How Is Caviar Made? From Sturgeon Farm to Sealed Tin

By Alex Beleaev, Founder of Beleaev Caviar & Gourmet. Last fact check: 2 September 2026.

Commercial disclosure: Beleaev sells caviar. This article distinguishes official standards from production practices that can vary between farms and processors.

The short answer

Caviar production begins with raising sturgeon until the eggs reach the required stage. Producers assess the fish and roe, separate and clean the eggs, grade the batch, add food-grade salt, pack it under controlled conditions and maintain a documented cold chain. The tin is then marked through the CITES traceability system.

The exact method varies by species, farm, jurisdiction and whether the producer uses non-ovulated or ovulated eggs.

What product does the international standard cover?

Codex CXS 291-2010 applies to granular sturgeon caviar made from eggs of fish in the Acipenseridae family. It covers species in four genera, Acipenser, Huso, Pseudoscaphirhynchus and Scaphirhynchus, as well as hybrids of those genera.

The standard defines caviar as fish eggs from this family treated with food-grade salt. It allows non-ovulated eggs and appropriately treated ovulated eggs from aquacultured sturgeon.

Source: Codex standards catalogue, CXS 291-2010.

Stage 1. Raising the sturgeon

Sturgeon farming is a multi-year process. The time to maturity varies with species, sex, genetics, water temperature, nutrition and farm management.

FAO's profile for Siberian sturgeon provides a documented example. It says females can reach puberty at about seven years in generally temperate farming conditions, earlier than the 12 to 20 years reported for females in cold natural environments.

This example should not be applied to every species. A claim that all caviar takes one fixed number of years is inaccurate.

Source: FAO cultured species profile for Acipenser baerii.

Stage 2. Identifying sex and assessing maturity

Young sturgeon do not show simple external differences that reliably identify sex. FAO describes several methods used in farming, including biopsy, hormone measurement and ultrasound.

Ultrasound can help producers identify females and assess gonad development without relying on appearance alone. A farm may combine imaging with other checks, depending on its method and local rules.

The old version of this article stated a universal number of scans and a universal two-to-three-week harvest window. Those claims have been removed because they were not supported as general standards.

Stage 3. Harvesting the eggs

There is more than one production route.

Non-ovulated eggs

Traditional production uses eggs separated from the connective tissue of the ovaries. The fish is harvested, and the roe is removed and processed under controlled conditions.

Ovulated eggs

Codex also allows ovulated eggs from aquacultured sturgeon. These eggs require appropriate treatment to remove the adhesive layer and harden the shell. Where hormones are used to induce ovulation, Codex says they should be approved by the competent authority.

Terms such as "no-kill", "stripped" or "surgically harvested" can describe different procedures. They should not be used as automatic claims about welfare, quality or environmental impact without product-specific evidence.

Stage 4. Separating and cleaning the roe

The eggs are separated from tissue and cleaned before salting. Processors aim to preserve the egg membrane and remove unwanted material.

Equipment, water treatment, timing and handling differ between facilities. There is no responsible basis for claiming that every premium batch must complete this stage within one universal number of minutes.

Stage 5. Grading the batch

Commercial grading can consider:

• Species and declared hybrid status.
• Egg size.
• Colour and visual uniformity.
• Firmness and membrane condition.
• Aroma and flavour.
• Salt balance.
• Presence of broken eggs or excess liquid.

These characteristics do not create one global grading scale. Terms such as "Royal", "Imperial", "Special Reserve" or "Grade 1" can be producer or retailer classifications unless a defined standard is stated.

The most useful practice is to explain what a grade means for the specific seller rather than presenting marketing language as a universal rule.

Stage 6. Salting

Codex states that caviar covered by CXS 291-2010 contains at least 3g and no more than 5g salt per 100g of finished product.

"Malossol" means "little salt". The term describes a lightly salted style but does not identify the species, farm, age or quality of the eggs.

The old version of this article gave shelf-life ranges based only on salt percentage. Those ranges have been removed. Shelf life depends on the validated production process, ingredients, packaging, microbiological controls and storage conditions.

Can caviar contain ingredients other than roe and salt?

Yes. Do not assume every product is salt-only.

Codex permits relevant acidity regulators, antioxidants and preservatives listed in its general food-additives standard. Specific legal permissions depend on the market. For example, consolidated EU rules list boric acid E284 and sodium tetraborate E285 for sturgeon eggs within stated limits.

Consumers should read the ingredient list for the actual product. Retailers should not make "no additives" claims without supplier documentation.

Sources:

• Codex standards catalogue, CXS 291-2010
• Current consolidated EU food-additives regulation

Stage 7. Packing

Codex allows suitable food-grade packaging, including internally coated metal tins and glass jars. Repacking from larger to smaller containers is permitted under controlled conditions that maintain quality and safety.

For the granular caviar covered by the standard, caviar from different sturgeon species or lots should not be mixed during repacking.

Packaging style alone does not prove freshness or quality. The label, ingredients, storage conditions and supply-chain documentation are more informative.

Stage 8. Temperature control

Codex gives different temperature ranges for stages of the supply chain:

Stage	Codex temperature range
Packaging, storage and retail	+2C to +4C
Wholesale storage and transport	0C to -4C

Codex also says freezing and frozen storage are not permitted unless deterioration of quality is avoided.

For the consumer, the practical rule is simpler: follow the storage temperature and use-by information on the product label. The UK Food Standards Agency advises that domestic refrigerators should be 5C or below and that chilled food should spend as little time as practical outside the refrigerator.

Source: Food Standards Agency guidance on chilling food safely.

Stage 9. CITES labelling and traceability

The CITES universal labelling system applies a non-reusable label to the primary container. For original processing, the code includes:

1. A standard species code.
2. A source code.
3. The ISO country-of-origin code.
4. The year of harvest.
5. The registered processing plant code.
6. The lot identification number.

For repackaged caviar, the system records the information required for the repackaging plant and lot or permit reference.

The label makes a tin traceable within the regulatory system. It does not by itself prove flavour quality or every sustainability claim.

Source: Government-hosted Reference Guide to the European Union Wildlife Trade Regulations, pages 195 to 197. The format comes from CITES Resolution Conf. 12.7.

Stage 10. Food-safety controls

Food businesses must operate controls appropriate to their process and jurisdiction. These can include documented hazard controls, hygiene procedures, temperature monitoring, traceability, sampling and corrective actions.

The old article said every batch is tested for named microorganisms and that any failure is destroyed. That may be true for a particular facility or specification, but it is not safe to present as a universal process without plant documentation.

When Beleaev describes controls for a named product, the statement should be based on current supplier specifications and the applicable food-safety documents.

What a buyer can verify

A consumer cannot inspect every production stage, but can check several useful signals:

• The species information.
• The CITES label.
• The source and country codes.
• The ingredient list.
• The use-by date.
• The storage instructions.
• The retailer's refrigerated-delivery process.
• Whether marketing claims are tied to a named standard or certificate.

Frequently asked questions

Is all caviar made exactly the same way?

No. Codex provides a product standard, but farms and processors can differ in species, husbandry, maturity assessment, egg route, permitted ingredients, grading and packaging.

Does caviar always require killing the sturgeon?

No. Codex recognises appropriately treated ovulated eggs from aquacultured sturgeon as well as non-ovulated eggs. The precise procedure and its effects should be assessed for the named producer.

Is every farmed product sustainable?

Farmed origin is a source category, not a complete sustainability assessment. A credible sustainability claim should define the environmental or welfare criteria and provide supporting evidence.

Does a CITES label guarantee quality?

It supports identification and traceability. It is not a sensory grade.

Why can two batches from the same species differ?

Egg maturity, farm conditions, feed, salt, handling, age of the product and temperature history can all influence the result.

For wider context, read the complete guide to caviar, review the source-led nutrition figures, or move from production to the plate with our practical caviar recipes.

Sources and correction policy

• Codex standards catalogue, CXS 291-2010
• Government-hosted Reference Guide to the European Union Wildlife Trade Regulations, pages 195 to 197, explaining the format from CITES Resolution Conf. 12.7
• FAO cultured species profile for Acipenser baerii
• Current consolidated EU food-additives regulation
• Food Standards Agency guidance on chilling food safely
• GOV.UK food labelling guidance

If you identify a factual error, contact Beleaev with the source and passage. Confirmed errors will be corrected and dated.

Explore the Beleaev caviar collection for product-specific ingredients, storage instructions and availability.