and in Wales
Wales ( cy, Cymru ) is a Countries of the United Kingdom, country that is part of the United Kingdom. It is bordered by England to the Wales–England border, east, the Irish Sea to the north and west, the Celtic Sea to the south west and the ...
and Ireland
Ireland ( ; ga, Éire ; Ulster Scots dialect, Ulster-Scots: ) is an island in the Atlantic Ocean, North Atlantic Ocean, in Northwestern Europe, north-western Europe. It is separated from Great Britain to its east by the North Channel (Grea ...
as laverbread.
See also
*
*
*
*
* , – river algae often eaten in sheets in Laos
*
* Porphyra
''Porphyra'' is a genus of coldwater seaweeds that grow in cold, shallow seawater. More specifically, it belongs to red algae phylum of laver species (from which comes laverbread), comprising approximately 70 species.Brodie, J.A. and Irvine ...
References
External links
Suria Link Seaplants Handbook
Description and images of cultivation and harvesting
Nori Dishes (w/video)
Marutoku Nori: About Nori
{{Authority control
Bangiophyceae
Edible seaweeds
Japanese cuisine
Japanese cuisine terms
Flora of Japan
Marine biota of Asia