Coriander seed is the dried fruit of Coriandrum sativum, harvested at maturity, threshed, cleaned and graded. Two seed types are traded and they are not interchangeable. The larger, more spherical var. vulgare type is the mainstream culinary and grinding seed. The smaller, more oval var. microcarpum type carries a higher volatile oil content and is the type distillers buy for essential oil recovery. Ukraine grows predominantly the smaller-seeded high-oil type, which is why Ukrainian coriander is quoted more often against distillation demand than against culinary demand.
Unlike a leaf herb, coriander seed is a field-dried commodity handled with grain equipment. That changes the specification: moisture and admixture behave like grain parameters, the cleaning line is a grain cleaning line, and the microbiological and mycotoxin questions attach to field exposure rather than to a wet processing step.
Grades, cuts and calibration
Seed type and size. Specify the type and the sieve. A 1,000 grain weight or a screen size range is the practical way to write it; ‘coriander seed’ on its own can arrive as either type.
Volatile oil and linalool. Volatile oil is the primary value axis for the smaller-seeded type, and within that oil the linalool fraction is what a distiller or a flavour house is actually buying. Culinary buyers care about total oil and sensory character; distillation buyers care about oil yield and linalool percentage, and will pay against them.
Admixture, splits and damaged seed. Admixture is other plant material, stalk, chaff and weed seed; splits are broken fruit that has lost some of its oil to evaporation; damaged seed covers insect and mould damage. All three get a maximum. Splits matter more here than on most seeds, because a split coriander fruit has an open surface and loses volatile oil steadily.
Purity and foreign seed. A grain-style purity figure, plus a specific limit on toxic weed seed where the buyer’s own risk assessment requires it, plus stones and mineral matter. Optical sorting is what delivers a low number on a field crop; screening alone does not.
Seasonality and availability
Coriander is harvested in July and August in Ukraine, threshed and dried down in the field or on the farm, then cleaned and graded through the autumn. New crop is normally available from September, and carry-over from the previous crop competes with it until then.
Crop year is a price and a quality variable. Volatile oil content varies with season, and it declines slowly in storage, faster in split or damaged seed. A wet harvest raises the mould risk and can push a lot into a mycotoxin question that a dry harvest never raises. Ask for the harvest year in writing on every offer, and treat a lot with no stated crop year as carry-over until proven otherwise.
What the buyer checks at intake
- Seed type, crop year and origin declared, with the screen size or 1,000 grain weight against the contracted grade.
- Volatile oil content on the certificate of analysis, and the linalool fraction where the material is bought for distillation.
- Admixture, splits and damaged seed on a weighed sample, with foreign seed and mineral matter reported separately from plant admixture.
- Moisture at intake and again if the lot will be held, because a field-dried seed re-equilibrates with the store.
- Mycotoxin results where the buyer’s plan requires them, read against a proper sampling plan rather than a single grab sample, because mycotoxin distribution is heterogeneous.
- Salmonella on the panel. A field-dried spice with no kill step is a recognised route, and this is a food safety criterion, not a specification preference.
- Live insect check on arrival and again before use, because a seed with residual moisture in a warm store can support an infestation that was not present at loading.
Where it is used
Bakery is a large culinary outlet, particularly rye and mixed-grain breads, where whole or cracked seed is used for both flavour and appearance. Meat processing and sausage manufacture take ground coriander in seasoning blends. Pickling, curry blends and retail spice jars take whole seed.
Distillation is the other half of the market: coriander seed oil is a significant flavour and fragrance material, and the smaller-seeded high-oil types are grown for it. The oil and the extracted fractions sit under a different regulatory treatment from the whole seed, so a specification written for culinary seed does not transfer to an extraction contract without review.
Standards and routes
Coriander seed moves as a bulk-style dry good: 25 kg polypropylene bags on pallets, or big bags, in standard dry containers or curtainside trailers. Unlike leaf herbs it has a high bulk density, so the truck fills on weight and a full load is 22 to 24 tonnes.
The main constraint is plant health. A seed is plant material, so the consignment normally needs a phytosanitary certificate as well as the standard food chain documents; the requirement set is covered in the export documentation guide. Road corridors through Poland carry most of the volume to Germany and the Netherlands.
