Editing Water (section)

====Food processing====
[[File:Cuisson des pates.jpg|thumb|Water can be used to cook foods such as [[noodles]].]]
[[File:Sterilewater.jpg|thumb|upright|Sterile water for injection]]
[[Boiling]], [[steaming]], and [[simmering]] are popular cooking methods that often require immersing food in water or its gaseous state, steam.<ref>{{Cite book|url=https://books.google.com/books?id=xZHUAAAAMAAJ&pg=PA54|title=A Course in Household Arts: Part I|last=Duff|first=Loretto Basil|date=1916|publisher=Whitcomb & Barrows|access-date=3 December 2017|archive-date=14 April 2021|archive-url=https://web.archive.org/web/20210414164100/https://books.google.com/books?id=xZHUAAAAMAAJ&pg=PA54|url-status=live}}</ref> Water is also used for [[dishwashing]]. Water also plays many critical roles within the field of [[food science]].

[[Solutes]] such as salts and sugars found in water affect the physical properties of water. The boiling and freezing points of water are affected by solutes, as well as [[air pressure]], which is in turn affected by altitude. Water boils at lower temperatures with the lower air pressure that occurs at higher elevations. One [[mole (unit)|mole]] of sucrose (sugar) per kilogram of water raises the boiling point of water by {{convert|0.51|C-change|3}}, and one mole of salt per kg raises the boiling point by {{convert|1.02|C-change|3}}; similarly, increasing the number of dissolved particles lowers water's freezing point.<ref name="vaclacik">{{cite book |title=Essentials of Food Science |url=https://books.google.com/books?id=iCCsvwZrguUC |year=2007 |last1=Vaclavik |first1=Vickie A. |last2=Christian |first2=Elizabeth W. |publisher=Springer |isbn=978-0-387-69939-4 |access-date=31 August 2020 |archive-date=14 April 2021 |archive-url=https://web.archive.org/web/20210414164352/https://books.google.com/books?id=iCCsvwZrguUC |url-status=live }}</ref>

Solutes in water also affect water activity that affects many chemical reactions and the growth of microbes in food.<ref name="deman">{{cite book |url=https://books.google.com/books?id=kDYJ7a1HbD0C&pg=PA434 |title=Principles of Food Chemistry |year=1999 |last=DeMan |first=John M. |publisher=Springer |isbn=978-0-8342-1234-3 |access-date=31 August 2020 |archive-date=14 April 2021 |archive-url=https://web.archive.org/web/20210414185952/https://books.google.com/books?id=kDYJ7a1HbD0C&pg=PA434 |url-status=live }}</ref> Water activity can be described as a ratio of the vapor pressure of water in a solution to the vapor pressure of pure water.<ref name="vaclacik" /> Solutes in water lower water activity—this is important to know because most bacterial growth ceases at low levels of water activity.<ref name="deman" /> Not only does microbial growth affect the safety of food, but also the preservation and shelf life of food.

[[Water hardness]] is also a critical factor in food processing and may be altered or treated by using a chemical ion exchange system. It can dramatically affect the quality of a product, as well as playing a role in sanitation. Water hardness is classified based on concentration of calcium carbonate the water contains. Water is classified as soft if it contains less than 100&nbsp;mg/L (UK)<ref name="DEFRA">{{cite web |url=http://dwi.defra.gov.uk/consumers/advice-leaflets/hardness_map.pdf |title=Map showing the rate of hardness in mg/L as Calcium carbonate in England and Wales |publisher=[[Department for Environment, Food and Rural Affairs|DEFRA]] Drinking Water Inspectorate |date=2009 |access-date=18 May 2015 |archive-url=https://web.archive.org/web/20150529054911/http://dwi.defra.gov.uk/consumers/advice-leaflets/hardness_map.pdf |archive-date=29 May 2015 |url-status=live }}</ref> or less than 60&nbsp;mg/L (US).<ref name="USGS">{{cite web |url=https://water.usgs.gov/edu/hardness.html |publisher=US Geological Service |title=Water hardness |date=8 April 2014 |access-date=18 May 2015 |archive-url=https://web.archive.org/web/20150518204909/https://water.usgs.gov/edu/hardness.html |archive-date=18 May 2015 |url-status=live}}</ref>

According to a report published by the Water Footprint organization in 2010, a single kilogram of beef requires {{convert|15|e3L|e3impgal+e3usgal}} of water; however, the authors also make clear that this is a global average and circumstantial factors determine the amount of water used in beef production.<ref>{{cite report |title=The green, blue and grey water footprint of farm animals and animal products, Value of Water |series=Research Report Series |volume=1|issue=48 |url=http://www.waterfootprint.org/Reports/Report-48-WaterFootprint-AnimalProducts-Vol1.pdf |publisher=UNESCO – IHE Institute for Water Education |access-date=30 January 2014 |first1=M. M. |last1=Mekonnen |first2=A. Y. |last2=Hoekstra |date=December 2010 |archive-url=https://web.archive.org/web/20140527104135/http://www.waterfootprint.org/Reports/Report-48-WaterFootprint-AnimalProducts-Vol1.pdf |archive-date=27 May 2014 |url-status=live}}</ref>