the technology that allows tropical prawns to be raised in the middle of Castilla

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When we speak of “pata negra”, we speak of a truly unique concatenation of elements: they are not only pure-bred Iberian pigs, but they are fed in the dehesas based on acorns and pastures. I mean, it’s not just biology, it’s ecology. They can’t be recreated because our climate technology doesn’t go that far. for now

And I say “for now” because although it is true for land animals, when we talk about fish things change. In recent years, our technology to recreate aquatic ecosystems has become so advanced that it is possible that soon we will stop talking about the sturgeon from the Caspian Sea, the red prawns from Garrucha or the shrimp from Motril: all the fish we want can be raised in pools with perfectly controlled ecosystems. And no, It is not the plot of a science fiction series.

Sustainable fish is bad for the environment

A fishing ground in the middle of the plateau. In Medina del Campo, in the middle of a dry moorland more than 300 kilometers from the nearest sea, 24 heated pools they raise 50 tons of tropical shrimp each year. The tanks of ‘Noray SeaFood‘ (previously known as ‘Gamba Natural’) have capacities of between 150 and 220 cubic meters. There, at 28ºC, in the dark and with a mixture of tap water and salt from the Red Sea, they grow two million prawns. How is it possible?

RAS technology. The Aquaculture Recirculation Systems (RAS) are technologies that allow fish to be farmed in tanks rather than in open-air ponds. They are very popular systems because, by allowing advanced control of the rearing environment, they favor the rearing of fish in high densities.

Infographic Ras Derwent Es 768x768

However, they require enormous accuracy: any failure in the rearing environment can kill the entire production. “The filters in the recirculation systems clean the water and recycle it, sending it back to the culture tanks.” That is, new water is only added to the tanks to compensate for water loss “from splashing, evaporation, and to replace that used to dispose of waste materials.”

Where do prawns come from? Although the installations are expensive (the initial investment was more than 12 million dollars), the most sensitive part when starting the work is to find authorized larvae suppliers. European legislation is very strict and, finally, those from Medina del Campo come from larvae bought in Isla Morada (in Florida, USA).

The rest of the process involves artificial insemination techniques, to fertilize an average of 100,000 eggs in each clutch. After 15 days, it goes to the tanks where controlled ecosystems are recreated with 4% oxygen and a mixture of feed (flour, fish oil, etc.) and amino acids to ensure that the larvae reach their commercial size between the third and the fourth month of life.

a voracious market. Spain consumes 170,000 tons of shrimp each year. 95% is frozen and comes from countries such as China, Vietnam, Morocco, Colombia, Ecuador or Thailand at prices that range between 8 and 10 euros per kilo of retail price. Finding fresh shrimp is a much more complicated task and, therefore, its price per kilo can reach 45 euros.

However, this does not seem like an obstacle for a hungry European market. The company, right now, is allocating 70 percent of its production to Austria and Germany; and they already plan to double the size of their facilities. It is a good example, everything seems to indicate that RAS farms are going to mark the future of aquaculture.

Image | Alfonso Benayas

When we speak of “pata negra”, we speak of a truly unique concatenation of elements: they are not only pure-bred…

When we speak of “pata negra”, we speak of a truly unique concatenation of elements: they are not only pure-bred…

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