Adulteration…an ingredient checklist

The global natural products industry faces a deluge of quality challenges. These become amplified when the focus is placed on herbal ingredients, given the quality-management minefield this ingredient segment represents all on its own. The architects of adulteration make it their business to understand the detection techniques in use by quality control personnel, devoting a substantial amount of their energy to finding ways around them. All too often the adulterant nobody would ever suspect is the one that traps unwitting organisations in the natural products space. But why?

The ethical element of industry, that is; commercial operators who promote better standards of quality, industry bodies fighting for what’s right (American Botanical Council, American Herbal Products Association, Health Food Manufacturers Association (UK), Complementary Medicines Australia, to name a few) along with various regulatory bodies; tend to be slower at stamping out adulteration than the rate at which engineers of the same adulteration are pushing out new techniques of trickery.
The term ‘adulteration’ is commonly in use as a catch-all to describe numerous adulteration-‘esque’ techniques that, when examined further, can be individually distinguished by their inherent characteristics and acknowledged by a specific definition. This article attempts to drill down to the layers beneath the surface, giving clarity on some unique characteristics of each technique, why they might be used, how they can be difficult to unveil, as well as a case-study or two with some tips on what to look out for in certain circumstances. Adulteration can be further dissected into substitution, fortification, depletion, as well as unintended instances of adulteration that generally involve mistaken identity.

Substitution is when one ingredient is blatantly substituted for or replaced by another ingredient or substance. A number of classic cases exist for this method of duping the user.
Take the purple food colouring, dye amaranth. Known in many countries by its food additive code E123, the colourant has unfortunately found a place as a substituent for Bilberry extract. Dye amaranth was banned in the US in the 1970’s and is heavily restricted in most other markets, making notable the related safety concerns for this method of substitution. Techniques to detect substitution of Bilberry with dye amaranth have been available for a while now, but like all good detection techniques, they’re only as valuable as our readiness and willingness to use them. Due to its high commercial value, Bilberry has seen many and varied methods for supplanting by low-cost substitutes. You can read more about this along with recommended simple detection methods in a 2014 paper on Bilberry adulteration detection, published in the journal Fitoterapia. In this paper, it was discovered that no less than 10 commercially available, less costly materials could be quite readily disguised as Bilberry and unless analytical techniques were sufficiently rigorous, this ‘bait-and-switch’ practice would continue unnoticed. Common substitutes included other berry materials that share one or more components of their chemistry with Bilberry. In somewhat more bizarre cases, materials that were unrelated to Bilberry entirely were used as substitutes, such as Black Rice or Soy. The reality is that many plant species share common constituents, so if a high-demand material can be swapped out for a less expensive alternative (less expensive since its relative commercial appeal is much lower), then Presto! We have a candidate for substitution.

Fortification involves ‘topping up’ what is often a key active constituent and/ or quality marker in an ingredient. The intended purpose is to mislead quality control personnel into believing an ingredient naturally contains more of a key component than it actually does. An age-old example of fortification is the addition of synthetic caffeine to Guarana, or synthetic ascorbic acid to Acerola. Although each presents minimal safety risk as the synthetic varieties of these components are used widely in food preparations, the issue arises of the ingredient user having the impression that the quality standard of the product they receive is greater than it really is. It also introduces the challenge to those ingredient companies doing the right thing, who are forced to wrangle with low-cost competition operating on an entirely different quality plane. Should the provider of the fortified ingredient be forced to declare when these synthetic additives are used? Why would that ingredient provider be reluctant to disclose this information?

Depletion is the practice of removal of key therapeutic active constituents for some other primary purpose, and then supplying the remaining ‘by-product’ as the main ingredient. One stark example of such a practice is in the case of Milk Thistle extract. The components silybin A&B are to some extent removed from the crude material and go off in a different direction for pharmaceutical use in the treatment of liver disease. The leftover by-product is then supplied at a very low cost to the supplements market as ‘Silymarin extract’. Historically, analytical procedures for quantitation of key Milk Thistle constituents would not detect when the product was silybin-depleted. It’s comforting to know at least in this case, analytical techniques are becoming more available to help identify when the herbal ingredient you’ve been sold is actually just a cheap by-product.

The challenge for industry in continuing to battle adulteration practices en masse is one that would appear insurmountable. To date, industry has been forced to deal with each technique on a case-by-case basis, developing detection methods that address the means of specific adulteration techniques head-on, but a blanket system for eliminating adulteration remains as elusive as ever. Ingredient users must demand quality, but with so much price competition on the global natural products stage the difficulty prevails in delivering a high-quality, authentic ingredient at a price the consumer is willing and able to pay.

Adulteration:

In food supplement circles, adulteration involves the inclusion of one or more substances to an ingredient or finished product, with the intent being to disguise the product as something it is not. Typically the inclusion of the adulterant is designed to make the product user believe the product is of an acceptable quality standard.
Often the practice is undertaken with malicious pretence, and is commonly motivated by the prospect of financial gain (otherwise known as Economically Motivated Adulteration).

Examples include:

Ginkgo spiked with Quercetin
Ginkgo adulterated withSophora japonica
Grapeseed being adulteratedwith Peanut husk, and otherprocyanidin-containing plants
Bilberry substituted for dyeamaranth
Bilberry substituted for soy hull
Bilberry substituted for blackrice
Bilberry substituted for almostany other anthocyanidin-containing berry
Korean Ginseng root beingsubstituted with AmericanGinseng
Korean Ginseng root being spiked with other, less costly Ginseng plant parts
Skullcap accidentally substituted with Teucrium spp.
Echinacea and the ongoingspecies distinction issues
Viburnum spp. being mistakenfor just about any other speciesof Viburnum.
This list really does go on….

Author: Ryan Gorman, Brand Director, Network Nutrition-IMCD

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