Birch sap
| Nutritional value per 100 g (3.5 oz) | |
|---|---|
| Energy | 4.6 kcal (19 kJ) |
|
1.1 g
|
|
| Sugars | 1.1 g |
| Dietary fiber | 0 g |
|
less than 0.1 g
|
|
| Minerals | |
| Calcium |
(6%)
60 mg |
| Iron |
(1%)
0.1 mg |
| Magnesium |
(3%)
11 mg |
| Manganese |
(52%)
1.1 mg |
| Phosphorus |
(1%)
6.4 mg |
| Potassium |
(3%)
120 mg |
|
|
| Percentages are roughly approximated using US recommendations for adults. | |
Birch sap or birch water is the sap directly tapped from birch trees, Betula alba (white birch), Betula pendula (silver birch), Betula lenta, Betula papyrifera, 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 regions of the northern hemisphere as well as parts of northern China.
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 its 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.
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. Tapping a tree does not harm the health of the tree. If the tap hole is not well plugged with a round tight fitting dowel there is a possibility that the sap continues to flow causing not only a loss of nutriment but also a risk of infection and fungal attack. This is best mitigated by the addition of pine tar (generally available at garden suppliers).
Birch sap was a traditional beverage in Russia (Russian: берёзовый сок / byeryozovyi sok), Latvia (Latvian: bērzu sula), Estonia (Estonian: kasemahl), Finland (Finnish: mahla), Lithuania (Lithuanian: Beržų Sula), Belarus (Belarusian: Бярозавы сок / biarozavy sok, Byarozavik), Poland (Polish: sok z brzozy, oskoła), Ukraine (Ukrainian: Березовий сік / berezovyi sik), France, Scotland and elsewhere in Northern Europe as well as parts of Northern China.
...
Wikipedia