What is Saffron?
Saffron is a spice made from the dried stigma (part of the flower) of the saffron plant (Crocus sativus). You can see the red stigmas in the pictures.
Why is Saffron Vulnerable to Food Fraud?
Genuine saffron is harvested by hand, highly prized for its colour and flavour and very expensive. In fact, it is the most expensive spice and costs between USD $1,100 to $11,000 per kg. The international saffron market was worth US $430 million in 2018.
Saffron trade is complicated. Saffron’s most important growing areas are in Iran, Greece, Morocco and India. Afghanistan and Spain are also important sources of saffron. Saffron labelled Spanish is mostly grown in other countries but packed in Spain. Iran accounts for most global production at 90% – 93% but only accounts for 40% of direct global exports, according to the report (confusing!), apparently because the Iranian saffron is resold by other countries.
With so much of its production in one country, and with a short harvesting season, saffron supply is extremely vulnerable to weather events. For example, there was a tripling of prices from 2006 to 2009 because of heavy frost in Iran in 2007. Climate change is a threat, with increased moisture in some areas leading to more fungal plant diseases, and drought in other areas limiting yields.
Saffron is one of the most frequently adulterated foods. Powdered saffron is more at risk than whole saffron.
The biggest food safety issue with saffron fraud is probably the use of synthetic dyes to boost the colour of fraudulent whole saffron and saffron powder. Sudan I-IV and Rhodamine B dyes have been found in saffron and are considered potentially genotoxic and carcinogenic.
Adulterants in Whole Saffron
Here are some of the things that are added to saffron to fraudulently increase its value.
- Parts of saffron flowers, including the yellow style and the white style.
- Filaments from other plants, including corn fibres, safflower stigmas, calendula stigmas, pomegranate fruit fibres
- Filaments from other sources including silk. Adulterant filaments may be dyed with plant dyes including beetroot, pomegranate, fruit peel.
- Liquids that are added to increase weight, including oils, glycerin and honey
- Dyes and aroma compounds as listed below
Adulterants in Saffron Powder
Here are some of the things that are added to saffron powder to fraudulently increase its value.
- Turmeric powder
- Paprika powder
- Ground seeds of sweet fennel, or annatto
- Dried marigold flowers
- Gardenia (Cape Jasmine) extract, for their crocetin esters which are also in saffron
- Natural dyes from flowers and roots
- Artificial dyes including erythrosine, ponceau 4R, tartrazine, Sudan dyes, magenta III and rhodamine B
- Safranal, which is a synthetic aroma compound
Also, there are historical reports of fillers added for increasing the product’s weight, including chalk, gypsum and heavy spar (barium sulfate)
Other Types of Fraud (Non-Adulteration-Type Food Frauds)
- Selling Philippine saffron or “saffron flowers” as if they are real saffron (C. sativus). They are instead safflower or kasubha.
- Exhausted saffron sold as whole saffron
- Coloured paper shreds sold as saffron
- Provenance fraud, in which the geographical origin of the saffron is misrepresented
Testing is a challenge. Microscopic inspections can be done on powdered as well as whole saffron, but they are time-consuming and expensive. In addition, visual examinations won’t necessarily recognise adulteration with colourants or safranal.
Some DNA-based tests struggle to differentiate safflower from saffron, because they are closely related. DNA tests also don’t find safranal or dyes. Spectroscopic methods can be simple and quick but they are not very sensitive and won’t pick up all adulterants. There are many other authenticity test methods, each with its own challenges. It is recommended that a suite of complementary tests be used to cover all types of adulteration and fraud. Provenance testing has been successfully done using stable isotope methods.
This piece was orginially published in The Rotten Apple, a weekly newsletter about food safety, food fraud and sustainable supply chains.