Fermented birch sap is not known in many places. However, in Eastern Europe, as spring arrives, the beauty of nature is broken by bottles and buckets of different sizes hanging from branches and tree trunks, mainly in birch and maple trees.
The bottles are slowly filled with the clear, slightly sweet, watery birch or maple sap. The juice is wonderful to drink fresh, though some like it better fermented. Fermented birch juice is tangy and very refreshing when served cold. The juice will taste slightly sweeter after a cold winter.
During a few weeks in spring throngs of fans flock to forests to get their annual share of birch juice. But you can also buy it in the market and in shops. We usually get plenty of fresh juice and drink it daily for few weeks. But we also prepare fermented birch sap of different kinds.
Fermented birch sap surprisingly tasty
If you have never tasted fermented birch juice, you might get a pleasant surprise when tasting it. While fresh birch sap is slightly sweet, fermented sap is crisply dry, tangy and a little sparkling.
Some years ago a farmer producing birch juice in Latvia appeared at the World Organic Food fair in Germany. He received so many orders that he had to turn away most of them as he was short on birch juice. People were amazed at how fresh and pure the taste is, especially if they have only previously encountered the pasteurized, sweetened versions of birch juice that are sold in some countries.
When my wife and I first tried birch sap, we immediately fell in love with it. It feels very refreshing to drink. Fresh sap should be consumed fairly quickly. but when fermented, birch sap can be stored much longer.
Properties of birch sap
Interestingly, fresh birch juice has a similar chemical profile as coconut water. The tree sap contains a number of micronutrients.
- Saponins (phytochemicals said to reduce cholesterol, are anti-inflammatory, immunity booster)
- Sugars (xylitol)
- Essential oils
- Amino acids
Birch sap has traditionally been used for its purifying and diuretic properties. The sap is said to promote the elimination of waste from the body as food additives, coloring, uric acid, phosphate and many other substances. Therefore, birch sap has been used for kidney stones, arthritis, inflammatory conditions and to promote clear supple skin.
Birch sap is structured water
Birch sap contains structure water which might explain the benefits. Studies show that structured water help cleanse out toxins and waste, regulate weight, strengthened immunity, supply cells with organic acids, stimulate metabolism, rinse salt precipitation from bone joints and perform many other healing functions.
Research into birch sap’s anti-aging properties at the University of Latvia has prompted some companies to launch a line of birch sap products. Studies on birch juice show that it may stimulate the growth of dermal and epidermal cells and help delay cell ageing. However, for a stronger effect on the skin, a more concentrated birch sap is used in studies.
It seems that birch sap might rejuvenate and protect skin cells from oxidative stress, including ultraviolet rays, environmental pollution and consequences caused by inflammation.
As with most fermented food, also fermented birch sap may have increased benefits compared to fresh sap. Fermenting tree sap was originally a simple way to preserve the juice for a longer time. During fermentation, several new compounds are created in the juice boosting its potency. Fermentation also makes it easier for the body to assimilate the many micro-nutrients present in the juice.
How to ferment birch sap
Fresh birch sap contains natural, beneficial microorganisms that will start to grow within 2-5 days at room temperature. The clear, fresh sap turns cloudy after 2-5 days at room temperature. The sap will slowly turn slightly tangy within a week. The fermented juice can be enjoyed right away or used as a base to produce a fizzier drink.
Fermented birch sap recipe
This is one way to produce a fizzier fermented birch sap. Adding sugar promotes more bubbles as more bacteria produce gas.
- Pour fresh (or slightly fermented) birch sap into a clean bottle that can be tightly closed
- 1 teaspoon sugar per quart of juice
- A few raisins (support fermentation)
- 1 clove (prevents mold)
- 1 small black currant branch
- Leave the birch sap to ferment at room temperature; in 5-7 days it should turn slightly tangy.
- Store in a cool place for another 15-20 days.
Optional: Try a different taste in each bottle, for example peppermint (a clear winner), lemon, juniper berries, ginger.
Sparkling birch sap
If you want more bubbles like a sparkling wine, then add more sugar.
- 1 quart fresh (or already slightly fermented) birch sap
- 2-3 teaspoons sugar
- 4-5 raisins
- Citric acid (or a small piece organic lemon)
Preparation: Add sugar, raisins, and a little citric acid to each bottle. Fill the empty wine or champagne bottles with fresh birch sap until the neck, i.e. not completely full. Put the cork on and tighten the cork with a string to hold it in place when the pressure in the bottle increases. After 15-20 days or longer, it should be ready to drink.
Drinking fermented birch sap
Most experts say fresh birch sap can be treated as water, so it’s hard to overdose. The sugar contents of fresh birch sap are not very high, so it’s safe to drink for most people.
Fresh and fermented birch sap are both great. But a bottle of well-fermented birch sap is hard to resist during warm summer days.
Reference: University of Latvia study