Editing Pea (section)

== Uses ==

=== Nutrition ===
Raw green peas are 79% water, 14% [[carbohydrate]]s, 5% [[protein (nutrient)|protein]], and contain negligible [[fat]]. In a reference amount of {{convert|100|g|oz|abbr=off|frac=2}}, raw green peas supply {{convert|339|kJ|kcal|abbr=off}} of [[food energy]], and are a rich source (20% or more of the [[Daily Value]], DV) of [[vitamin C]] (48% DV), [[vitamin K]], [[thiamine]], and [[manganese]], with several [[B vitamins]] and [[dietary mineral]]s in moderate amounts (11–16% DV).

{{nutritionalvalue
| name = Peas, green, raw (fresh)
| image = (Pisum sativum), A pea is a most commonly green.JPG
| kJ = 339
| water = 79 g
| protein = 5.42 g
| fat = 0.4 g
| carbs = 14.45 g
| fiber = 5.1 g
| sugars = 5.67 g
| calcium_mg = 25
| iron_mg = 1.47
| magnesium_mg = 33
| phosphorus_mg = 108
| potassium_mg = 244
| sodium_mg = 5
| zinc_mg = 1.24
| manganese_mg = 0.41
| vitC_mg = 40
| thiamin_mg = 0.266
| riboflavin_mg = 0.132
| niacin_mg = 2.09
| vitB6_mg = 0.169
| folate_ug = 65
| vitA_ug = 38
| betacarotene_ug = 449
| lutein_ug = 2477
| vitE_mg = 0.13
| vitK_ug = 24.8
| source_usda = 1
| note = [https://fdc.nal.usda.gov/food-details/170419/nutrients Link to USDA Database entry]
}}

=== Culinary ===
In modern times peas are usually boiled or [[steamed]], which breaks down the cell walls and makes them taste sweeter and the nutrients more [[Bioavailability|bioavailable]]. Along with [[broad bean]]s and [[lentil]]s, these formed an important part of the diet of most people in the Middle East, North Africa and Europe during the [[Middle Ages]].<ref>{{Citation
|last1=Bianchini |first1=F. |last2=Corbetta |first2=F. |year=1976 |title=The Complete Book of Fruits and Vegetables |place=New York |publisher=Crown |isbn=978-0-517-52033-8 |page=40}}</ref> By the 17th and 18th centuries, it had become popular to eat peas "green", that is, while they are immature and right after they are picked.<ref>{{Citation|last=Hedrick |first=U.P. |year=1919 |chapter=Sturtevant's Notes on Edible Plants |title=Report of the New York Agricultural Experiment Station for the Year 1919 II |place=Albany |publisher=J.B Lyon Company, State Printers |chapter-url=http://food.oregonstate.edu/glossary/p/pplant189.html |access-date=Feb 26, 2010 |url-status=dead |archive-url=https://web.archive.org/web/20110718234523/http://food.oregonstate.edu/glossary/p/pplant189.html |archive-date=July 18, 2011 }}</ref> New cultivars of peas were developed by the English during this time, which became known as "garden" or "English" peas. The popularity of green peas spread to [[North America]]. [[Thomas Jefferson]] grew more than 30 cultivars of peas on his estate.<ref>{{Citation |last=Kafka |first=B. |year=2005 |title=Vegetable Love |place=New York |publisher=Artisan |isbn=978-1-57965-168-8 |page=[https://archive.org/details/vegetablelove00kafk/page/297 297] |url-access=registration |url=https://archive.org/details/vegetablelove00kafk/page/297 }}</ref> With the invention of canning, peas were one of the first vegetables to be canned.{{sfn|Bitting|1909|p=5}}

[[File:Chinese Chawal in Basmati.jpg|thumb|Peas in [[fried rice]]]]
Fresh peas are often eaten boiled and flavored with [[butter]] and/or [[spearmint]] as a side dish vegetable. Salt and pepper are also commonly added to peas when served. Fresh peas are also used in [[pot pie]]s, salads and [[casserole]]s. Pod peas ([[snow pea]]s and [[snap pea]]s) are used in stir-fried dishes, particularly those in [[American Chinese cuisine]].<ref>{{cite web|url=http://www.pccnaturalmarkets.com/health/Food_Guide/Snow_Peas.htm|title=Product how-to guides|work=PCC Natural Markets}}</ref> Pea pods do not keep well once picked, and if not used quickly, are best preserved by drying, [[canning]] or [[freezing]] within a few hours of harvest.<ref>{{citation |mode=cs1|contribution=Peas |title=Glossary: BBC Good Food |publisher=BBC |contribution-url=https://www.bbcgoodfood.com/glossary/peas |access-date=2019-07-25}}</ref>

Dried peas are often made into a [[soup]] or simply eaten on their own. In [[Japan]], [[China]], [[Taiwan]] and some [[Southeast Asia]]n countries, including [[Thailand]], the [[Philippines]] and [[Malaysia]], peas are roasted and salted, and eaten as [[snack]]s. In the Philippines, peas, while still in their pods, are a common ingredient in viands and [[pansit]]. In the UK, dried yellow or green split peas are used to make [[pease pudding]] (or "pease porridge"), a traditional dish. In North America, a similarly traditional dish is split [[pea soup]].<ref>{{cite web
| url = https://whatscookingamerica.net/soup/split-pea-soup.htm
| title = Classic Split Pea Soup History and Recipe
| last = Stradley
| first = Linda
| date = n.d.
| website = What's Cooking America
| publisher =
| access-date = 10 November 2023
| quote = }}</ref>

Pea soup is eaten in many other parts of the world, including [[northern Europe]], parts of [[middle Europe]], [[Russia]], [[Iran]], [[Iraq]] and [[India]].<ref>{{cite web|url=http://www.lansbladet.se/vasterbotten/tidningen/200803/pdf/18.pdf|archive-url=https://web.archive.org/web/20161229225644/http://www.lansbladet.se/vasterbotten/tidningen/200803/pdf/18.pdf|url-status=dead|archive-date=29 December 2016|title=lansbladet.se|date=29 December 2016|access-date=21 August 2017}}</ref>

In [[India]], fresh peas are used in various dishes such as ''[[aloo matar]]'' (curried potatoes with peas) or ''[[mattar paneer]]'' ([[paneer]] cheese with peas), though they can be substituted with frozen peas as well. Peas are also eaten raw, as they are sweet when fresh off the bush. Green peas known as hasiru batani in [[Kannada]] are used to make curry and gasi.<ref>{{cite web|url=https://udupi-recipes.com/2014/05/potato-pea-curry-batani-gasi-recipe-chapati-side-dish.html|title=Batani Gasi Recipe|date=19 May 2014|access-date=2 May 2020}}</ref> Split peas are also used to make ''[[dal]]'', particularly in [[Guyana]], and [[Trinidad]], where there is a significant population of [[Indian people|Indians]].{{Citation needed|date=March 2017}}

In [[Chinese cuisine]], the tender new growth [leaves and stem] {{Lang|zh-latn|dou miao}} ([[:zh:豆苗|豆苗]]; {{Lang|zh-latn|dòu miáo}}) are commonly used in stir-fries. Much like picking the leaves for tea, the farmers pick the tips off of the pea plant.{{Citation needed|date=March 2017}}

In [[Greece]], [[Tunisia]], [[Turkey]], [[Cyprus]], and other parts of the Mediterranean, peas are made into a stew with lamb and potatoes.{{Citation needed|date=March 2017}}

In [[Hungary]] and [[Serbia]], pea soup is often served with [[dumpling]]s and spiced with hot [[paprika]].<ref name="hung_Gree">{{Cite web |title=Green Pea Soup, Hungarian - Soups - Recipes |last=László |first=Vida |work=hungarianpaprika.net |access-date=11 December 2019 |url= https://hungarianpaprika.net/en/recipes-page-10/soups-blogcat-2/green_pea_soup__hungarian-blog-3/}}</ref><ref name="hung_Hung">{{Cite web |title=Hungarian Pea Soup – Borsóleves |work=Hungarian Tidbits |date=15 September 2013 |access-date=11 December 2019 |url= https://www.hungariantidbits.com/hungarian-pea-soup-borsoleves/}}</ref><ref name="just_Hung">{{Cite web |title=Hungarian Pea Soup with Nokedli |work=Just a Taste |date=21 January 2009 |access-date=11 December 2019 |url= https://www.justataste.com/hungarian-pea-soup-with-nokedli/}}</ref>

In the United Kingdom, dried, rehydrated and mashed [[marrowfat peas]], or cooked green split peas, known as [[mushy peas]], are popular, originally in the north of England, but now ubiquitously, and especially as an accompaniment to [[fish and chips]] or [[meat pie]]s, particularly in [[fish and chip shop]]s. [[Sodium bicarbonate]] is sometimes added to soften the peas. In 2005, a poll of 2,000 people revealed the pea to be Britain's seventh favourite culinary vegetable.<ref>{{cite news| url=https://www.theguardian.com/uk/2005/may/23/britishidentity.foodanddrink | location=London | work=The Guardian | title=Onions come top for British palates | first=Martin | last=Wainwright | date=2005-05-23}}</ref>

Processed peas are mature peas which have been dried, soaked and then heat treated (processed) to prevent spoilage—in the same manner as [[Pasteurization|pasteurizing]]. Cooked peas are sometimes sold dried and coated with [[wasabi]], [[salt]], or other spices.<ref>{{cite web |url=http://www.hesca.org/nutrition/are-wasabi-peas-good-for-you/ |title=Are Wasabi Peas Good For You |last=Enders |first=Missy |website=The Healthy & Smart Choice Advocates |publisher=HESCA |access-date=June 24, 2018 |date=2016-10-03 |archive-date=6 August 2020 |archive-url=https://web.archive.org/web/20200806072436/http://www.hesca.org/nutrition/are-wasabi-peas-good-for-you/ |url-status=dead }}</ref>

In North America [[pea milk]] is produced and sold as an alternative to [[cow milk]] for a variety of reasons.<ref>{{cite web|url=https://www.gq.com/story/what-is-pea-milk|title=If You Like Almond Milk, You'll Love...Pea Milk?|last=Vrabel|first=Jeff|date=2016-07-10|access-date=2016-07-13}}</ref>

<gallery mode="packed" widths="150px" heights="150px">
File:Wasabi peas - Massachusetts.jpg|[[Wasabi]] peas
File:Fish and chips at Sainsbury's Low Hall, Chingford, London.jpg|[[Fish and chips]] with peas
File:Pea soup 2.jpg|[[Pea soup]]
File:Aloo Matar.JPG|[[Aloo mutter]]
File:Matar Panir mit Chapati - Mutter Paneer with chapati.jpg|[[Matar paneer]] with [[chapati]]
</gallery>

=== Pea sprouts ===
[[File:Dao miao, snow pea shoots-sprouts.jpg|thumb|Pea sprouts]]
In East Asia, pea sprouts or shoots ({{lang|zh|豆苗}}; {{lang|ko|완두순}})<ref>{{cite web |url=http://www.fooddb.com.hk/chi_fruit.php?id=15&type=1 |work=香港食物規格資料庫網站 |title=莖葉類蔬菜: 豆苗 |trans-title=Stem and Leaves Vegetables: Pea Sprouts |access-date=2021-03-05 |language=zh-hant |archive-date=4 August 2011 |archive-url=https://web.archive.org/web/20110804133755/http://www.fooddb.com.hk/chi_fruit.php?id=15&type=1 |url-status=dead }}</ref> were once dedicated cuisine{{Clarify|reason=what does dedicated mean here?|date=January 2024}} when the plant was less highly available. Today, when the plant can be easily grown, fresh pea shoots are available in supermarkets or may be grown at home.

=== Manufacturing ===
==== Frozen peas ====
[[File:Frozen peas.JPG|right|thumb|Frozen green peas]]

In order to freeze and preserve peas, they must first be grown, picked, and shelled. Usually, the more tender the peas are, the more likely that they will be used in the final product. The peas must be put through the process of freezing shortly after being picked so that they do not spoil too soon. Once the peas have been selected, they are placed in ice water and allowed to cool. After, they are sprayed with water to remove any residual dirt or dust that may remain on them. The next step is [[blanching (cooking)|blanching]]. The peas are boiled for a few minutes to remove any enzymes that may shorten their shelf life. They are then cooled and removed from the water. The final step is the actual freezing to produce the final product.<ref>{{cite web|url=http://www.madehow.com/Volume-5/Frozen-Vegetable.html|title=How frozen vegetable is made - production process, making, used, processing, product, industry, machine|work=madehow.com}}</ref> This step may vary considerably; some companies freeze their peas by air blast freezing, where the vegetables are put through a tunnel at high speeds and frozen by cold air. Finally, the peas are packaged and shipped out for retail sale.

=== Science ===
In the mid-19th century, Austrian monk [[Gregor Mendel]]'s observations of pea pods led to the principles of [[Mendelian genetics]], the foundation of modern [[genetics]].<ref>{{cite journal|author=Nasmyth, K |title=The magic and meaning of Mendel's miracle|journal=Nat Rev Genet|volume=23|pages=447–452|year=2022|issue=7 |doi=10.1038/s41576-022-00497-2|pmid=35595848 }}</ref><ref>{{cite journal|url=http://courses.pbsci.ucsc.edu/mcdb/bio105/Spring15/Lecture2/Rediscovery%20of%20Mendel.pdf|title=The "Rediscovery" of Mendel's Work |publisher=General College, University of Minnesota|journal=Bioscene|volume=27|number=2|date=May 2001|first=Randy|last=Moore|archive-url=https://web.archive.org/web/20160216153032/http://courses.pbsci.ucsc.edu/mcdb/bio105/Spring15/Lecture2/Rediscovery%20of%20Mendel.pdf |archive-date=16 February 2016 }}</ref> He ended up growing and examining about 28,000 pea plants in the course of his experiments.<ref name=h2g2>{{cite web|url=http://h2g2.com/dna/h2g2/A6257865|title=h2g2 - The Garden Pea - Edited Entry|first=Not Panicking|last=Ltd|website=H2g2.com|date=December 2005 |access-date=21 August 2017}}</ref>

Mendel chose peas for his experiments because he could grow them easily, pure-bred strains were readily available,<ref>{{cite journal|author=Ellis, T.H.N.|author2= Hofer, J.M.I.|author3= Swain, M.T.|author4= Van Dijk, P.J.|title= Mendel's pea crosses: varieties, traits and statistics|journal=Hereditas|volume=156|issue=33 |year=2019|page= 33|doi=10.1186/s41065-019-0111-y|doi-access= free|pmid= 31695583|pmc= 6823958}}</ref> and the structure of the flowers protect them from cross-pollination, and cross pollination was easy.<ref>{{cite web | url=http://www.esp.org/foundations/genetics/classical/browse/ | title=ESP Classical Genetics }}</ref> Mendel cross-bred tall and dwarf pea plants, green and [[yellow pea]]s, purple and white flowers, wrinkled and smooth peas, and a few other traits. He then observed the resulting offspring. In each of these cases, one trait is dominant and all the offspring, or Filial-1 (abbreviated F<sub>1</sub>) generation, showed the dominant trait. Then he allowed the F<sub>1</sub> generation to self pollinate and observed their offspring, the Filial-2 (abbreviated F<sub>2</sub>)  generation. The F<sub>2</sub> plants had the dominant trait in approximately a 3:1 ratio. He studied later generations of self pollinated plants, and performed crosses to determine the nature of the pollen and egg cells.<ref>{{cite web|title=Experiments in Plant Hybridization|year=1865|author=
Gregor Mendel|url=http://www.esp.org/foundations/genetics/classical/gm-65-a.pdf}}</ref>

Mendel reasoned that each parent had a 'vote' in the appearance of the offspring, and the non-dominant, or [[Dominance (genetics)|recessive]], trait appeared only when it was inherited from both parents. He did further experiments that showed each trait is separately inherited. Unwittingly, Mendel had solved a major problem with [[Charles Darwin]]'s [[theory of evolution]]: how new traits were preserved and not blended back into the population, a question Darwin himself did not answer. Mendel's work was published in an obscure Austrian journal and was not rediscovered until about 1900.<ref name=mendel>{{cite web|url=http://naturalselection.0catch.com/Files/gregormendel.html|title=Gregor Mendel - Father of Genetics|website=naturalselection.0catch.com|access-date=21 August 2017|archive-date=5 September 2017|archive-url=https://web.archive.org/web/20170905152043/http://naturalselection.0catch.com/Files/gregormendel.html|url-status=dead}}</ref>

=== Nitrogen fixation ===
[[File:Snow pea flowers.jpg|thumb|upright|Pea flowers]]
Peas, like many legumes, contain [[symbiosis|symbiotic]] bacteria called ''[[Rhizobia]]'' within [[root nodule]]s of their [[root|root systems]]. These bacteria have the special ability to [[nitrogen fixation|fix nitrogen]] from atmospheric, molecular nitrogen ({{chem2|N2}}) into [[ammonia]] ({{chem2|NH3}}).<ref>{{cite web|url=http://www.biology.ed.ac.uk/archive/jdeacon/microbes/nitrogen.htm|title=Biological Sciences|website=Biology.ed.ac.uk|access-date=21 August 2017|archive-date=16 January 2013|archive-url=https://web.archive.org/web/20130116214211/http://www.biology.ed.ac.uk/archive/jdeacon/microbes/nitrogen.htm|url-status=dead}}</ref> The chemical reaction is:
:{{chem2|N2 + 8H+ + 8e- -> 2NH3 + H2}}
Ammonia is then converted to another form, [[ammonium]] ({{chem2|NH4+}}), usable by (some) plants by the following reaction:
:{{chem2|NH3 + H+ -> NH4+}}
The root nodules of peas and other legumes are sources of nitrogen that they can use to make [[amino acid]]s, constituents of proteins. Hence, legumes are good sources of [[plant protein]].<ref>{{Cite journal|last1=Lawrence|first1=John M.|last2=Grant|first2=D. R.|date=September 1963|title=Nitrogen Mobilization in Pea Seedlings. II. Free Amino Acids|journal=Plant Physiology|volume=38|issue=5|pages=561–566|issn=0032-0889|pmid=16655833|pmc=549973|doi=10.1104/pp.38.5.561}}</ref>

When a pea plant dies in the field, for example following the [[harvest]], all of its remaining nitrogen, incorporated into [[amino acid]]s inside the remaining plant parts, is released back into the [[soil]]. In the soil, the amino acids are converted to nitrate ({{chem2|NO3-}}), that is available to other plants, thereby serving as fertilizer for future crops.<ref>Postgate, J (1998). Nitrogen Fixation, 3rd Edition. Cambridge University Press, Cambridge UK</ref><ref>{{Cite book |author=Smil, V |year=2000 |title=Cycles of Life |publisher=Scientific American Library}}</ref>