![Collecting of birch sap](https://upload.wikimedia.org/wikipedia/commons/a/a0/Collecting_of_birch_sap.jpg)
Birch sap, birch water or birch juice is the
sap
Sap is a fluid transported in xylem cells (vessel elements or tracheids) or phloem sieve tube elements of a plant. These cells transport water and nutrients throughout the plant.
Sap is distinct from latex, resin, or cell sap; it is a separ ...
directly tapped from
birch
A birch is a thin-leaved deciduous hardwood tree of the genus ''Betula'' (), in the family Betulaceae, which also includes alders, hazels, and hornbeams. It is closely related to the beech- oak family Fagaceae. The genus ''Betula'' contains ...
trees, ''
Betula pubescens
''Betula pubescens'' (syn. ''Betula alba''), commonly known as downy birch and also as moor birch, white birch, European white birch or hairy birch, is a species of deciduous tree, native and abundant throughout northern Europe and northern Asia ...
'' (white birch), ''
Betula pendula
''Betula pendula'', commonly known as silver birch, warty birch, European white birch, or East Asian white birch, is a species of tree in the family Betulaceae, native to Europe and parts of Asia, though in southern Europe, it is only found ...
'' (silver birch), ''
Betula lenta'', ''
Betula papyrifera
''Betula papyrifera'' (paper birch, also known as (American) white birch and canoe birch) is a short-lived species of birch native to northern North America. Paper birch is named for the tree's thin white bark, which often peels in paper like ...
'', and ''
Betula fontinalis''.
Birch sap may be consumed both fresh and
naturally fermented. When fresh, it is a clear and uncoloured liquid, often slightly sweet with a slightly silky texture. After two to three days, the sap starts fermenting and the taste becomes more acidic.
Birch sap is a traditional beverage in
boreal and
hemiboreal
Hemiboreal means halfway between the temperate and subarctic (or boreal) zones. The term is most frequently used in the context of climates and ecosystems.
Botany
A hemiboreal forest has some characteristics of a boreal forest to the north, and ...
regions of the Northern Hemisphere
as well as parts of northern
China.
Harvest
Birch sap is collected only at the break of winter and spring when the sap moves intensively.
Birch sap collection is done by drilling a hole into the tree trunk and leading the sap into a container via some conduit (a tube or simply a thin twig); the sap will flow along it because of the
surface tension. The wound is then plugged to minimise infection.
Birch sap has to be collected in early spring before any green leaves have appeared, as in late spring it becomes bitter. The collection period is only about a month per year.
No published evidence exists to quantify the long-term impacts of sap harvest on birch tree and birch forest health, or birch timber quality.
However, the wounds caused by tapping birches consistently lead to dark staining in the wood.
In one study, infection and wood decay had spread from more than half of old tapping holes.
In comparison to maples, birch trees are considered far less tolerant to the wounds caused by tapping, so more conservative harvesting practises have been recommended by trade bodies such as the Alaska Birch Syrupmakers Association.
Traditional regions
Ancient
Balts
The Balts or Baltic peoples ( lt, baltai, lv, balti) are an ethno-linguistic group of peoples who speak the Baltic languages of the Balto-Slavic branch of the Indo-European languages.
One of the features of Baltic languages is the number ...
,
Slavs and
Finns
Finns or Finnish people ( fi, suomalaiset, ) are a Baltic Finnic ethnic group native to Finland.
Finns are traditionally divided into smaller regional groups that span several countries adjacent to Finland, both those who are native to these ...
regarded birch as one of their most sacred trees and made a traditional beverage from it.
Slavic regions
In Slavic regions the sap is known as ''birch juice'' as in
Russia
Russia (, , ), or the Russian Federation, is a transcontinental country spanning Eastern Europe and Northern Asia. It is the largest country in the world, with its internationally recognised territory covering , and encompassing one-eig ...
(russian: берёзовый сок, translit=byeryozovyi sok),
Belarus
Belarus,, , ; alternatively and formerly known as Byelorussia (from Russian ). officially the Republic of Belarus,; rus, Республика Беларусь, Respublika Belarus. is a landlocked country in Eastern Europe. It is bordered by ...
( be, бярозавы сок, translit=biarozavy sok,
Byarozavik),
Bulgaria
Bulgaria (; bg, България, Bǎlgariya), officially the Republic of Bulgaria,, ) is a country in Southeast Europe. It is situated on the eastern flank of the Balkans, and is bordered by Romania to the north, Serbia and North Macedo ...
(
Bulgarian: брезов сок,
romanized: ''brezov sok''),
Poland
Poland, officially the Republic of Poland, is a country in Central Europe. It is divided into 16 administrative provinces called voivodeships, covering an area of . Poland has a population of over 38 million and is the fifth-most populou ...
( pl, sok z brzozy, oskoła),
Slovakia
Slovakia (; sk, Slovensko ), officially the Slovak Republic ( sk, Slovenská republika, links=no ), is a landlocked country in Central Europe. It is bordered by Poland to the north, Ukraine to the east, Hungary to the south, Austria to the s ...
( sk, brezová šťava),
Ukraine
Ukraine ( uk, Україна, Ukraïna, ) is a country in Eastern Europe. It is the second-largest European country after Russia, which it borders to the east and northeast. Ukraine covers approximately . Prior to the ongoing Russian inv ...
( uk, березовий сік, translit=berezovyi sik).
Baltic regions
Estonia
Estonia, formally the Republic of Estonia, is a country by the Baltic Sea in Northern Europe. It is bordered to the north by the Gulf of Finland across from Finland, to the west by the sea across from Sweden, to the south by Latvia, a ...
( et, kasemahl),
Finland
Finland ( fi, Suomi ; sv, Finland ), officially the Republic of Finland (; ), is a Nordic country in Northern Europe. It shares land borders with Sweden to the northwest, Norway to the north, and Russia to the east, with the Gulf of B ...
( fi, mahla),
Latvia ( lv, bērzu sula),
Lithuania ( lt, beržo sula, beržų sula).
Other regions
France, Scotland, Norway,
Sweden ( sv, björksav) and elsewhere in
Northern Europe as well as parts of northern
China and both
Hokkaido
is Japan's second largest island and comprises the largest and northernmost prefecture, making up its own region. The Tsugaru Strait separates Hokkaidō from Honshu; the two islands are connected by the undersea railway Seikan Tunnel.
The lar ...
and
Aomori as parts of northern
Japan.
It is also widely used among the
Pennsylvania Dutch, both as a traditional beverage in its own right, and particularly as a key ingredient in
birch beer
Birch beer is a beverage, commonly found as a carbonated soft drink made from herbal extracts and birch bark. It was originally made from the extracts of both oak and pine barks (which are sometimes combined). There are dozens of brands of birch ...
.
Composition
Birch sap contains heterosides (
betuloside and monotropitoside),
17
amino acids including glutamic acid,
as well as
minerals
In geology and mineralogy, a mineral or mineral species is, broadly speaking, a solid chemical compound with a fairly well-defined chemical composition and a specific crystal structure that occurs naturally in pure form.John P. Rafferty, ed ...
,
enzyme
Enzymes () are proteins that act as biological catalysts by accelerating chemical reactions. The molecules upon which enzymes may act are called substrates, and the enzyme converts the substrates into different molecules known as products ...
s,
proteins,
betulinic acid and
betulin,
antioxidants
Antioxidants are compounds that inhibit oxidation, a chemical reaction that can produce free radicals. This can lead to polymerization and other chain reactions. They are frequently added to industrial products, such as fuels and lubricants, ...
,
sugar (
fructose,
glucose
Glucose is a simple sugar with the molecular formula . Glucose is overall the most abundant monosaccharide, a subcategory of carbohydrates. Glucose is mainly made by plants and most algae during photosynthesis from water and carbon dioxide, u ...
and small amounts of
sucrose) and
vitamins
A vitamin is an organic molecule (or a set of molecules closely related chemically, i.e. vitamers) that is an essential micronutrient that an organism needs in small quantities for the proper functioning of its metabolism. Essential nutrien ...
(C and B(group)).
Contrary to popular belief, there is no
xylitol
Xylitol is a chemical compound with the formula , or HO(CH2)(CHOH)3(CH2)OH; specifically, one particular stereoisomer with that structural formula. It is a colorless or white crystalline solid that is freely soluble in water. It can be classifi ...
in birch sap (xylitol is a
sugar alcohol
Sugar alcohols (also called polyhydric alcohols, polyalcohols, alditols or glycitols) are organic compounds, typically derived from sugars, containing one hydroxyl group (–OH) attached to each carbon atom. They are white, water-soluble solids ...
that is industrially produced using high temperature and sulfuric acid, or through fermentation).
Nutritional and medicinal uses
Folk uses
Folk uses have been documented which include medicinal use, supplementary nutrition, and cosmetic applications for skin and hair.
Commercial birch sap and derivative products
![Berezovii sok](https://upload.wikimedia.org/wikipedia/commons/6/61/Berezovii_sok.JPG)
Birch sap may be consumed both fresh and
naturally fermented. Fresh birch sap is highly perishable; even if refrigerated, it is stable for only up 7 days. Shelf life can be prolonged by freezing or preservation techniques. Existing preservation techniques include:
[Nicole & Olivier Lhomme, NICOLL-Nature, Le Bio Logis]
La sève de bouleau
/ref>
* Nothing i.e. bottled fresh sap (shelf life: 2–5 days refrigerated)
* Filtered with a 0.22-μ net (shelf life: 3 weeks refrigerated)
* Collected under anaerobic conditions (shelf life: 1 year ambient)
* Added sugar (3 g per 100 ml)
* Heat pasteurized, pasteurization should be conducted under specific temperature levels and times (shelf life: 1 year ambient). Although level of Vitamin C is lower than in fresh sap, all other benefits are preserved.
* Frozen at −25 °C (shelf life: 2 years)
Birch sap can also be used as an ingredient in food or drinks, such as birch beer
Birch beer is a beverage, commonly found as a carbonated soft drink made from herbal extracts and birch bark. It was originally made from the extracts of both oak and pine barks (which are sometimes combined). There are dozens of brands of birch ...
or wintergreen
Wintergreen is a group of aromatic plants. The term "wintergreen" once commonly referred to plants that remain green (continue photosynthesis) throughout the winter. The term "evergreen" is now more commonly used for this characteristic.
Most ...
-flavored candy.
Concentrated birch sap is used to make birch syrup
A birch is a thin-leaved deciduous hardwood tree of the genus ''Betula'' (), in the family Betulaceae, which also includes alders, hazels, and hornbeams. It is closely related to the beech-oak family Fagaceae. The genus ''Betula'' contains 30 to ...
, a very expensive type of syrup
In cooking, a syrup (less commonly sirup; from ar, شراب; , beverage, wine and la, sirupus) is a condiment that is a thick, viscous liquid consisting primarily of a solution of sugar in water, containing a large amount of dissolved sugars ...
mainly made from paper birch
''Betula papyrifera'' (paper birch, also known as (American) white birch and canoe birch) is a short-lived species of birch native to northern North America. Paper birch is named for the tree's thin white bark, which often peels in paper like ...
in Alaska
Alaska ( ; russian: Аляска, Alyaska; ale, Alax̂sxax̂; ; ems, Alas'kaaq; Yup'ik: ''Alaskaq''; tli, Anáaski) is a state located in the Western United States on the northwest extremity of North America. A semi-exclave of the U.S. ...
[Alaska Birch syrupmakers associatio]
Petition to US Food and Drug Administration for establishment of Standard of Identity for birch syrup, including the Alaska Birch Syrupmakers' Association Best Practices
July 18, 2005. and Canada, and from several species in Latvia, Russia
Russia (, , ), or the Russian Federation, is a transcontinental country spanning Eastern Europe and Northern Asia. It is the largest country in the world, with its internationally recognised territory covering , and encompassing one-eig ...
, Belarus
Belarus,, , ; alternatively and formerly known as Byelorussia (from Russian ). officially the Republic of Belarus,; rus, Республика Беларусь, Respublika Belarus. is a landlocked country in Eastern Europe. It is bordered by ...
, and Ukraine
Ukraine ( uk, Україна, Ukraïna, ) is a country in Eastern Europe. It is the second-largest European country after Russia, which it borders to the east and northeast. Ukraine covers approximately . Prior to the ongoing Russian inv ...
.
References
External links
*
{{Forestry
Non-alcoholic drinks
Alcoholic drinks
Tree tapping
Betula