View source for Spile

{{Short description|Peg used to control airflow in casks of ale}}
{{cleanup rewrite|date=November 2023}}
{{about||the riverbank erosion prevention technique|spiling}}
[[File:Lwów - barrels.JPG|Various beer barrels with wooden spiles (round knobs on cask) in addition to [[beer tap]]s.|thumb]]
A '''spile''' (sometimes called a "cask peg") is a [[wood]]en or [[metal]] peg used to control the flow of air into, and [[carbon dioxide]] out of, a [[cask]] of [[ale]] or [[wine]].<ref>{{Cite web|url=https://www.carlingpartnership.com/insights/back-to-the-pub-getting-the-perfect-pint-of-cask-ale/|title=Back To The Pub – Getting The Perfect Pint Of Cask Ale|first=the carling|last=team|date=August 2, 2021}}</ref><ref>On Making Wines from Fruits of Native Growth. The Dublin Penny Journal, vol. 2, no. 60, 1833, pp. 62–62. JSTOR, http://www.jstor.org/stable/30003126. Accessed 6 Nov. 2023.</ref> Spiles can also be used to broach liquids (like [[maple syrup]]) from a [[tree]].<ref name="sugar">{{cite journal |url=https://books.google.com/books?id=uzcZAQAAIAAJ&q=%22Spile%22&pg=PA241 |title=Producing Sugar at Home |last=Thatcher |first=R.W. |journal=Minnesota Farmers' Institute Annual |year=1917 |volume=30 |page=241 }}</ref>

==Ale use==
[[Cask ale]] is dispensed without the addition of externally supplied gas. Properly conditioned cask ale will have enough dissolved carbon dioxide (produced by yeast) to have bubbles.{{cref|1}} In fact, the yeast can produce more carbon dioxide than is required, and it is for this reason that the cask is vented through the hole in the [[shive]].

The cask is sealed when it is first connected to a [[beer engine]]. It has a keystone (where the [[beer tap]] will be driven in) and a shive (through which it was filled). Once it has been laid down for dispensing, a venting punch is used to pierce the shive, which is either partially pre-drilled or has a hardwood tutt{{typo help inline|reason=similar to tuft|date=August 2020}} sealing the completely drilled hole. This breaks the seal, and the tap can then be driven into the keystone.

To allow the loss of excess gas, a soft spile (made of open-grained [[softwood]], [[bamboo]], or harder wood with cuts in) is used.<ref>{{Cite web|url=https://epgp.inflibnet.ac.in/epgpdata/uploads/epgp_content/S001827/P001835/M029506/ET/15246356335.35Q1.pdf|title=Paper 05: Food and Beverage Service Operations and Management}}</ref> Once a [[cellarman]] judges this process to be complete, a hard spile is inserted which does not allow any more gas out. These are made of harder wood (usually still technically "softwood", but denser and more solid than a soft spile). When beer is being drawn from the cask a hard spile is removed and can be replaced by a soft spile, or left open. When no beer is being dispensed a hard spile is put back in. Plastic spiles are also available.

Once a spile is reinserted, enough gas will be generated by the yeast to replace the volume of gas that will have come out of solution. But the amount of carbon dioxide that can be produced is limited, so a hard spile is kept in as much as possible. This is one of the reasons for real ale's short shelf-life once a cask is opened – if too much carbon dioxide is lost, the beer will become flat. Typically, the beer will be good only for two to four days{{cref|2}}; this short shelf life is why it is important that a [[pub]] serving real ale have sufficient turnover for casks to be emptied while still at their best.

== Other uses for term ==
[[File:Mother Nature's candy (8549560048).jpg|A [[spigot]] (or "spile") extracting syrup from a maple tree.|thumb]]
Like many such older terms, the word spile has other local meanings. For example:
* A wooden stake or [[fence]] post.
* A tapper,<ref>{{cite web |url=https://www.horniman.ac.uk/search?s=Tapper |title=Tappers |work=Horniman Museum and Gardens |location=London |access-date=2021-04-09 |archiveurl=https://web.archive.org/web/20210409233736/https://www.horniman.ac.uk/search?s=Tapper |archivedate=2021-04-09 |publisher=Department for Digital, Culture, Media and Sport }}</ref> an implement used to tap any sort of tree (e.g., for [[birch sap]], [[maple syrup]], [[rubber tapping]], or [[palm wine]] from a [[toddy palm]]).
** An iron or wood [[spigot]] driven into a sugar maple to produce [[maple syrup]].<ref name="maple_syrup">{{cite web |url=http://www.goodeatsfanpage.com/Season3/Pancakes/PancakesTranscript.htm |work=Good Eats Fan Page |title=Flap Jack Do It Again Transcript |date=2006-05-21 }}</ref><ref name="sugar"/>
* At [[Indian Harbour, Nova Scotia|Indian Harbour]] in Nova Scotia, the shores on which fish processing "stores" were located were called spiles.{{cn|date=November 2023}}
* A term used in boatbuilding to describe the means/actions which a builder uses to determine the shape of any curved piece needing to be fitted to a curved surface.{{cn|date=November 2023}}

==In popular culture==
A spile is utilized to obtain water in the novel ''[[Catching Fire]]'' (2009) and subsequent film ''[[The Hunger Games: Catching Fire]]'' (2013).{{fact|date=October 2022}}

The spile consists of a tube with one end sharpened and the other split. When pounded into a tree, a stream of fresh water flows from the tube. Most of the year, this is not consistent with the nature of trees, as water diffuses upward through very tiny [[capillary]] passages. When a tree is cut down, water does not flow out of the cut surface. The technique used in the movie would only work in early spring or late winter, when the watery sap runs high in the trees.{{fact|date=October 2022}}

The taps that are placed in maple trees are placed into drilled holes and the resultant fluid is sap, not water.{{fact|date=October 2022}}

==See also==
* [[Beer tap]]
* [[Cask breather]]
* [[Stopper (plug)]]
** [[Bunghole]]
* [[Keystone (cask)|Keystone]]
* [[Tap (valve)|Spigot]]

== Notes ==
{{cnote|1|Properly served, there should be no significant quantities of this yeast present in the beer as it is drunk. During the conditioning process, [[finings]] help to gather the yeast into clumps ("[[flocculation]]") which sink into the belly of the cask below the tap. Only if the cask is shaken, tilted too far, or served too early will the yeast find its way into the glass.}}
{{cnote|2|Stronger beers will last longer, mostly because the increased [[alcohol (drug)|alcohol]] content serves as a [[preservative]]. Nevertheless, they may be a little flat by the end of their life..}}

== References ==
{{reflist|1}}

==Bibliography==
* {{cite book |title=Cellarmanship - Caring for Real Ale |edition=2 |date=1992 |publisher=CAMRA |isbn=1-85249-063-2 }}

==External links==
{{external media|image1=[https://www.flickr.com/photos/chiotsrun/4375300279 Maple Spile in Tree] <!--CC BY-NC 2.0-->}}
* {{wikt-inline}}
* {{commons-inline|Category:Spiles}}


[[Category:Brewing]]
[[Category:Tree tapping]]