Container Load Math: Packing and Freight Planning for Freeze-Dried Lotus Seeds
A supply chain manager budgets a 20ft container the way they budget for heavy agricultural cargo, by weight, and the first freight invoice arrives higher than the model predicted. The error sits in the unit of measurement.
Freeze-dried lotus seeds fill a container long before they weigh one down: the vessel door closes on a stack of roughly 570 cartons that together carry about 4.560 kg of product, while the same container accepts up to 27 tons of denser cargo.
Planning this category requires counting cubic meters first and kilograms second. This article lays out the carton specification, the layer math for 20ft and 40HC units, the port options out of Vietnam, and the ordering rhythm that keeps production aligned with the shipping plan.
The Answer
A 20ft general purpose container holds about 570 cartons of freeze-dried lotus seed at the standard configuration of 8 kg net per carton, which totals roughly 4.560 kg net. A 40ft high cube holds about 720 cartons, or roughly 5.760 kg net.
The cargo is volume-limited, not weight-limited: freight moves by the space it occupies, and the carton is configured at 8 kg net with aluminum film bags to protect the fragile crisp kernel, not to fill the carton’s physical capacity of 32 to 41 kg.
Why the Carton Holds 8 kg, Not 41
The carton measures 60 × 39 × 39 cm, which gives 91.26 liters of internal volume. Freeze-dried foods bulk density depends on the pretreatment, and studies of freeze-dried grains place the density of porous dried structures in the range that translates, for a dense starchy kernel with a porous surface like lotus seed, to an estimated 0.35 to 0.45 g/cm³ of packed bulk density [1]. At those densities a 60 × 39 × 39 cm carton holds 32 to 41 kg physically.
Nobody packs 32 to 41 kg net into one carton for this product, and the reason is mechanical, not regulatory. Freeze-dried kernels are crisp and compress badly. A heavier carton crushes the bottom layers during stacking, and manual handling practice in fruit and vegetable loading caps cartons at roughly 10 kg gross for stack safety.
The standard configuration therefore pairs two inner PE aluminum bags of 4 kg each inside the five-ply carton: 8 kg net per carton at roughly 9 kg gross. The aluminum film locks moisture below the water activity spec at packing time, the subject of water activity below 0.3: the number that protects lotus seed shelf life, so the carton weight does not compete with product protection.
Buyers who want a denser fill per carton can discuss a 5 kg × 2 configuration at 10 kg net, but the 8 kg net carton remains the primary spec because kernel integrity travels better through the stacking cycle it produces.
The Container Layer Math
The load plan follows floor loading rules: cartons go directly on the floor or on pallets, and layer count comes from the door height, not the internal roof height, because the stack must clear the doors at both ends.
| Parameter | 20ft GP | 40ft HC |
|---|---|---|
| Internal floor | 11.90 × 2.35 m | 12.03 × 2.35 m |
| Door height | 2.28 m | 2.58 m |
| Carton footprint (0.60 × 0.39 m) | 19 × 6 = 114 cartons/layer | 20 × 6 = 120 cartons/layer |
| Layers (carton height 0.39 m clears the door) | 5 layers (1.95 m) | 6 layers (2.34 m) |
| Total cartons | 570 | 720 |
| Net product at 8 kg net/carton | ≈ 4.560 kg | ≈ 5.760 kg |
| Container weight capacity | 27 t (unused; only 17% binds) | 26 t (unused; only 22% binds) |
A six-layer stack in the 20ft would reach 2.34 m and fail the 2.28 m door. The 40ft high cube earns its extra layer precisely because its 2.58 m door clears six layers. The result is the defining number for order planning: one 20ft carries about 4.560 kg net, one 40HC about 5.760 kg net, and the difference in unit freight behavior between them belongs to the volumetric discussion below rather than to weight.
Volume-Limited Cargo: What It Changes About the Freight Model
The 20ft container accepts 27 tons, yet freezes at 4.560 kg of this product. Every freight rate applied to this lane therefore spreads across far fewer kilograms than a buyer used to heavy produce expects. The practical consequence runs through the whole buying plan.
Freight moves by volume, so the useful comparison between a 20ft and a 40HC on this cargo is the net kilograms per cubic meter, not the rate per container.
The production rhythm inherits the same geometry: a full 20ft represents about 25.000 to 30.000 kg of fresh lotus seed at the raw material end, the fresh-to-dry ratio behind that number stands documented in fresh-to-freeze-dried ratio: how much fresh lotus seed makes one kilo, which is why the harvest window of July to September sets the order calendar rather than the order calendar setting the harvest.
For buyers testing the channel before committing to container volume, LCL consolidation from Cát Lái port or air freight from Tan Son Nhat airport both work with the same 8 kg cartons, and the carton spec above transfers directly into those modes without repacking.
Port Options and Trade Terms
Shipments leave through Cát Lái port, the main container port serving the Ho Chi Minh City industrial corridor, for sea freight, or through Tan Son Nhat airport for air freight on LCL-scale volumes.
Trade terms follow the buyer’s control preference: FOB hands freight booking to the buyer’s forwarder, CIF places it with the supplier, and DDP delivers to door.
Payment runs T/T with 40 percent at order and 60 percent against shipping documents, or L/C at sight, and the documentation set that accompanies every shipment, from phytosanitary certificate to certificate of origin, is mapped in importing lotus seeds from Vietnam: HS code and documentation checklist.
Storage Behavior Inside the Container
The product’s protection travels with the cargo. Cartons ship floor-loaded or on dry pallets clear of wet floors, and the aluminum film barrier that holds water activity at packing stays intact through transit as long as the seal survives. Buyers with containers sitting at destination yards through humid months should keep the same rule that applies at warehouse: the spec in the freeze-dried lotus seeds specification assumes unbroken aluminum seals, and a breached seal converts the load into an exposure question rather than a shelf life question.
FAQ
How much freeze-dried lotus seed fits a 20ft container? About 570 cartons at 8 kg net each, or roughly 4.560 kg net.
How much fits a 40ft high cube? About 720 cartons, or roughly 5.760 kg net.
Why not pack the carton to its physical capacity of 32 to 41 kg? Freeze-dried kernels are crisp and crush under compression; the 8 kg net configuration protects kernel integrity and matches manual handling limits of roughly 10 kg gross.
Is this cargo weight-limited or volume-limited? Volume-limited. The container reaches its space ceiling at under 6.000 kg, far below its 26 to 27 ton weight capacity.
Can I ship less than a container? Yes. The same 8 kg cartons work for LCL consolidation from Cát Lái port or air freight from Tan Son Nhat airport.
How should cartons be stored inside the container? Floor-loaded or on dry pallets, clear of wet floors, with seals intact for the water activity spec to hold through transit.
How does the harvest season affect the load plan? A full 20ft requires about 25.000 to 30.000 kg of fresh kernel input, and fresh kernel supply concentrates in the July to September harvest window, so peak season orders should enter the production queue early.
Send Us Your Monthly Sales Plan, Not Just a Container Number
Send the monthly sell-through estimate for the SKU, the target port, and the trade term, and the team returns the load plan in cartons, the production slot in the 20 to 30 day queue, and the harvest window the plan lands in.
References
- Nowak, D. and Lewicki, P.P., Foods (2020), The Freeze-Drying of Foods: The Characteristic of the Process Course, the Effect of Its Parameters on the Dried Product Quality (bulk density của sản phẩm thăng hoa theo tiền xử lý, 590+ trích dẫn ): https://www.mdpi.com/2304-8158/9/11/1587
- Sky Queen Logistics (2024 ), Hướng dẫn thủ tục xuất khẩu hạt sen khô (thuế xuất 0%, cảng Cát Lái, hồ sơ phytosanitary ): https://skyqueen.vn/thu-tuc-xuat-khau-hat-sen-kho/
- VinaSources (2026 ), Guide to Sourcing Vietnamese Lotus Seeds (vùng trồng Đồng Tháp-Huế-Hưng Yên, mùa vụ tháng 7-9, thị trường nhập chính ): https://vinasources.com/blog/vietnam-lotus-seeds/
- USDA FoodData Central, Dried lotus seeds, FDC ID 170149 (thành phần per 100 g thành phẩm ): https://fdc.nal.usda.gov/food-details/170149/nutrients
- Specialty Produce, Lotus Seeds description (kích thước hạt và dạng sấy ): https://specialtyproduce.com/
