Is Riboflavin (B2 / E101) vegan?

Vegan· E101

Short answer

Riboflavin (B2 / E101) is vegan. Riboflavin used as yellow coloring is bacterial-fermentation derived. Vegan.

Key takeaways

  • Verdict: Riboflavin (B2 / E101) is vegan.
  • Commonly found in: Cereals, Yellow drinks, Cheese-style vegan products.
  • Vegan alternatives: N/A — already vegan.
  • Also listed as: vitamin B2.
  • Scan any barcode with VeggieOS (100% free) for an instant vegan verdict.

Also known as: vitamin B2

What it is

Vitamin B2, produced by fermenting Ashbya gossypii or Bacillus subtilis.

Why vegan

Microbial fermentation, no animal inputs.

What a “Vegan” verdict means

A vegan verdict means the ingredient itself contains no animal-derived material and is not conventionally produced using animal inputs. It does not guarantee the finished product is vegan: the same label can carry dairy, egg or honey elsewhere in the list, and shared production lines can add 'may contain milk' warnings.

Where you'll find it

  • Cereals
  • Yellow drinks
  • Cheese-style vegan products

At a glance

Summary of Riboflavin (B2 / E101) for plant-based shoppers
Verdict✅ Vegan
Ingredient familyColourings
E-number / codeE101
Also listed asvitamin B2
Typical productsCereals, Yellow drinks, Cheese-style vegan products
Best vegan swapN/A — already vegan
Settled by certification?Not required

How to read the label

Riboflavin (B2 / E101) belongs to the colourings family. These are the terms worth scanning for on any ingredient list in this category:

  • E120
  • Carmine
  • Carminic acid
  • Cochineal
  • Natural Red 4
  • CI 75470
  • Crimson Lake
  1. Search any red, pink or purple product for E120 and CI 75470 first.
  2. In cosmetics the same dye appears as CI 75470 — the number differs from the food code.
  3. Beetroot red (E162) and anthocyanins (E163) are plant colours and are safe.
  4. 'Natural colour' on a red product is worth a query; synthetic reds are always declared by number.

Mistakes to avoid

Common colourings traps and what to do about them
Where it catches people outWhat to do
Strawberry yoghurt and drinksCarmine is still standard in some markets even where plant reds are available.
Lipstick and blushCarmine is the default red pigment in mainstream cosmetics; look for CI 75470.
Pink ice cream and sweetsCheck even where the flavour is not fruit-based.

Colourings in context

Colour is the additive category with the clearest animal problem: carmine (E120, cochineal, carminic acid) is made by crushing scale insects, and roughly 70,000 insects are needed per kilogram of dye.

Carmine is popular precisely because it is stable, vivid and legally 'natural', so it appears in red and pink foods, drinks, yoghurts, and a very large share of cosmetics — particularly lipsticks and blushes.

Every other widely used colour is either synthetic or plant/mineral derived. Beetroot red, anthocyanins, paprika extract, spirulina blue, annatto and titanium dioxide are all vegan; the animal risk is concentrated in one number.

Does certification help? Both Leaping Bunny and vegan trademarks exclude carmine, so certified cosmetics remove the need to decode CI numbers.

Vegan alternatives

  • N/A — already vegan

FAQ

Is riboflavin in supplements vegan?
Yes — modern industrial riboflavin is fermentation-derived.
Is carmine the only insect-derived colour?
It is the only widely used one. Shellac (E904) is an insect resin used as a glaze rather than a colour.
What is used instead of carmine?
Beetroot concentrate, anthocyanins from black carrot, lycopene from tomato, and synthetic reds such as E129.

Sources

Last reviewed June 4, 2026

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