What is kombucha?

Kombucha is a fermented drink made from sweetened tea, lightly effervescent and with an alcohol content of less than 1.2%. It is obtained thanks to a symbiotic colony of bacteria and yeasts called SCOBY, which for weeks transforms sugar into organic acids, vitamins, and natural probiotics. At Mūn Kombucha, we ferment it for a month in small batches since 2015.

What is kombucha

Kombucha is a fermented tea. Just as fermented grape juice becomes wine, or apple juice becomes cider, a fermented sweetened tea infusion becomes kombucha. It is pronounced /kɒmˈbuːtʃə/.

Its preparation is simple but requires time. A symbiotic colony of bacteria and yeasts known as SCOBY (Symbiotic Culture Of Bacteria and Yeast) is added to a sweetened tea infusion. During fermentation, the microorganisms transform the sugar into organic acids, B vitamins, and natural probiotics. The result: a drink with soft bubbles, a taste between sweet and sour, and properties associated with digestive balance.

What kombucha contains

As a result of the fermentation of sugar by yeasts and bacteria, kombucha contains:

• B vitamins (B1, B2, B3, B6, B9, B12), C, D, E and K.
• Organic acids such as lactic, acetic, and glucuronic, which provide the characteristic flavour and act as antioxidants.
• Enzymes that contribute to the digestive process.
• Minerals: iron, potassium, zinc, manganese, copper, calcium, and magnesium.
• Natural probiotics, beneficial bacteria associated with gut health and the immune system.
• Polyphenols from tea, with an antioxidant effect.

Origins of kombucha

Kombucha consumption has been recorded in Asia for over 2,000 years. The first documented mentions place it in ancient China, from where it spread to Japan, Korea, Russia, and subsequently to Europe and the American continent.

For centuries it was made domestically: the SCOBY was passed down from generation to generation, and each family prepared their own drink. The industrialisation of the product is relatively recent: in Spain, Mūn Ferments was the first company to commercialise authentic kombucha bottled in glass, with 100% natural and organic certified ingredients, since 2015.

How kombucha is made

The process starts with a tea infusion (usually green or black) sweetened with sugar. To this base, the SCOBY is added, a gelatinous mass formed by yeasts and bacteria that work in coordination to ferment the mixture.

The Mūn method

At Mūn Kombucha, we start with organic Lung Ching green tea, a variety harvested in spring. We sweeten it with organic cane sugar, which will serve as fuel for fermentation. We apply a long fermentation of one month that allows microorganisms to consume almost all the sugar and produce organic acids in quantity.

Time as a key variable

Kombucha fermentation follows two phases:

1. First fermentation: yeasts break down sucrose into glucose and fructose, producing ethanol and carbon dioxide. Bacteria then convert these simple sugars and ethanol into organic acids.
2. Second fermentation: this is carried out in the bottle, adding fruit juices or infusions that provide flavour and natural carbonation.

If the process is interrupted prematurely, a lot of residual sugar and little organic acid remain. This is why cheap or industrial kombucha almost always contains more sugar than it should.

Benefits of kombucha

The benefits attributed to kombucha are associated with three main components: probiotics, organic acids, and tea polyphenols. Scientific evidence supports the following effects:

Digestive support

The natural probiotics present in kombucha help maintain the balance of the gut microbiota. This can aid more efficient digestion and nutrient absorption.

Immune system support

Approximately 70% of the immune system resides in the gut. A balanced microbiota is associated with a better immune response.

Antioxidant contribution

Tea polyphenols and organic acids produced during fermentation have antioxidant capacity, protecting cells from oxidative stress.

Hydration with low sugar

Authentic kombucha with long fermentation provides flavour and bubbles with very little added sugar. It is an alternative to sugary soft drinks.

Important: kombucha is not a medicine and does not replace a balanced diet. Its benefits are associated with regular consumption as part of a varied diet.

Does kombucha contain alcohol?

Yes, it contains a small amount of residual alcohol resulting from fermentation. Below 1.2% by volume, it is legally considered a non-alcoholic drink. At Mūn Kombucha, the percentage remains below 1%. More information in our guide on alcohol in kombucha.

Does kombucha contain caffeine?

It contains a small amount of theine from the base tea. A 250 ml bottle of Mūn Kombucha provides approximately 10-15 mg of theine, well below the 80-100 mg of an espresso coffee. Long fermentation reduces part of the initial content. More details in does kombucha contain caffeine?

Kombucha contraindications

Although it is a safe drink for most healthy adults, it has contraindications that should be known:

• Pregnancy and breastfeeding: not recommended due to residual alcohol content and the presence of unpasteurised live bacteria.
• Children under 3 years old: avoid.
• Liver or kidney diseases: consult a doctor before incorporating it.
• Immunocompromised individuals: caution due to the presence of live microorganisms.
• Anticoagulant treatments: consult a doctor.

Consult our complete guide to contraindications.

How and when to drink kombucha

It is drunk cold, directly from the bottle or can. It is most commonly consumed on an empty stomach or between meals to take advantage of the effect of probiotics on the microbiota.

If you have never tried it, start with small amounts (100-150 ml per day) during the first week and gradually increase. The recommended amount for a healthy adult is 250 to 500 ml per day. Complete guide in how and when to drink kombucha.

Can kombucha be made at home?

Yes, but it requires patience and control. You need:

• A quality SCOBY and starter liquid (unpasteurised kombucha).
• Tea (green or black) and organic ingredients.
• Sugar.
• A glass container.
• Temperature (20-25°C), pH, and fermentation time control.

Follow our guide to making kombucha at home step by step. If you prefer consistency and health guarantees, professionally made kombuchas like Mūn's undergo controls that homemade preparation does not ensure.

Where to buy authentic kombucha

Mūn Kombucha is available at over 8,000 points of sale in Spain:

• Supermarkets: Mercadona, Lidl, Carrefour, Alcampo, El Corte Inglés, Consum.
• Organic shops: Veritas, Ametller Origen, Bonpreu Esclat.
• Online: in our shop with 24-48h delivery on the peninsula.

If you live in Barcelona or Madrid, also check where to buy in Barcelona or where to buy in Madrid.

How to recognise authentic kombucha

There is no specific European regulation governing the term "kombucha". Any brand can label its product as such, even if it has undergone processes that distance it from traditional kombucha. The Kombucha Brewers International (KBI), of which Mūn Ferments has been a member since 2017, has published a code of good practices that distinguishes three categories:

• Traditional kombucha: natural fermentation of sweetened tea with SCOBY, without subsequent processing. It can generate a new SCOBY at room temperature.
• Kombucha: fermentation of a wider range of plants with SCOBY. May or may not generate SCOBY depending on the process.
• Kombucha soft drink: kombucha subjected to processes such as pasteurisation, dealcoholisation, filtration, or dilution.

How to distinguish good kombucha when buying

Three key aspects to check on the label:

1. List of ingredients. Good kombucha contains: water, tea, sugar, kombucha culture and, optionally, fruits, roots, or infusions for flavouring. If you see sparkling water, sweeteners (steviol glycosides, erythritol), flavourings, or concentrates, it is probably a kombucha-flavoured soft drink, not authentic kombucha.

2. Residual sugar. Kombucha with long fermentation has low residual sugar. A maximum of 1-2 g per 100 ml is a sign of careful preparation. Much more than that indicates short fermentation or subsequent added sugar. You can compare the sugar content of Mūn kombuchas with other drinks in our calculator.

3. Does it need refrigeration? Authentic kombucha with low sugar is stable at room temperature. Those that strictly require refrigeration are usually those with high residual sugar: cold slows down fermentation and prevents the container from accumulating pressure. Mūn Kombucha does not need refrigeration for preservation, thanks to long fermentation and low sugar content.

Packaging matters

• Glass: the best material. Inert, does not transfer particles, and is recyclable.
• Can: acceptable if guaranteed to be BPA-free. Kombucha is acidic and can react with internal plastic coatings. Mūn Kombucha in cans is BPA-free.
• Plastic: avoid. The acidity of kombucha (pH ~3) favours the migration of particles from the container to the drink.
• Keg: stainless steel ones are the best option. Some plastic kegs have an internal BPA-free aluminium bag (Mūn's case).

More details in our complete guide to recognising good kombucha.

Frequently asked questions about kombucha