Turmeric Whole Rhizome Powder (Curcuma longa)

Turmeric whole rhizome powder is the cured, dried and milled rhizome of Curcuma longa L., family Zingiberaceae, and nothing else: no solvent has touched it and nothing has been concentrated out of it. That single fact separates this article from the curcumin 95% concentrate Thovek also supplies, and the two are bought by different formulators for different reasons. The concentrate delivers a defined dose of three purified colouring principles. The whole powder delivers the rhizome as the plant assembled it — curcuminoids together with the volatile oil, starch, fibre and minor polar constituents that a solvent-and-crystallisation route strips away. A brand writing whole-herb, full-spectrum or traditional Ayurvedic language on the front of a pack needs this material, because a 95% extract cannot honestly carry those words. Curcumin is the dominant marker. Assayed commercial turmeric powders average about 3.14% curcumin by weight, and all three curcuminoids are present in their natural proportions: curcumin (CAS 458-37-7, C21H20O6, MW 368.4), demethoxycurcumin and bisdemethoxycurcumin. Alongside them sit 3–7% essential oils in which turmerone, germacrone, atlantone and zingiberene are the principal components — the fraction that gives whole turmeric its aroma and that a purified curcuminoid crystal no longer has. Cultivar, curing method and rhizome maturity move the curcuminoid figure more than anything a processor does, so Thovek states a measured HPLC number per lot rather than a nominal one. Turmeric is also among the most adulterated commodities in the spice trade, and buyers should treat that as a purchasing specification rather than a footnote. Lead chromate, a bright yellow pigment used to deepen colour, has been found as a turmeric adulterant at contamination levels up to 500 times the national limit in Bangladesh, and metanil yellow (acid yellow 36) is treated by the British Food Standards Agency as an illegal dye for use in foods. Every Thovek lot is screened for both and for Sudan dyes, with the results printed on the certificate of analysis. The material is a free-flowing orange-yellow to deep ochre powder with the warm, earthy, faintly bitter character of properly cured rhizome; the standard cut is 100% through 60 mesh, with 80 and 100 mesh available. It is insoluble in water and disperses rather than dissolves, so it suits capsules, tablets, opaque premixes and seasoning systems rather than clear beverages. It stains persistently, which is a plant-hygiene consideration for any co-manufacturer running pale-coloured lines. The powder is plant-derived and suitable for vegan and vegetarian claims, is free of milk, egg, soy, fish, crustacean, mollusc, peanut, tree nut, sesame, mustard, celery, lupin and gluten-bearing cereals, and is non-GMO. Because it is the spice itself rather than a preparation of it, turmeric powder moves as a food commodity in most destinations while the oleoresin and the isolated curcuminoids are handled under different rules — and, as the classification note below sets out, under a different tariff chapter. Steam-sterilised and ethylene-oxide-free grades are available where microbiological limits are tight.