Flexitank vs Isotank: How to Ship Bulk Olive Oil

For the vast majority of bulk olive oil buyers, the flexitank is the default choice: 21 to 23 metric tons per 20-ft container, a brand-new single-use bladder and, in most configurations, the lowest landed cost per ton. The isotank earns its place in specific scenarios: recurring flows on the same lane, high-value sensitive lots, or a discharge site already equipped for tank containers. Drums and IBCs, meanwhile, remain the solution for fractional volumes. Here is how to decide, line item by line item.

The flexitank: the standard for food-grade bulk

A flexitank is a multilayer food-grade polyethylene bladder installed inside a standard 20-ft dry container. It is built for a single voyage: delivered new, fitted before loading, destroyed after discharge.

On capacity, the usual range is 21 to 23 tons of oil per container. At a density of roughly 0.916 kg/L, 22 tons works out to about 24,000 liters. That weight-to-volume ratio is one of the format's key strengths: you load an ordinary dry container, available everywhere, without tying up specialized equipment.

What the flexitank does very well

• Hygiene by design: the bladder is new and sealed. No cleaning to verify, no risk of cross-contamination from a previous cargo.
• Cost per ton: a standard container, no tank repositioning, no cleaning service. On most lanes, it is the most economical option above roughly twenty tons.
• Documentary simplicity: a food-contact compliance certificate for the bladder plus the seal are enough, where a tank container requires a full cleaning file.

Its real limitations

• Discharge has to be organized: you need a pump and a buffer tank able to take the entire lot. A flexitank does not allow split deliveries.
• Single use: the bladder is a consumable to be factored into cost, along with handling its disposal after emptying.
• Sensitivity to handling: loading and bracing must be carried out by a trained operator, and some shipping lines require approved bladders and certified installers.

The isotank: the reusable stainless steel tank

An isotank is a stainless steel tank mounted in a 20-ft ISO frame. Typical payload for olive oil: about 24 tons. It is multimodal equipment (sea, road, rail) and reusable, operated by specialized tank operators.

It makes sense in three situations: regular rotations between the same points, where the operator can optimize tank positioning; high-value lots for which the buyer wants a rigid stainless steel vessel end to end; and winter discharges in northern Europe, because olive oil solidifies at low temperatures and some tanks allow gentle reheating before emptying.

In return, the tank must be cleaned and must prove it: a cleaning certificate (ECD type) and traceability of previous cargoes are non-negotiable, since olive oil is only loaded after compatible food-grade products. Cost depends heavily on tank availability on the lane in question: on an unbalanced route, repositioning quickly drives up the cost per ton shipped.

Drums and IBCs: the second line

Steel or plastic drums and IBCs of about 1,000 liters keep their place for volumes below a full container load, multi-SKU orders and customers without discharge infrastructure. A 1,000-liter IBC holds about 916 kg of oil: the landed cost calculation must factor in the weight and price of the packaging, unit handling and the payload lost inside the container. Cost per ton is structurally the highest of the three formats, but it is also the only one that allows fractional distribution without any equipment.

Comparison table

Criterion	Flexitank	Isotank	Drums / IBCs
Payload (20-ft basis)	21 to 23 t	~24 t	Reduced by packaging
Hygiene	New single-use bladder	Certified cleaning mandatory	New or reconditioned packaging
Cleaning file	None	Certificate + previous cargoes	Depends on packaging
Discharge	Pump + buffer tank	Standard fittings, reheating possible	Unit handling
Split deliveries	No	Limited	Yes
Cost per ton	Generally the lowest	Varies by lane	The highest

Which format for which buyer profile

• Bottler or blender equipped with tanks: flexitank, unless a highly recurring flow justifies an isotank contract.
• Industrial buyer with procurement planned across the season: isotanks in rotation, negotiated with a tank operator, especially if the site already receives food-grade liquids in tank containers.
• Distributor or packer without tank storage: IBCs and drums, or private-label packaged product directly — see our bulk offer, which covers both approaches.

Common mistakes

1. Comparing freight per container instead of landed cost per ton. Attractive tank freight can hide a cleaning charge, repositioning and a different payload. Bring everything back to cost per delivered ton — our calculators are built for exactly that.
2. Neglecting discharge planning. An unavailable pump, an undersized buffer tank, a missed slot: demurrage costs more than the freight spread between two options.
3. Accepting a tank without a complete cleaning file. Without a certificate and the list of previous cargoes, the quality risk is unacceptable for a food product.
4. Forgetting temperature. Olive oil partially solidifies in the cold: a mid-winter continental discharge needs preparation (reheating, lead times).
5. Locking in logistics before quality. The container never rescues a mediocre lot: demand the certificate of analysis before committing, as explained in our guide to reading a COA.

Bottom line

Flexitank for cost and simplicity on a full shipment, isotank for recurring flows and demanding discharges, drums and IBCs for fractional volumes: the right choice follows from your volumes, your equipment and the regularity of your needs. Virginia ships Tunisian olive oil in all four formats, with a COA on every lot. Tell us about your flow and your receiving site: request a quote and we will price the relevant options, in landed cost per ton.