The Products

Kasé

Two expressions. One forest.

Both products begin with the same hand-tapped Estonian birch sap, fermented naturally for a minimum of six months.

Kasé Original — fermented birch sap bottle
Still
330 ml

Kasé Original

The unaltered expression. Still, dry, and mineral — exactly as the forest intended.

100% pure birch sap, tapped by hand in early spring and fermented naturally for a minimum of six months. No sugar. No preservatives. No carbonation. The faint effervescence you taste is a natural byproduct of fermentation — the forest's own signature.

Volume

330 ml

Price

$11.99

One ingredient. One harvest. One expression.

Kasé Carbonated — 250ml aluminum can
Sparkling

Kasé Carbonated

A completely unique spark. The same fermented birch sap — now alive with fine carbonation.

Everything that makes Kasé Original extraordinary, now with an added dimension. Fine carbonation amplifies the mineral character and lifts the dry, tart finish into something entirely its own. There is nothing else like it. A sparkling beverage with genuine provenance — not flavoured, not sweetened, not engineered. Just birch, fermentation, and effervescence.

Volume

250 ml

Price

$8.99

Same forest. New energy.

Kasé Original — fermented birch sap bottle

Kasé Original — In Detail

A single-origin fermented beverage from the birch forests of Estonia. One ingredient. One harvest. One expression.

Kasé Original is made from 100% pure birch sap, tapped by hand in early spring from Estonian birch forests and fermented naturally for a minimum of six months.

No sugar is added. No preservatives. No carbonation. The faint effervescence you taste is a natural byproduct of fermentation — the forest's own signature.

Origin

Estonia

Ingredient

100% Birch Sap

Fermentation

Minimum 6 months

Additives

None

Sugar

0g added

Calories

0 kcal

Volume

330 ml

Price

$11.99 / bottle

Kasé Carbonated — In Detail

A completely unique spark. The same fermented birch sap — now alive with fine carbonation.

Everything that makes Kasé Original extraordinary, now with an added dimension. Fine carbonation amplifies the mineral character and lifts the dry, tart finish into something entirely its own. There is nothing else like it. A sparkling beverage with genuine provenance — not flavoured, not sweetened, not engineered. Just birch, fermentation, and effervescence.

Origin

Estonia

Ingredient

100% Birch Sap

Fermentation

Minimum 6 months

Carbonation

Fine, added

Sugar

0g added

Calories

0 kcal

Volume

250 ml

Price

$8.99 / can

Kasé Carbonated — 250ml aluminum can

Tasting Notes

"Clean on entry. Faintly effervescent. Mineral, with a whisper of tart — like cold spring water with memory. A long, dry finish that lingers without sweetness."

For best taste, consume chilled, 40-55°F. Best enjoyed alone or alongside raw seafood, aged cheese, or light Nordic cuisine.

Nutritional information

What's inside.

Birch sap contains a naturally occurring mineral profile that no other plant beverage can replicate. Fermentation preserves and concentrates these qualities.

Key mineral

Manganese

One bottle of Kasé provides a daily dose of manganese — a trace mineral rarely found in meaningful concentrations in any beverage.

Birch sap is one of the few natural liquid sources of bioavailable manganese.

What it supports

Manganese activates the body's primary antioxidant enzyme, superoxide dismutase (SOD), which neutralises free radicals at the cellular level. It also supports bone formation, carbohydrate metabolism, and connective tissue synthesis.

Trace minerals

Kasé has various other naturally occurring trace minerals which contribute to its clean, complex mineral character.

Potassium

Electrolyte balance & heart function

Magnesium

Muscle relaxation & nerve signalling

Calcium

Bone density & cellular signalling

Zinc

Immune defence & cellular repair

Phosphorus

Energy metabolism & bone structure

Iron

Oxygen transport in the blood

Live lactic cultures

Natural fermentation introduces a community of lactic acid bacteria — primarily Lactobacillus species — that are present in every bottle of Kasé. These cultures are a byproduct of the fermentation process, not an additive. Birch sap also contains naturally occurring betulin, saponins, and small amounts of fructose, which feed the fermentation and contribute to the dry, slightly tart finish.

Lactic acid bacteria

Naturally occurring from fermentation

Betulin

Birch-specific triterpene with antioxidant properties

Saponins

Natural plant compounds found in birch sap

Xylitol (trace)

Naturally present in birch — not added

Organic acids

Malic, citric, and lactic acids from fermentation

Official Label

Kasé Original — Nutritional Panel

Kasé Original official nutritional label

Secure your allocation.

Kasé is available by subscription only. Each year's harvest is finite — once allocations are filled, the next shipment is twelve months away.

Kasé

Fermented birch sap from the ancient forests of Estonia. Pure. Unaltered. Alive.

Origin

Harvested in Estonia.
Shipped to the United States.

Subscription only.
Limited annual harvest.

© 2026 Kasé. All rights reserved.

Shipped from Estonia to the United States