The Role of Rapid Test Kits in the Detection of Peanut
and Almond Residues in Cumin and Spice Blends
Anthony J. Lupo, Director of Technical Services • Issued February 2015
Background
In recent months there have been several cumin recalls involving seasoning blends containing high levels of undeclared peanut, and in some
cases, detectable levels of almond in the United States. This has
resulted in significant concern in several segments of the food and
ingredient industry related to the safety of their incoming raw
materials, and the tools available to accurately test them for these
undeclared residues. The purpose of this document is to answer those
questions that are currently top-of-mind for many in industry and to
offer assistance with the tools and services that Neogen can provide.
How much risk does this pose to the allergic consumer?
Frequently Asked Questions
• How did peanut and almond residues get into cumin and spice
blends?
• How high are the levels of peanut and almond being found in cumin
and spice blends?
• How much risk does this pose to the allergic consumer?
• What tools are available for the detection of peanut and almond residues in cumin?
• How can the food industry be assured that these methods of detection are true peanut and almond contamination and not simply
interference or cross-reactivity?
How did peanut and almond residues get into cumin and spice
blends?
While there is no current direct evidence as to how these ingredients
became contaminated, there are currently two working theories.
• The ingredients were adulterated for the purposes of economic gain
with an inexpensive extending agent that contained significant levels
of allergenic protein (e.g., peanut shells)
• In samples with moderate to low level (2.5–25 ppm) contamination, it is possible the ingredients may have become contaminated
through commingling or accidental cross-contact with peanuts or
almonds during processing, shipping, or storage.
How high are the levels of peanut and almond being found in
cumin and spice blends?
• Positive samples analysed by the Neogen laboratory services team
in Lansing showed contamination levels ranging from 4.6 ppm total
peanut to greater than 5000 ppm total peanut. However, it should
be noted that several of the samples submitted to the laboratory
tested with no detectable amounts of peanut or almond.
• Neogen is aware of samples tested in other laboratories in the
USA with reported levels as high as 105,000 ppm total peanut.
• It is believed that ingredients testing at very high levels (hundreds or
thousands of parts per million) puts the allergic consumer at significant risk. Even if the ingredient is present at a relatively low inclusion
rate like a spice, the dilution effect is not sufficient to consider it safe
for the allergic consumer. Such levels even when diluted in finished
foods are still well above published reference doses for many peanut
allergic individuals.
• Ingredients testing at moderate to low levels (2.5–25 ppm) will be
significantly diluted when found in foods at typical spice blend inclusion rates. A proper risk assessment should be conducted to
determine if the level of risk is acceptable
What tools are available for the detection of peanut and almond residues in
cumin?
Neogen has analysed its range of test kits
and found them to be suitable for this purpose. This included an evaluation of Neogen’s AOAC-validated Veratox® for Peanut Allergen, an enzyme-linked
immunosorbent assay (ELISA) in a microwell format that fully quantifies the amount of peanut residue detected in parts per million (ppm),
and Veratox for Almond Allergen, an identical test for the detection of
almond residues. Also evaluated were Neogen’s Alert® brand microwell
tests for peanut and almond. The Alert tests are based on the same
technology of the Veratox tests, but screen samples at 5 ppm instead
of fully quantifying.
For companies unable to carry out on-site testing or for further analysis,
Neogen offers a UKAS accredited rapid laboratory testing service
for Almond and Peanut at its location in Ayr Scotland. Laboratory
testing is also available in Lansing, USA from Neogen. Our allergen
testing service is available for the analysis of food matrices, CIP
rinse waters and environmental swabs using ELISA methods.
Neogen is prepared to support the food industry with a spectrum
of tools and services that have proven reliable for the detection
of peanut and almond residues in cumin and spice blends.
• The same samples analysed on several brands of test kits each
with different antibodies exhibit similar results. Multiple test kits
reporting similar results are rarely wrong.
• Well-known laboratories have taken positive samples and separated the proteins using gel electrophoresis and transferred those
proteins to nitrocellulose. They were then challenged with human
IgE antisera from known peanut allergic individuals and binding of
those antibodies in molecular weight regions consistent with known
peanut allergens.
• All evidence supports that these are true positive results.
Conclusion
How can the food industry be assured that these methods of
detection are true peanut and almond contamination and not
simply interference or cross-reactivity?
• It is very uncommon for an antibody-based test kit to exhibit such
strong positives (>5,000 ppm) when the cause is cross-reactivity
or matrix interference. Typically these manifest in very low level
positive results (<10 ppm).
• There are several examples of these ingredients reporting no
detectable peanut or almond residues. Typically interference or
cross-reactivity manifests itself in all samples of this type
making non-detect results not possible.
Depending on your needs, Neogen is prepared to support the food
industry with a spectrum of tools and services that have proven reliable for the detection of peanut and almond residues in cumin and
spice blends.
To be clear:
• Although evidence suggests adulteration, this has not been proven.
• Neogen test kits have shown to be fit for purpose in this application.
• A full risk assessment should be conducted before declaring any
product believed to be contaminated safe for consumers.
• When positive results are diluted they exhibit a linear dose response.
False positives do not dilute linearly.
Neogen offers complete food safety solutions:
Food Allergens and Adulteration • Foodborne Bacteria • Natural Toxins
Hygiene • Drug Residues • Dehydrated Culture Media
+44 (0) 1292 525 627
[email protected] • www.neogeneurope.com
© Neogen Corporation, 2015. Neogen, Alert, Reveal and Veratox are registered trademarks of Neogen Corporation, Lansing, MI 48912 USA.
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