How much sugar and how many calories are in Rudy's Kombucha?
Between 8 and 18 kcal per 100 ml, and between 0.8 and 2.4 g of sugars per 100 ml, depending on the flavour. Lemon & Ginger, Rhubarb, Pear & Fireweed by Madara Meiere and Matcha & Passion Fruit are the lightest at 8 kcal per 100 ml; Pineapple & Peach is the highest at 18.
Every certified flavour falls between 8 and 18 kcal per 100 ml.
Sugars run from 0.8 to 2.4 g per 100 ml, all of it from the fruit and the tea.
No sugar is added; the balance is finished with erythritol, xylitol or steviol glycosides.
Per 100 ml, by flavour
Read from the ingredients and quality certificate for each flavour. Energy first, then sugars.
Lemon & Ginger: 8 kcal per 100 ml, 0.8 g sugars per 100 ml
Matcha & Passion Fruit: 8 kcal per 100 ml, 0.8 g sugars per 100 ml
Pear & Fireweed: 8 kcal per 100 ml, 1.0 g sugars per 100 ml
Rhubarb: 8 kcal per 100 ml, 1.1 g sugars per 100 ml
Raspberry & Basil: 10 kcal per 100 ml, 1.0 g sugars per 100 ml
Mango & Passion Fruit: 11 kcal per 100 ml, 1.2 g sugars per 100 ml
Mandarin & Yuzu: 11 kcal per 100 ml, 2.2 g sugars per 100 ml
Coconut & Pineapple: 12 kcal per 100 ml, 2.1 g sugars per 100 ml
Pineapple & Peach: 18 kcal per 100 ml, 2.4 g sugars per 100 ml
For a whole can
A can holds 330 ml, so multiply any figure in the list above by 3.3.
The rest of the declaration
The same certificates give fat as 0 g per 100 ml, protein as under 0.01 g per 100 ml, salt as under 0.1 g per 100 ml, and fibre as 1.6 g per 100 ml across the range.
Where the sugars come from
The tea and the fruit bring their own sugars, and fermentation eats most of them. Nothing sweet goes in on top: the finish comes from erythritol, and in some flavours xylitol or steviol glycosides, which the label lists as sweeteners. Cold Brew Coffee & Orange and Dragon Fruit Mojito are not listed because we do not yet publish a certified nutrition table for them.
Energy and sugars per 100 ml, from the ingredients and quality certificates
Erythritol in eight of the nine certified flavours, often with xylitol or steviol glycosides alongside it. Lemon & Ginger uses erythritol on its own; Matcha & Passion Fruit uses steviol glycosides on its own. No sugar is added to any flavour, so the sugars listed come from the fruit and the tea.
Erythritol is the workhorse, at about 1.5 per cent where the certificate states a figure.
Xylitol appears in four flavours, steviol glycosides in four, at 0.005 per cent where stated.
No sugar is added anywhere in the range.
Which flavour uses what
Lemon & Ginger: erythritol
Mango & Passion Fruit: erythritol, xylitol
Pineapple & Peach: erythritol, xylitol
Raspberry & Basil: erythritol, xylitol
Pear & Fireweed by Madara Meiere: erythritol, xylitol
Erythritol and xylitol are polyols, often called sugar alcohols; they occur in fruit and are produced by fermentation for food use. Steviol glycosides are the sweet compounds from the stevia leaf. All three are approved sweeteners in the EU and appear in the ingredient list as sweeteners, which is where you can check them for yourself.
Why sweeten at all
Fermentation eats the sugar. Left alone, the finished kombucha is sharply sour. A small amount of sweetener puts the fruit back in balance without adding sugar, which is how the range stays between 8 and 18 kcal per 100 ml.
What exactly is in a can of Rudy's Kombucha?
Water, kombucha culture, fruit and a sweetener. The kombucha itself is water, green tea and the living culture; on top of that go fruit juice and fruit puree, plant fibres, and erythritol with xylitol or steviol glycosides depending on the flavour. No colours, no stabilisers, no added sugar.
The first two ingredients are always water and the kombucha culture.
Then fruit, at a percentage the certificate prints, then plant fibre, then sweetener.
No colours, no stabilisers and no added sugar anywhere in the range.
The kombucha culture
The certificates spell it out as water, green tea and a SCOBY. In Matcha & Passion Fruit the tea is an infusion of Japanese matcha green tea powder instead of leaf green tea.
The fruit, by flavour
Pineapple & Peach: pineapple juice 20 per cent, peach puree 2 per cent
Raspberry & Basil: raspberry juice 12 per cent, fresh green basil leaves 1 per cent
Rhubarb: rhubarb juice 12 per cent
Mandarin & Yuzu: mandarin juice 10 per cent, yuzu juice 2 per cent
Coconut & Pineapple: pineapple juice 10 per cent, coconut flakes 1 per cent
Matcha & Passion Fruit: passion fruit juice 7 per cent, fresh mint leaves
Mango & Passion Fruit: mango puree 6 per cent, passion fruit juice 5 per cent
Lemon & Ginger: ginger 4 per cent, lemon juice 1 per cent
Pear & Fireweed by Madara Meiere: pear puree 2.5 per cent, fireweed tea 0.5 per cent
The fibre
Every flavour carries 1.6 g of fibre per 100 ml. The certificates name the sources as soluble maize or corn fibre, chicory fibre and, in Coconut & Pineapple, polydextrose.
The sweetener
Erythritol at about 1.5 per cent where the figure is stated, with xylitol or steviol glycosides depending on the flavour. Lemon & Ginger uses erythritol alone; Matcha & Passion Fruit uses steviol glycosides alone.
Does Rudy's Kombucha contain vitamins?
Yes. Every certificate lists, per 100 ml, 19 to 20 mg of vitamin C, 0.34 mg of B1, 0.31 mg of B6, 33 micrograms of B9 and 0.80 micrograms of B12, plus 1.6 g of fibre. Those are the declared amounts on the certificate, and we make no claims beyond them.
The declaration is per 100 ml, and it is the same across the certified range.
Vitamin C 19 to 20 mg, B1 0.34 mg, B6 0.31 mg, B9 33 micrograms, B12 0.80 micrograms.
Fibre 1.6 g per 100 ml, from maize and chicory.
The declared amounts
Per 100 ml, with the reference intake percentage the certificate prints alongside each figure: vitamin C 19 to 20 mg (24 to 25 per cent of the reference intake, depending on flavour); vitamin B1 0.34 mg, at 31 per cent; vitamin B6 0.31 mg, at 22 per cent; vitamin B9 33 micrograms, at 17 per cent; vitamin B12 0.80 micrograms, at 32 per cent.
What we are not saying
Those numbers are a nutrition declaration under EU food-information rules, and that is all they are. We do not tell you what they will do for you, because that is a regulated claim and we have not made one.
Fibre
The same certificates give 1.6 g of fibre per 100 ml. The sources named are soluble maize or corn fibre and chicory fibre, with polydextrose in Coconut & Pineapple.
Ingredients and quality list certificates, Rudys Brewing Co (06.03.2025, 06.07.2025) and Matcha & Passion Fruit product information sheet (12.02.2026) - nutrition facts per 100 ml incl. NRV percentages
Regulation (EU) No 1169/2011 on the provision of food information to consumers: https://eur-lex.europa.eu/eli/reg/2011/1169/oj
