Birch sap is the sap extracted from a birch

Birch

Birch is a tree or shrub of the genus Betula , in the family Betulaceae, closely related to the beech/oak family, Fagaceae. The Betula genus contains 30–60 known taxa...

 tree, such as a North American Sweet Birch

Sweet Birch

Betula lenta is a species of birch native to eastern North America, from southern Maine west to southernmost Ontario, and south in the Appalachian Mountains to northern Georgia.-Characteristics and habitat:It is a medium-sized deciduous tree reaching 20 m tall with...

 or a Silver Birch

Silver Birch

Betula pendula is a widespread European birch, though in southern Europe it is only found at higher altitudes. Its range extends into southwest Asia in the mountains of northern Turkey and the Caucasus...

. The sap is often a slightly sweet, thin syrupy-watery liquid. The tree sap contains sugar

Sugar

Sugar is a class of edible crystalline carbohydrates, mainly sucrose, lactose, and fructose, characterized by a sweet flavor.Sucrose in its refined form primarily comes from sugar cane and sugar beet...

s (namely xylitol

Xylitol

Xylitol is a sugar alcohol sweetener used as a naturally occurring sugar substitute. It is found in the fibers of many fruits and vegetables, and can be extracted from various berries, oats, and mushrooms, as well as fibrous material such as corn husks and sugar cane bagasse, and birch...

), protein

Protein

Proteins are biochemical compounds consisting of one or more polypeptides typically folded into a globular or fibrous form, facilitating a biological function. A polypeptide is a single linear polymer chain of amino acids bonded together by peptide bonds between the carboxyl and amino groups of...

s, amino acid

Amino acid

Amino acids are molecules containing an amine group, a carboxylic acid group and a side-chain that varies between different amino acids. The key elements of an amino acid are carbon, hydrogen, oxygen, and nitrogen...

s, and enzyme

Enzyme

Enzymes are proteins that catalyze chemical reactions. In enzymatic reactions, the molecules at the beginning of the process, called substrates, are converted into different molecules, called products. Almost all chemical reactions in a biological cell need enzymes in order to occur at rates...

s.

Birch sap must be collected during a specific time of the year, depending on the species and geography, at the break of winter and spring when the sap moves intensively, typically between the first thaws and the start of bud

Bud

In botany, a bud is an undeveloped or embryonic shoot and normally occurs in the axil of a leaf or at the tip of the stem. Once formed, a bud may remain for some time in a dormant condition, or it may form a shoot immediately. Buds may be specialized to develop flowers or short shoots, or may have...

 development. The collected sap can be drunk as a tonic and it is a traditional beverage in Russia

Russia

Russia or , officially known as both Russia and the Russian Federation , is a country in northern Eurasia. It is a federal semi-presidential republic, comprising 83 federal subjects...

 , Latvia

Latvia

Latvia , officially the Republic of Latvia , is a country in the Baltic region of Northern Europe. It is bordered to the north by Estonia , to the south by Lithuania , to the east by the Russian Federation , to the southeast by Belarus and shares maritime borders to the west with Sweden...

 , Estonia

Estonia

Estonia , officially the Republic of Estonia , is a state in the Baltic region of Northern Europe. It is bordered to the north by the Gulf of Finland, to the west by the Baltic Sea, to the south by Latvia , and to the east by Lake Peipsi and the Russian Federation . Across the Baltic Sea lies...

 , Finland

Finland

Finland , officially the Republic of Finland, is a Nordic country situated in the Fennoscandian region of Northern Europe. It is bordered by Sweden in the west, Norway in the north and Russia in the east, while Estonia lies to its south across the Gulf of Finland.Around 5.4 million people reside...

, Lithuania

Lithuania

Lithuania , officially the Republic of Lithuania is a country in Northern Europe, the biggest of the three Baltic states. It is situated along the southeastern shore of the Baltic Sea, whereby to the west lie Sweden and Denmark...

 , Belarus

Belarus

Belarus , officially the Republic of Belarus, is a landlocked country in Eastern Europe, bordered clockwise by Russia to the northeast, Ukraine to the south, Poland to the west, and Lithuania and Latvia to the northwest. Its capital is Minsk; other major cities include Brest, Grodno , Gomel ,...

 ' onMouseout='HidePop("10418")' href="/topics/Byarozavik">Byarozavik

Byarozavik

Byarozavik is a Belarusian traditional drink made from birch sap which is harvested from birch trees once a year from March to April. Due the damaged caused to trees by the popularity of this drink, a licensing system for the collection of sap was introduced in 2008....

), Poland

Poland

Poland , officially the Republic of Poland , is a country in Central Europe bordered by Germany to the west; the Czech Republic and Slovakia to the south; Ukraine, Belarus and Lithuania to the east; and the Baltic Sea and Kaliningrad Oblast, a Russian exclave, to the north...

 , Ukraine

Ukraine

Ukraine is a country in Eastern Europe. It has an area of 603,628 km², making it the second largest contiguous country on the European continent, after Russia...

  and elsewhere in Northern Europe

Northern Europe

Northern Europe is the northern part or region of Europe. Northern Europe typically refers to the seven countries in the northern part of the European subcontinent which includes Denmark, Estonia, Latvia, Lithuania, Norway, Finland and Sweden...

 as well as parts of northern China

China

Chinese civilization may refer to:* China for more general discussion of the country.* Chinese culture* Greater China, the transnational community of ethnic Chinese.* History of China* Sinosphere, the area historically affected by Chinese culture...

.

Birch sap collection is done by tying a bottle to the tree, drilling a hole into its trunk and leading the sap to the bottle by a plastic tube. A small birch (trunk diameter about 15 cm) can produce up to 5 liters of sap per day, a larger tree (diameter 30 cm) up to 15 liters per day. 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. The price of birch sap is correspondingly high in some countries, e.g. in Japan reaching up to 50 Euro

Euro

The euro is the official currency of the eurozone: 17 of the 27 member states of the European Union. It is also the currency used by the Institutions of the European Union. The eurozone consists of Austria, Belgium, Cyprus, Estonia, Finland, France, Germany, Greece, Ireland, Italy, Luxembourg,...

 per liter.

Birch sap may be consumed both fresh and naturally fermented.

Birch sap can also be used as an ingredient in food or drinks, such as birch beer

Birch beer

Birch beer is a carbonated soft drink made from herbal extracts, usually from birch bark. It has a taste similar to root beer. Various types of birch beer are available, distinguished by color. The color depends on the species of birch tree from which the sap is extracted...

 or wintergreen

Wintergreen

Wintergreen is a group of plants. Wintergreen once commonly referred to plants that continue photosynthesis throughout the winter...

 flavored candy

Candy

Candy, specifically sugar candy, is a confection made from a concentrated solution of sugar in water, to which flavorings and colorants are added...

.

Concentrated birch sap is used to make birch syrup

Birch syrup

Birch syrup is a sweetener made from the sap of birch trees, and used in much the same way as maple syrup. It is used for pancake or waffle syrup, to make candies, as an ingredient in sauces, glazes, and dressings, and as a flavoring in ice cream, beer, wine, and soft drinks...

, a very expensive type of syrup

Syrup

In cooking, a syrup is a thick, viscous liquid consisting primarily of a solution of sugar in water, containing a large amount of dissolved sugars but showing little tendency to deposit crystals...

 mainly made from paper birch

Paper Birch

Betula papyrifera is a species of birch native to northern North America.-Description:...

 in Alaska

Alaska

Alaska is the largest state in the United States by area. It is situated in the northwest extremity of the North American continent, with Canada to the east, the Arctic Ocean to the north, and the Pacific Ocean to the west and south, with Russia further west across the Bering Strait...

, and from several species in Russia

Russia

Russia or , officially known as both Russia and the Russian Federation , is a country in northern Eurasia. It is a federal semi-presidential republic, comprising 83 federal subjects...

, Belarus

Belarus

Belarus , officially the Republic of Belarus, is a landlocked country in Eastern Europe, bordered clockwise by Russia to the northeast, Ukraine to the south, Poland to the west, and Lithuania and Latvia to the northwest. Its capital is Minsk; other major cities include Brest, Grodno , Gomel ,...

 and Ukraine

Ukraine

Ukraine is a country in Eastern Europe. It has an area of 603,628 km², making it the second largest contiguous country on the European continent, after Russia...

. In Russia this tonic is used as a traditional herbal medicine functioning as antiseptic

Antiseptic

Antiseptics are antimicrobial substances that are applied to living tissue/skin to reduce the possibility of infection, sepsis, or putrefaction...

, anti-parasitic

Anti-parasitic

Antiparasitics are a class of medications which are indicated for the treatment of parasitic diseases such as nematodes, cestodes, trematodes, infectious protozoa, and amoebas.-Antinematodes:* Mebendazole...

, anti-inflammatory

Anti-inflammatory

Anti-inflammatory refers to the property of a substance or treatment that reduces inflammation. Anti-inflammatory drugs make up about half of analgesics, remedying pain by reducing inflammation as opposed to opioids, which affect the central nervous system....

, and anti-itching treatment.

Fresh birch sap is highly perishable; even if refrigerated, it is stable for only up to 2-5 days. Shelf life can be prolonged by freezing or pasteurization

Pasteurization

Pasteurization is a process of heating a food, usually liquid, to a specific temperature for a definite length of time, and then cooling it immediately. This process slows microbial growth in food...

. However pasteurization destroys some ingredients and can alter the taste of the product. Frozen birch sap is fairly stable. In Russia and Belarus commercial birch sap is usually preserved with food-grade acids, mainly phosphoric

Phosphoric acid

Phosphoric acid, also known as orthophosphoric acid or phosphoric acid, is a mineral acid having the chemical formula H3PO4. Orthophosphoric acid molecules can combine with themselves to form a variety of compounds which are also referred to as phosphoric acids, but in a more general way...

 or citric

Citric acid

Citric acid is a weak organic acid. It is a natural preservative/conservative and is also used to add an acidic, or sour, taste to foods and soft drinks...

one, as if some sugar is added to mask acidity, it affects the flavor less than pasteurization.