When exported fresh, fruits and agricultural products typically have a short commercial shelf life. Consequently, if a reefer container's temperature rises by just a few degrees for a few hours, an entire export shipment belonging to a cooperative or enterprise can lose its value, face rejection, or be forced into destruction in the destination country.

Mr. Nguyen Van Dat (Ca Mau), owner of a seafood export enterprise trading with China, shared that his unit once encountered a situation where seafood—specifically marine fish—lost moisture and turned darker during prolonged preservation, drawing complaints from his partner.

Lost color means lost value

After investigating, he realized that the preservation stage had failed to meet the required freezing temperature threshold of below -18°C. Furthermore, techniques such as ice glazing and vacuum packaging must be applied to resolve this issue.

"With frozen seafood, even a minor discrepancy in the cold chain is enough to degrade color and freshness, thereby driving down commercial value significantly," Mr. Nguyen Van Dat said.

In Bac Ninh, Ms. Nguyen Thị Minh Thuy, Director of the Luc Ngan Xanh Cooperative, stated that whether lychees command a good price depends heavily on their external appearance.

The skin must be bright red, the skin spikes must remain plump, and the stems must be green. Without proper harvesting and preservation, the lychee skin will turn brown, lose moisture, and lose its crispness.

If grade 1 lychees meet standards from harvest through to preservation, the export price can fluctuate from 4–7 USD/kg to the Chinese market or 8–12 USD/kg to Japan and the EU. However, if the temperature fluctuates during container transit, this batch of lychees will certainly fail to reach foreign supermarket shelves.

According to logistics experts, exported agricultural products rarely spoil because of long distances, but usually due to heat. This means a long transit duration is not necessarily dangerous, but just a few hours of poorly controlled temperature will cause quality to degrade rapidly.

When many fruits experience temperature variances inside containers—especially when the temperature climbs slightly higher—premature ripening can occur right on the vessel. Conversely, if the temperature drops too low below the standard, many agricultural products will suffer chilling injuries and turn black.

Exercising control to eliminate risks

Notably, while many believe that colder temperatures preserve goods longer, Mr. Rocky Thach Nguyen—CEO of Smart Link Logistics—argued that each type of fruit has distinct preservation requirements, and a single temperature level cannot be applied universally.

When bananas are exported, keeping them below 12°C will trigger freezing injury. At this point, the banana peel turns black, and the fruit cannot ripen evenly. This is why through research and export practice, the preservation temperature during transport for this fruit needs to be consistently maintained at 12–14°C.

Meanwhile, fresh durian possesses a complex physiology with a short ripening cycle of about 5–7 days, thus requiring specialized temperature settings. To preserve fresh durian, reefer containers must be set to a temperature of 13–15°C, with a ventilation level of 15–20% to ensure the fruit does not suffer from lack of airflow. Disrupting the temperature for just 1–2 hours will degrade the fruit's quality, leading to price-squeezing or shipment rejection.

For frozen durian exported to China (including whole fruit, purée, or durian pulp), the core temperature control process must comply with international standards. Within this, during the rapid freezing process, the product must be frozen at a temperature of -35°C or lower for at least 1 hour.

The freezing process must ensure the core temperature reaches -18°C or lower. Throughout the entire preservation and transportation process, the core temperature must always be maintained at -18°C or below in accordance with the CAC/RCP 8-1976 standard.

Evidently, cold preservation depends on each specific product and the requirements of each market. For demanding markets like Japan, the EU, and others, partners do not evaluate an enterprise based on a single beautiful shipment; they judge them by their capacity to maintain stable quality over a long period.

Therefore, to preserve the quality of exported goods across multiple shipments, close attention must be paid to temperature control, transit times, and container preservation methods.

By executing each stage correctly, exporters will step-by-step eliminate risks. For export units, poor cold preservation of agricultural commodities leads to double losses.

Ms. Nguyen Thị Thu Lien, representing the Transparent Food Association, stated that an export unit had its bananas returned because it failed to ensure correct temperature standards.

More regrettably, the transport unit, upon seeing this situation, showed no goodwill to cooperate with the export producer to find a suitable support or compensation plan, triggering a financial crisis.

While for every 40ft container of exported bananas, documentation fees alone run into hundreds of millions of VND. When a shipment is rejected, the exporter not only loses all revenue from that batch but also has to bear the "round-trip" logistics costs or destruction fees in the destination country, calculated in USD.

Not to mention, that entity also faces additional fines for breach of contract from the importing side. These factors erode the finances and reputation of the importer, causing them to lose their advantage in the supply chain and distribution system.

Source: Vnbusines