Spices are costly, often ground and traded through long supply chains, which makes them tempting to bulk out or recolour. Here are the best-documented cases and how to reduce the risk.
Why spices get adulterated¶
Spice adulteration is the deliberate addition of something cheaper to a spice, or the passing off of one spice as a better one, for profit. Spices invite it for three reasons. They are valuable by weight, so a small proportion of filler earns real money. Most are sold ground, and a powder hides almost anything. And they pass through many hands between the farm and the shop, with each step a chance for someone to cut the product.
None of this is new. Medieval European towns had officials, the garblers, whose job was to inspect and clean spices, and pepper fraud was punished in several cities. What has changed is the analytical toolkit: laboratories can now identify foreign starches, DNA from other plants and synthetic dyes at very low levels, so modern cases are both easier to find and better documented.
The kinds of fraud¶
| Type | What happens | Typical targets |
|---|---|---|
| Bulking | Cheap filler added to increase weight | Ground pepper, cumin, oregano, chilli |
| Substitution | A cheaper relative sold as the real thing | cassia as cinnamon, safflower as saffron |
| Colouring | Dyes or pigments added to make a spice look fresher or brighter | Chilli, paprika, turmeric, saffron |
| Misdescription | Wrong origin, grade or species claimed | Saffron, vanilla, cardamom |
Fillers found in real cases include starches, ground husks and shells, papaya seeds in black peppercorns, and leaves of other plants in dried oregano. Olive and myrtle leaves have repeatedly turned up in oregano surveys in Europe. Saffron has been faked with safflower and marigold petals, dyed corn silk and even dyed threads of other material; see saffron for how to tell.
Sudan dyes and the 2005 recall¶
The best-known modern case in Britain involved Sudan I, a red synthetic dye used for colouring solvents, oils and waxes. It is not permitted in food anywhere in the EU or UK because it is considered a genotoxic carcinogen, meaning no safe level of intake can be set. In 2003 the European Commission required chilli products imported into the EU to be certified free of Sudan dyes after they had been found in chilli from India.
In February 2005 the UK's Food Standards Agency announced that a batch of chilli powder contaminated with Sudan I had been used by Premier Foods in a Worcester sauce, which had in turn been used as an ingredient by many other manufacturers. The result was one of the largest food recalls in British history, covering several hundred products, from ready meals to soups and sauces. The FSA stressed at the time that the risk to anyone who had eaten the products was very small; the point was that an illegal dye had no business being in the food supply at all. Related dyes such as Sudan III and IV, and Para Red, have been found in chilli, paprika and palm oil in later surveys.
📌 Why the fuss over tiny amounts
Regulators treat genotoxic carcinogens differently from most contaminants. Instead of setting a safe limit, they aim to keep them out entirely. That is why a trace of Sudan I triggers a recall while a slightly high level of, say, dust would not.
Lead chromate in turmeric¶
A more dangerous example comes from Bangladesh, where researchers from Stanford University and the icddr,b research centre in Dhaka traced raised lead levels in the population partly to turmeric. Some processors had been adding lead chromate, an industrial yellow pigment, to polished turmeric roots to give them a brighter colour. Lead is harmful at any level, particularly to children. After the findings were published in 2019, the Bangladesh Food Safety Authority ran an enforcement and public awareness campaign, and follow-up work reported that adulteration in the markets studied fell sharply. The wider story is covered on lead-in-spices.
Reducing the risk at home¶
- Buy whole where you can. It is far harder to adulterate a cinnamon quill, a nutmeg or a cumin seed than their powders. Grinding at home (grinding-spices) also gives better flavour.
- Buy from sellers with a reputation to lose. Large retailers and established specialist merchants test their supply; a market stall selling suspiciously cheap saffron probably does not.
- Be sceptical of price. Real saffron cannot be cheap. If a price looks too good to be true, it usually is.
- Look and smell. A spice that is unusually bright, stains your fingers in an odd way, or smells of little is worth questioning. Turmeric that leaves a greasy, vivid stain or chilli powder that colours water instantly and intensely are not proof of adulteration, but are reasons for caution.
- Report concerns. In the UK, suspected food fraud can be reported to the Food Standards Agency's National Food Crime Unit or to your local authority trading standards or environmental health team.
Home "tests" circulating online, such as floating spices in water, are of limited value. They can catch crude fillers such as brick dust but will not detect dyes or lead at levels that matter. Laboratory analysis is the only reliable check, which is why the practical defence is buying well.
See also buying-spices, spice-contamination and the-spice-trade.