Authenticity check for turmeric
How to check the quality of your raw material
Feb 2023. Turmeric is trending as a superfood and has found its way into a wide variety of food and nutritional supplements (NEM) as an ingredient. Well-known examples include spices, capsules, teas and shots. However, with increasing demand and price development, the risk of adulteration is also increasing. To protect yourself from misinformation and the purchase of raw materials of inferior quality, we give you helpful tips on how to check the safety and authenticity of your raw materials and products.
Turmeric as a trendy superfood
Especially as a spice, tumeric is trendy. According to Joint Research Centre (JRC) of the European Commission (page 1, fig. 1) 15,000 tons have been imported into the EU in 2019. This puts turmeric in 4th place among spice imports. However, it is not only used for its appearance and taste, but also for its digestive properties, e.g as a dietary supplement. Turmeric is known through Ayurveda and especially through curry, in which it is a main ingredient. Due to its colouring properties, it is used as an extender for the even more valuable saffron, but is itself being adulterated by the increasing demand.
Analyses under food safety aspects
Even the intense yellow colour can be manipulated, a fact that was already known before the introduction of the Europe-wide Rapid Alert System (RASFF) and which is why tests for forbidden dyes such as Sudan dyes or lead chromate have already been carried out regularly in the past. In addition, regular testing for pesticides (also ethylene oxide), mycotoxins (Aflatoxin) or heavy metals or microbiological parameter is recommended, which is supported by the findings of the RASFF (please also see our Food Legislation News).
In addition to the parameters mentioned, mineral oil hydrocarbons are playing an increasing role. Their legal regulation is currently being discussed in the EU and EFSA. The toolbox published by the food association (in German) can help to identify sources and thus make them influenceable as well as to reduce and at best eliminate possible findings.
Analyses under food fraud aspects
The EU has published a report according to which 17% of the analysed herb and spice samples were suspicious under food fraud aspects. For turmeric it was 11%. Besides so-called filling materials such as starch, the active ingredients of turmeric, the curcuminoids, are important authenticity parameters. Especially curcumin as the main ingredient is determined quantitatively. Demethoxycurcumin and bisdemethoxycurcumin are also of interest. The "natural origin" of curcumin is a popular advertising claim, but curcumin can also be produced by chemical synthesis, so that the curcumin content alone is not sufficient to prove its natural origin. For this purpose, the isotope carbon 14 or C14 for short is used, which has different contents compared to synthetic and natural curcumin.
Another important possibility for authenticity testing is 1H-NMR. Active ingredients such as curcuminoids can be analysed in plant extracts or food supplements. NMR is also a generally applicable method that can be used not only for turmeric but also for other ingredients such as piperine or ginkgolides. In addition, NMR allows the recording and comparison of spectra from different samples of the same plant origin. A doubted sample can be compared with an authentic sample. The spectra of authentic references are collected in databases and used for comparison with samples of unknown reference.
Please contact us
Do you have questions about the analysis of turmeric? We will be happy to advise you on your specific raw materials and products. Simply contact your personal account manager or our expert, Dr Rainer Rickert. We are looking forward to your enquiry.
