Two lots of cumin can carry the same price and differ by fifteen percent in usable yield. Two lots of turmeric powder at the same price can differ by half in colour strength. The difference is never magic; it is a specification the cheaper seller did not mention and the buyer did not ask for.
Here is what each of the main specifications means, and — more usefully — which ones you should actually care about, given what you do with the spice.
Moisture content
Applies to everything. Moisture is water you pay for at spice prices, and it is also the precondition for mould, caking and insect activity in storage. Most whole spices sit sensibly somewhere in the 10–12% range; below that, aromatic spices begin to crumble and lose volatile oil; above it, storage life collapses.
Care a lot if: you store for more than a few weeks, or you are buying whole spice in the monsoon.
Purity and foreign matter
Quoted as a percentage — 98%, 99%, 99.5% machine-cleaned. The remainder is stone, stalk, chaff, dust and other seed. On a seed spice like cumin or coriander, this is the number that decides whether the lot is genuinely cheap.
Care a lot if: you grind. Every point of foreign matter is either a cleaning pass you have to run or grit in your finished product.
Bulk density (g/l, "GL")
Chiefly a pepper specification. Black pepper trades at 500, 550 and 580 g/l; white pepper at 600 and above. Higher density means heavier, more mature berries, more piperine and better grinding yield. It moves pepper price more than origin does.
Care a lot if: you buy pepper at all. Any pepper quotation without a GL figure is incomplete.
Screen size
The cardamom specification. Pods are screened to 6.5, 7.0, 7.5 or 8.0 mm bold. Larger pods look dramatically better in a retail pack or gift tin and command a real premium; for grinding into masala, paying that premium is money burnt.
Care a lot if: your customer sees the whole pod.
ASTA colour value
The colour strength of dried chilli and paprika, measured on a standard scale. It is independent of heat: Byadgi chilli gives deep red colour with mild pungency, while Teja gives heat with less colour. Buying high-heat chilli when you needed colour is one of the most common and most expensive mismatches in the trade.
Care a lot if: the visual redness of your product matters, or you extract colour.
Curcumin content
The turmeric specification, typically 2%, 3% or 4%+. It drives both colour and the health positioning premium brands and extraction buyers pay for. Commercial masala grades sit lower; extraction buyers will not look at low-curcumin material.
Care a lot if: you sell turmeric on colour or on health claims.
Volatile oil content
The measurable version of aroma, relevant to clove, cardamom, cassia, star anise, nutmeg and dry ginger. It is the specification that catches old or badly stored stock, which can look perfectly acceptable while being aromatically dead.
Care a lot if: aroma is the point of the purchase — tea premix, garam masala, extraction.
Headless and whole-flower percentage
Cosmetic specifications with real commercial consequences. Headless clove and broken star anise grind identically to intact material and cost noticeably less — but they look poor in a transparent retail pouch. Match the specification to whether the customer sees the spice.
Ash and acid-insoluble ash
Total ash indicates mineral content; acid-insoluble ash indicates sand and soil specifically. High acid-insoluble ash in a ground spice is a straightforward adulteration signal.
Care a lot if: you buy ground spices from anyone you have not verified.
Aflatoxin, pesticide residue and microbiology
Safety rather than quality specifications, and the ones with legal consequences. Aflatoxin is the principal concern in dried chilli and nutmeg; microbiological load matters in ground spices going into ready-to-eat products; pesticide residue limits bind on anything export-bound.
Care a lot if: you are a food processor, an exporter, or supplying an institutional buyer with an audit.
Species and identity verification
Two cases where getting it wrong is genuinely serious. Star anise: Illicium verum is the spice, while the visually similar Illicium anisatum is toxic. Cinnamon: true cinnamon (Cinnamomum verum) and cassia are both legitimate products, but they differ sharply in coumarin content and in price, and they are routinely sold interchangeably.
Care a lot if: always, on star anise. On cinnamon, whenever a customer or a regulation specifies which one.
How to turn this into a better enquiry
A specification-shaped question gets a specification-shaped answer. Instead of "price for cumin?", send: "1,000 kg Indian cumin, 99% machine-cleaned, singed, moisture under 10%, delivered Tejgaon, sample required before order."
You will get comparable quotations from everyone you send it to, and the suppliers who cannot answer in those terms have told you something worth knowing.
Every product page on this site lists the governing specification for that spice, and our quality and compliance page sets out what we declare per consignment and what testing we can arrange.
About the author. M/S S.S Trading is a spice importer, supplier and trading house at Shop No. 100, 5 No. Gulbodon Super Market, Moulvi Bazar, Dhaka-1211, Bangladesh, run by Tamim Hossain (Sabuj). We publish what we know about grading and buying because better-informed buyers are easier to trade with.