Zalmboerderij Maashorst

KOOK BEWUST

Zalmboerderij Maashorst

In Uden, Brabant, on the site of a former pig farm, Rob Dortmans is realising his vision of the future of salmon farming. Instead of barns full of livestock, Atlantic salmon now swim here in chilled freshwater tanks on land. Zalmboerderij Maashorst is the first salmon farm in the world to raise salmon from egg to adult fish in a fully closed freshwater system. A local and sustainable alternative to conventional farmed Atlantic salmon from Norway.

The farm has been designed as an open place for meeting and education. Alongside the farm, there will be a processing area, dry-ageing cabinets, a shop and an education centre. The aim: to show that salmon production can be done differently – transparently, under control and with minimal impact on the surroundings.

Sfeerbeeld Zalmboerderij Maashorst bassin

What makes Zalmboerderij Maashorst different?

The salmon is produced entirely at one location: from egg to end product. The first growth stage takes place in covered tanks with maximum control over water quality and light. After about a year, at a weight of around 100 grams, the fish move to insulated outdoor tanks where they grow on to their target weight.

By working cleverly with growth differences within the groups, the farm can deliver fresh salmon every week with just two batches of eggs a year. The entire chain – from rearing, slaughter and processing to sale – takes place on site. This eliminates almost all the transport kilometres that are usual for imported salmon.

Closed freshwater system

Zalmboerderij Maashorst works with a fully closed recirculating aquaculture system (RAS) in fresh water. The water is continuously biologically filtered and reused.

Water is purified by an ecosystem of beneficial bacteria.
Residues are reused in regional food production.
Purified water is returned to nature.

This way of working keeps the surroundings completely separate from production and keeps water use to a minimum.

Sfeerbeeld Zalmboerderij Maashorst vissen

How Zalmboerderij Maashorst works

1. Space and calm The stocking density is about half of what is usual in other land-based systems. Fewer fish per cubic metre of water means more swimming space, less stress and more stable water conditions. All outdoor tanks are connected by a swimming channel. When the fish need to move, a grate is opened and the salmon swim to the next tank on their own. No landing nets or fish pumps are needed.

2. Antibiotic-free and nature-inclusive Thanks to optimal water quality, low stress and a robust bacterial ecosystem, the salmon can be farmed completely without antibiotics or chemicals. The focus is on prevention through good housing and biological balance, rather than correction afterwards.

3. Low CO₂ impact
Because the entire chain is local, transport kilometres are greatly reduced. According to the farm, this results in a CO₂ reduction of 50% to 75% compared with, for example, imported Norwegian salmon.

Sfeerbeeld Zalmboerderij Maashorst dry-aged zalm

Dry-aged salmon

In addition to gutted whole salmon, Zalmboerderij Maashorst also offers gutted dry-aged whole salmon. After low-stress slaughter, the salmon is not kept on ice, but stored dry in a chilled ageing room. From that moment on, no more moisture is added. So the fish does not lie on ice in its own liquid for days, as happens in many conventional chains.

As standard, the salmon is aged for around 7–8 days, developing a layered flavour profile and an improved texture.

Ikejime method

Zalmboerderij Maashorst uses the traditional Japanese Ikejime method at slaughter. The fish is stunned in the water, then killed with a precise movement and bled immediately. This method limits stress and helps preserve texture, optimal water-holding capacity, a pure flavour profile and improved shelf life. This makes the salmon suitable for high-end gastronomic applications.

Nose-to-tail approach

Beyond fillets, there is a strong focus on using the whole fish. The other parts are developed into products such as stocks, soups, sausages and burgers. Salmon fat is also used as a high-quality raw material. This minimises waste and makes optimal use of the value of the fish.