What Can We Do About Adulterated Herbs and Spices?

Spices and herbs are at the forefront of food fraud around the world. Most herbs and spices are grown in developing countries, often by small farmers and villages rather than the enormous industrialized farms often used for food production in the developed world. Many spices and herbs require fairly involved processing before they can reach distant markets, or are otherwise labor-intensive to produce, which keeps their prices high compared to other crops. Spices provided the economic backbone of world-spanning empires and, even with modern technologies continuing to make their supply a less and less daunting endeavor, are a $4 billion trade. Protecting that trade requires constant vigilance.

Herb and spice adulteration takes many forms. These items can be adulterated with artificial dyes, fillers, and cheaper cousins and synthetics. Each of these fraudulent methods serves to reduce the cost associated with herbs and spices by replacing some of their weight or volume with a less expensive alternative, often with additional measures to conceal the addition. Many factors contribute to herbs and spices being particularly tempting targets for this sort of treatment:

Expensive spices often have close relatives that are less expensive to produce at the cost of lower quality, such as cassia for cinnamon and artificial vanillin for natural vanilla. Slipping some of the less expensive version into the supply is easy, and these additions can be hard for outsiders to notice. Herbs can be adulterated with less aromatic parts of the same plant, defying genetic tests as well.
Distant consumers may not be particularly well acquainted with high-quality spices, making low-quality products easier to conceal at the consumer level.
Particularly with spices and herbs grown in developing countries by multitudes of small farmers rather than a small number of large, industrialized growers, supply chains can become very difficult to trace, making it hard to assign culpability for adulteration.
Spices and herbs are worth a great deal more per unit than other crops, making the potential profit from adulteration far higher than in some other sectors of the food supply.

Agricultural goods in general, and spices and herbs in particular, have complicated supply chains that involve multiple iterations of harvesters, processors, wholesalers, shippers and retailers. Any link in that chain could choose to pad its profits by selling adulterated product, and without adequate product inspection and testing, all subsequent links then pass this product to the consumer, reducing the product’s and the seller’s reputations and potentially opening everyone involved to legal reprisals. Perhaps more importantly, although all adulteration results in inferior products, not all adulteration is safe. Some unscrupulous suppliers use ground nut shells as fillers, creating risks for consumers with allergies. Others use starches, which can prevent diabetics from making informed decisions about their sugar consumption and lead to blood sugar spikes. Most famously, use of potentially dangerous Sudan red dye in dried chili products to disguise inferior quality in the early 2000s led to product recalls in Europe.

It is important for vendors to protect against these risks by asking the right questions and having the right answers. Having as much information as possible about one’s supply chain is critical. Insisting that suppliers provide thorough descriptions of their product, including species, kinds of processing used, and content of active chemicals such as piperine for black pepper and cucumin for turmeric, helps prevent some forms of adulteration and fraud. Knowing where norms or enforcement in a supply chain might otherwise be lacking provides advance knowledge of places that might require stronger scrutiny. Understanding one’s market well enough to know when a supply is arriving at an unusual time or for an unusually low price can help authorities detect frauds before they can spread. For products that have already undergone some manner of processing, knowing when that processing is unusual, such as a spice that’s ground too finely, can help one detect when something is amiss.

Although these protective measures can keep fraudulent goods out of the supply chain, they cannot provide the same level of assurance as laboratory testing. Chemical tests can determine whether the content of common active chemicals matches what is expected, distinguishing inferior or adulterated products from the genuine article. Liquid chromatography and tandem mass spectrometry (LC-MS/MS) can provide detailed molecular profiles of test samples, revealing whether anything unusual is present and whether the expected constituents are present in expected amounts. Genetic sequencing can provide similar information at the botanical level, including the identity of any biological adulterants, and is particularly critical for detecting whether a related plant has been used. Microscopic examination can reveal physical traces, such as use of stems to extend leaf-based crops and use of dyes to conceal inferior saffron, that would defy genetic tests. Implementing these tests at various points in a supply chain, and making sure that the samples used for the tests are as representative as possible, can help authorities zero in on where, exactly, something untoward entered the chain, and keep herbs and spices genuine, high-quality and safe into the future.

For more information on Thermo Fisher Scientific’s food-testing technology and particularly technology for identifying the species present in plant-based samples, visit our food authenticity pages.