Again, you have no idea what you are getting. ( see
http://cms.herbalgram.org/BAP/BAB/T...45&signature=1187bb2615cb9ea13e35487cccb850fc)
Known adulterants: The fact that this spice is frequently sold in powdered form (which renders identification to species by macroscopic visual inspection impossible) makes it more susceptible to mixing with extraneous, lower-cost botanical ingredients, starches, chalk powder, cassava, and synthetic dyes.32,37-40 A report has raised the issue regarding what appears to be the trade of turmeric roots that were pre-extracted and mixed with non-extracted roots. The spent roots were lighter, less dense, and of a red color different from the roots that did not appear to be pre-extracted. (R. Upton email communication to S. Gafner, April 16, 2018). Whole rhizomes of turmeric have also been found to be adulterated with species from the same genus containing curcumin, e.g.,
C. zedoaria.27,32,38,40,41
The first report of adulteration of
C. longa with
C. zedoaria and
C. aromatica was published in the 1970s.32
Curcuma zedoaria, a wild relative of turmeric, also sometimes known as white turmeric, is a plant easy to mix with turmeric powder due to its close resemblance and wide availability. The plant is indigenous to Bangladesh, Sri Lanka, and India, and is also widely cultivated in China, Japan, Brazil, Nepal, and Thailand.32,42 Adulteration has also been reported with
C. zanthorrhiza.43
Due to the high demand in international trade, turmeric powder has been subject to economically-driven adulteration with potentially toxic chemical compounds. Metanil yellow (sodium
3-[4-anilinophenylazo] benzenesulfonate) is a synthetic, non-permitted food color and additive, which has been used as a turmeric adulterant, since it mimics the color appearance of curcumin.37,44 Other dyes which have been cited as adulterants in turmeric are lead chromate,27,39,43 acid orange 7 (sodium 4-[(2
E)-2-(2-oxonaphthalen-1-ylidene) hydrazinyl]benzenesulfonate),45 and Sudan Red G.46 Turmeric is also diluted with yellow soapstone powder, a natural mineral.
Extracts standardized to curcuminoids are among the fastest-growing herbal ingredients presently in the United States (Tables 1 and 2). Prices for natural curcuminoids from
C. longa are above $150/kg, about three times that of synthetic curcumin, which costs around $50/kg. This has given rise to unethical suppliers spiking natural turmeric extracts with synthetic curcumin (N. Kalyanam [Sabinsa] email communication, March 1, 2017).
3.2. Sources of information supporting confirmation of adulteration: Scientific papers from the 1970s and 1980s describe adulteration of turmeric with other
Curcuma species, starches, and dyes, and provide methodologies for their detection, but no commercial samples were evaluated in these papers.32,46,47
In 2004, three market samples of turmeric powder brands in the Indian market were analyzed based on genetic profiling (Random Amplified Polymorphic DNA [RAPD] analysis) and compared to genuine powders of
C. longa and
C. zedoaria. The analysis revealed the presence of more
C. zedoaria (wild species) powder than
C. longa (the common culinary turmeric) powder, even though the curcumin levels of the samples met the quality standards.42
In 2011, six samples of turmeric powder procured from a local market at Calicut, Kerala, India were analyzed using two Sequence Characterized Amplified Region (SCAR) markers, a method to determine the identity of turmeric based on DNA markers. Both markers detected the presence of adulteration with
C. zedoaria or
C. malabarica in four market samples and in simulated mixtures, i.e., samples of turmeric powder and the adulterants made at different concentrations.48 In 2015, one out of 10 turmeric samples analyzed by DNA using single nucleotide polymorphisms (SNPs) that discriminate between
C. longa and
C. zedoaria was shown to be adulterated with
C. zeodaria.49
The Bureau of Indian Standards suggests a minimum of 3% curcumin for powdered turmeric, whereas the mandatory Prevention of Food Adulteration (PFA) Act of 1954 does not specify any minimum curcumin limit.44 Despite the regulations in place in India, the quality of turmeric products on the Indian market is highly variable.
In 2008, a report showed turmeric adulteration and detected the presence of organic dyes, such as metanil yellow (1.5–4.6 mg/g), Sudan I (4.8–12.1 mg/g), and Sudan IV (0.9–2 mg/g) in loose turmeric and chili samples from city markets across India. The curcumin content in turmeric and mixed curry powder samples ranged from 6.5 to 36.4 mg/g and from 0.3 to 1.9 mg/g, respectively.37
In a 2013 report, four commercial samples of whole dried rhizome turmeric were collected randomly from four different areas of the spice market of Allahabad, India, and analyzed for possible adulteration using laser-induced breakdown spectroscopy (LIBS), an atomic absorption technique providing signatures of each element. The analysis demonstrated that one of the four samples had spectral signatures corresponding to lead (Pb) and chromium (Cr), suggesting they might contain lead chromate as an adulterant providing color to make them more attractive to consumers.27
In another study, food samples from the unorganized sector in West Bengal, India were tested. The unorganized sector is comprised of private enterprises owned by individuals or households that produce or sell goods and services, operate on a proprietary or partnership basis, and employ less than ten workers. Fifty-eight samples of a total of 253 collected (20.94%) contained metanil yellow, with 32.95% of the turmeric powder specimens and 31.32% of the
laddoo(ball-shaped traditional Indian dessert made with flour, milk, sugar, and turmeric) samples containing metanil yellow. No significant contamination of metanil yellow was found in
besan (a flour made from a variety of ground chickpea) samples.50
A recent review on ground turmeric as a source of lead exposure in the United States was conducted by researchers at the Department of Environmental Health, School of Public Health at Boston University. The review focused on the contamination of turmeric with lead (with high lead levels likely coming from the addition of lead chromate) in products imported from India and Bangladesh to the United States. According to the authors, spices, food, and dietary supplements in the United States may be extensively adulterated with lead to enhance its weight, color, or both.39 In 2011 and 2012, the authors purchased 32 samples of turmeric from mainstream grocery stores, specialty stores, and ethnic markets throughout the greater Boston area and found detectable levels of lead in all of the samples, with a median concentration of 0.11 μg/g (range: 0.03-99.50 μg/g), using inductively coupled plasma-mass spectrometry. The authors cite several FDA enforcement reports from 2011 to 2014 showing 13 lead contaminated turmeric brands recalled (voluntarily) in several US states. In 2016, seven brands of turmeric were recalled because of elevated lead levels, as well as five brands of curry powder, amounting to 337,000 pounds.39
Most recently, 38,000 pounds of turmeric that were distributed to Florida and New York by Spices USA, Inc. were recalled because of elevated lead levels.51 The FDA issued an import alert of lead poisoning on September 26, 2016, which allows ports to detain future shipments from specific importers, targeting turmeric from Pran (Bangladesh), Visakarega Trading (India), and Indo Vedic Nutrients (India).51
In 2014, Harvard University researchers reported lead concentrations of up to 483 μg/g in turmeric samples collected from 18 households in rural Bangladesh, a country where the permissible level of lead in turmeric is 2.5 μg/g.39,52 A newspaper article (
Times of India, published May 10, 2010) reported a raid by the Indian Food and Drug Authority in 2010, with inspectors discovering over 100 bags of raw turmeric contaminated with lead chromate at a spice manufacturing plant.53
The issue of adulteration of natural curcumin with synthetic curcumin was first reported in 2011, when EuroPharma (Green Bay, WI), a US manufacturer of natural turmeric extract supplements, considered the possibility of commercially available curcumin supplements made with a lower-cost synthetic version and began working with University of Georgia on tests using radiocarbon dating techniques to analyze curcumin products on the market to determine the percentage that contained synthetic versus natural curcumin, or a combination of both.23,54
After the 2011 report by EuroPharma, other suppliers initiated strategies to identify products adulterated with synthetic ingredients23,54,55 and, in some instances, apparently prompted industry members to take legal action. On May 26, 2015, Sabinsa Corporation's parent company Sami Labs Limited (Bangalore, India), filed a criminal complaint with the chief magistrate, Bangalore and the Peenya police department, Bangalore, against Bayir Extracts Private Limited, Bangalore, India for knowingly supplying adulterated turmeric oleoresin with a forged Certificate of Analysis.56,57
The 14C testing of five commercial samples of curcumin sold by Bayir for export to the U.S. showed that four of the materials contained curcumin that was 32-45% synthetic, while the fifth sample was 100% natural.57 Using the same testing approach, materials from another supplier (Biotikon®, Gorxheimertal, Germany) were also found to contain significant amounts of synthetic curcumin.58
3.3. Accidental or intentional adulteration: Turmeric is likely one of the spices most frequently adulterated because of its widespread use and high cost. In some situations, the use of
C. zedoaria could be a case of mistaken identity and qualified to be an accidental adulteration due to human error. But the uses of cassava, talc powder, starches, yellow dyes, minerals and synthetic curcumin are clearly intentional and constitute economically-motivated adulteration.
3.4. Frequency of occurrence: Adulteration of turmeric powder commonly occurs with synthetic dyes, zedoary root, starch, and cassava in food ingredients, and also with synthetic curcumin on turmeric curcumin used as an ingredient in dietary supplements. The use of dyes in unbranded turmeric powders sold in bulk is prevalent in different regions in India. The frequency of adulteration of
C. longa with
C. zedoaria is not known. Morgan et al.59 suggest that adulteration with
C. zedoaria is rare, but a large market sample analysis has yet to be performed.
The presence of
C. zedoaria was detected in all three samples of popular turmeric powder products tested.42 In another study, one out of 10 branded samples from an Indian market showed the presence of zedoary and starches although the label claimed nothing other than turmeric powder.49
Thin-layer chromatography (TLC) analysis of market samples (of turmeric, chili, and curry purchased in Lucknow, India) showed the presence of the food dyes metanil yellow (1.5–4.6 mg/g), Sudan I (4.8–12.1 mg/g), and Sudan IV (0.9–2.0 mg/g) in loose turmeric and chili samples; the occurrence of the Sudan dyes was limited to the chili samples.37
In a more detailed study by the same group, 712 commercial samples in India were tested using a two-dimensional high-performance thin-layer chromatography (HPTLC) method. None of the branded samples (N =100) showed the presence of artificial color, but 105 (17.2%) of the non-branded samples (N = 612) of turmeric powders were dyed with metanil yellow.44
Four samples of whole dried turmeric rhizome collected randomly from four different areas of the spice market of Allahabad (India) were analyzed directly by the LIBS technique for a complete profiling of elements present in the samples. Three samples were found to be authentic, while one sample had a bright yellow color. This latter sample was found to be adulterated with lead II chromate dye.27
Analysis of 253 food samples, consisting of three different types of food items —turmeric powder, laddoo, and besan — were tested for the presence of metanil yellow. Fifty-eight out of the 253 samples collected, i.e., 20.9%,were found to contain metanil yellow with 36.2% of the positive samples below the maximum permissible limit and 63.8% above the maximum permissible limit of 100 mg/kg, as specified in the Prevention of Food Adulteration Act of India.50,60 No metanil yellow was found in any food samples prepared from the food items (turmeric powder, laddoo, and besan) produced by the organized sector, i.e., those companies that are registered with the Indian government and follow its rules and regulations.50
The practice of adulteration with dyes in India is regional, and turmeric from poorer sectors in the Indian state of West Bengal has been found to contain metanil yellow more often than turmeric from the more affluent regions of the state.50
The occurrence of adulteration of
C. longa with other
Curcuma species as lower-cost substitutes in the marketplace has been mentioned in many publications since the 1970s,32,38,49 but reports of the analysis of samples of branded commercial turmeric products are limited. In one report, one of the 10 samples analyzed by DNA barcoding showed the presence of
C. zedoaria DNA. The 10 samples were from popular brands of turmeric powder procured locally from Kozhikode (Kerala state, India). Each of the 10 samples was produced by a different company.49 Another report using
RAPD markers to distinguish among
Curcuma species found all three samples analyzed were adulterated with
C. zedoaria.42 Finally, an investigation from 2014 into the quality of 39 commercial turmeric samples for food, dietary supplement and cosmetic use sold in supermarkets and retail stores in the United Kingdom (27), India (8), the Netherlands (2), Iceland (1), and Greenland (1) labeled to contain
C. longa (34),
C. amada (1),
C. aromatica (2),
C. zanthorrhiza (1), and
C. kwangsiensis (1) by HPTLC showed that three products did not contain any bands, one turmeric product was adulterated with
C. aromatica, and one product from India contained merely curcumin, with little to no demethoxy- and bisdemethoxycurcumin.41
As noted above, a more recent practice is the use of synthetic curcumin to adulterate turmeric extracts claiming a specific curcuminoid content. Since synthetic curcumin is of much lower cost, companies that produce all-natural ingredients have reported that fraudulent suppliers of turmeric extracts containing synthetic curcumin are able to offer materials at lower prices (N. Kalyanam [Sabinsa] email communication, April 2, 2017).
As stated in section 3.2 above, four out of five samples from one supplier were found to contain synthetic curcumin.57To date, no report with test results of a larger set of commercial samples is available to confirm the frequency of adulteration with synthetic curcumin, and its geographic distribution.
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