The latest research results from scientists at the Biochemistry Department, Nha Trang Oceanography Institute have confirmed: “Even in fish sauce made from pufferfish, deadly toxins still exist!“
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| Research on pufferfish fish sauce in the laboratory (Photo: Labor) |
Dr. Dao Viet Ha – the head of the project – stated: “Within the framework of the research project of the Vietnam Academy of Science and Technology, we used the orange-spotted pufferfish – a species that is often harvested in large quantities and widely consumed – as the research subject. The experiments were conducted over a year, applying the local fish sauce production methods and determining the toxicity levels at various time points.”
The orange-spotted pufferfish, commonly known as striped pufferfish or flower pufferfish, has the scientific name Torquigener pallimaculatus. The toxins are concentrated in the eggs, liver, internal organs, and skin, with 100 grams of eggs or skin capable of killing 60-70 people.
The research results indicate that the toxicity tends to decrease over time: after 12 months, the toxicity levels reduced by approximately 86.43% – 93.93% compared to the initial toxicity.
Dr. Dao Viet Ha and colleagues analyzed: “It is important to note that after 12 months, under the specific conditions of the fish sauce production process (very high salinity, acidic or neutral pH), a certain amount of toxins still remains in the product (6.07% – 13.57%).”
In reality, only 3-4 months after processing begins, fish sauce products are already available on the market. According to data collected from this study, the third month is when the toxicity still exists at approximately 49.44% – 37.47% of the original level. Typically, the toxicity of the orange-spotted pufferfish during spawning season can reach up to 5,000 MU/g. Therefore, after 3 months, at least around 1,870 MU/g of toxicity remains. A normal person consuming just 25 – 50 ml of this type of fish sauce could suffer poisoning that may lead to death.”
On February 11, reporters from Labor newspaper discussed this information with some fishermen in Con village, Xuong Huan Ward, Nha Trang City. It was noted that besides the orange-spotted pufferfish, fishermen also use other pufferfish species as ingredients (with a ratio of 1 ton of fish yielding 300 liters of fish sauce) and the locals believe that the toxins will be completely eliminated after a few months of fermentation.
Dr. Dao Viet Ha further explained: “When using pufferfish mixed with other fish species, the toxicity in the fish sauce product may not reach the high values observed in this experiment, but that does not guarantee food safety. A seafood product is only confirmed as safe when no traces of pufferfish toxins are found. It should also be noted that the toxicity of pufferfish within the same species can vary significantly; meanwhile, there is no accurate data on this issue in Vietnam; therefore, it is impossible to fully assess the toxicity of pufferfish when used in large quantities to make fish sauce.”
