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Mussels Chez Léon

The reputation of the CHEZ LEON restaurant is essentially based on its concept of Mussels and Chips.
This mollusc is therefore at the very centre of the restaurant’s life and the quality of supply is consequently of utmost importance.


There is hardly any sea where mussels cannot develop.
Mussel farming is practised throughout the world. However, there are several species of this mollusc, and not all have the same taste and culinary qualities.
Delicious to eat, the mussel is prized for its nutritional qualities – protein, mineral salts, and very low fat content.
The nutritional value of 100 g of mussel meat is as follows:
– Energy: 57 calories = 242 Joules
– Albumin: 10 g
– Carbohydrates: 2 g
– Fat: 1 g
– Sodium: 300 mg
– Phosphorus: 250 mg
– Iron: 6 mg
– Vitamin C: 2 mg
– Vitamin B2: 0.17 mg
– Vitamin Bi: 0.15 mg
– Vitamin A: 0.05 mg

Around one tonne of mussels is consumed every day at CHEZ LEON in Brussels, or 360 tonnes per year.
The figures speaks volume about the demand for the product, especially of such impeccable quality as those served in CHEZ LEON.


For gastronomic as well as geographic reasons, the CHEZ LEON RESTAURANT is usually supplied from the Netherlands, a country known for the quality of the Zealand Mussel, a particularly tasty, large-sized mollusc. This provenance and this quality are the only ones accepted CHEZ LEON during the opening season, i.e. mid-July to Easter.
More specifically, a break is imposed by biological criteria, in particular the reproduction period of this mollusc, from Easter until mid-July.
Outside the harvesting season for the Zealand mollusc, the CHEZ LEON RESTAURANT is supplied from a country nearby, Denmark or England, which are also known for their production of mussels, whose quality nonetheless cannot equal that of Zealand. .

    While the Eastern Scheldt and the Zealand sea are the ideal environment for mussel farming (more on this point later), the ideal environment for mussel spawning is the WADDENZEE. Reaching a size of 5 to 6 cm, the mussels are cleaned from all supports and waste to be matured and have the sand removed from them in special basins.
    Once ready for sale, they are checked by the veterinary services and are issued a certificate which must displayed on the bags sold.
    But let’s take a closer look at the life of the Zealand mussel.


It is in this inlet, protected by West Friesland and fed by many streams that turn it into a low salinity environment, that mussel farmers come to collect the spat and cultivate it in the Eastern Scheldt. Thousands of larvae, smaller than 1 cm, are swimming on the coast and in the inlets. Spat collection is authorised only during a few weeks a year, in May and June, i.e. about a month after the mussel reproduction period, and is done by dredging the mussel beds. As the spat is still more or less floating in clusters and not yet fixed, the movement of the sea currents is decisive for detecting the location of the baby mussels. The skill of the mussel farmers is gauged by their ability to find the spat areas rapidly.


The combined action over several thousand years of the seaweeds and sand brought by the sea, together with the mud brought by the rivers that flow into it has led to the creation of embankments and the formation of lagoons filled with fresh water from the rivers.
Owing to storms and periods of rising waters, these embankments have not always been in the same places, but they have always existed, making this area a region very rich in peat, at times running several metres deep.
Man tried to settle in this region from the beginning of the 8th century, where in spite of the lowlands situated below sea level, these natural dykes provided protection from flooding. They were artificially reinforced by the construction of additional hillocks and dykes, although the fury of the sea often reclaimed what man had built with such toil.
The floods that disturbed life in this part of the world can be pinpointed: There were the disasters of 1014 and 1134, but above all the terrible flooding of Saint Felix in 1530, in which the entire town of REIMERSWAAL and its surroundings disappeared. This region, which is located to the east of VERSEKE, is today called the drowned land of  ZUIT – BEVELAND.
Stabilised since the 17th century, this delta thus consists of thick layers of fossilised peat and fine layers of silty peat that make it particularly suitable for mussel farming, but also for shellfish farming in general. Furthermore, the waters of the Eastern Scheldt, especially its East Basin, have a high temperature for the region, which is otherwise found only in the waters of southern Europe.
This phenomenon is due to the considerable warming of the immense peat bogs at low tide, which then transfer this heat to the water at high tide.
Owing to the natural cut of this estuary, the low tide of the Eastern Scheldt lasts an hour longer than that of the Western Scheldt. It thus pushes away the dirtier waters from the Western part and prevents them from penetrating in this inlet.
When this part of the coast was built, it was agreed that no sewer network would pollute this environment. Finally, strong South-to-North sea currents divert the waters of the Rhine to the North and prevent them from polluting the mouth of the Scheldt.
The combination of these three phenomena make the Eastern Scheldt, and its extension, the sea of Zealand, an ecologically very clean environment and therefore particularly suited for shellfish and mussel farming.


The inhabitants of this delta, so rich in fish and game, used to survive from hunting and fishing in times gone by.
Of course, they also fished for mussels on occasion, but for their own consumption and that of the surrounding villages.
Some fishermen soon discovered that they could transplant these molluscs from their region of origin to more protected areas and that not only they became bigger, but their taste also improved. This is how mussel farming originated.
In the Zealand region, for instance in TIIOLEN, PHILIPPINE, YERSEKE and ZIERIKSEE, this is how profession of mussel farmer and shipper came into being.
Until 1825, mussel fishing was unregulated.
The inhabitants of the regions around Zealand waters fished in the natural basins, but did not have facilities to protect and farm the mussels they had collected. This situation created a lot of difficulties between the fishermen in Zealand waters, but also and especially with fishermen who came from other regions.
At certain times, this lack of regulation led to an overexploitation of the areas and a sharp decline in the quality of this mollusc.
That is why, in 1825, a Royal Decree entrusted the administrative authorities with the management of this fishery on the Scheldt and the rivers of Zealand.
The administrative authorities determined the period for collecting the spat, and the division of this area into basins, and it proceeded to attribute these plots by a lottery system, and adopted measures concerning the period during which adult mussels could be harvested, the minimum size for this mollusc when sold, and the mandatory health certification.
This management of mussel farming has been continued through to the present day.
The city of PHILIPPINE had long been the commercial centre of the region, a role taken over in the beginning of the 20th century by YERSEKE.



When the spat is collected in the WADDENSEE, “the baby mussels” do not exceed a centimetre in size. The spat floats at that time massed together in clusters.
Deposited in thick layers in the basins of this warm and ecologically-protected environment of the Eastern Scheldt, it will develop rapidly and soon. The mussels become heavier than the water and fall to the bottom.
The byssal threads are then secreted and the small mussels get attached to any objects they find at the bottom of the sea.
They use their base to move some more until they find the place that suits them best. Once fixed, they scarcely move at all, unless survival instinct kicks in if the environment should become dangerous:  silting or sanding up, pollution, etc.
Mussels feed essentially on phytoplankton but also on animal plankton which they capture by filtering the sea water.
This plankton, which results from the development of many animal and plant species in the mud, sand, and peat of this part of the Scheldt, is stirred up by the sea currents and enables the mussel to find abundant food, despite being sedentary.
Mussels will stay in these nurseries until they are 4 to 5 cm in size, forming a substantial group on the bottom of the sea.


After this initial phase, the mussels are collected to be transported onto other plots that are richer in phytoplankton.
There, they will be able to reach their commercial size of about 6 cm.
These plots are constantly cleaned, maintained and inspected for the quality of the food.
They must above all be protected against the natural enemy of the mussel: the STARFISH. Starfish are very fond of mussels which they crush with their powerful arms before ingesting them. Some storms and sea currents at times bring impressive quantities of starfish that cause serious damage.
When the mussels have reached a sufficient size to be sold, they are sold at the YERSEKE mussel farming commercial centre.
That is where the mussel market is held.


To be admitted for sale, the mussel farmers must first pass an initial quality control inspection of their mussels.
Once the content of a vessel’s hold has been determined, a 2.5 kilo sample is examined by officials from the inter-professional seafood committee which supervises the mussel market.
This examination is conducted to determine: the waste percentage: empty shells, barnacles (a type of small shellfish), crabs, starfish, seaweed, etc… the size of the shell, the number of mussels in the sample, the net weight in cooked mussel meat, the results of this examination are posted on a large electronic board in the hall where the mussel market is held.
Fresh or tinned mussel traders use the same electronic board to preorder the cargo presented.
The name of the highest bidder and the price he/she offers are then displayed on the board.


As soon as they are sold at YERSEKE, the mussels are taken and carefully sown in the protected beds of wholesalers, still in the Eastern Scheldt. These overflow beds as they are known are located to the east of YERSEKE, in the immediate vicinity of the
dispatching facilities, in places with the oldest, most fossilised and least silted peat. The mussels will be revitalised and cleaned of sand in this resistant and very flat ground crossed by countless currents. The number of overflow beds is strictly limited.
The water in the overflow beds is clear, rising up to 3 metres during high tide, and cleared entirely at low tide.
The mussels are also very well protected against strong winds and high waves. The mussels are deposited there during high tide and are spread manually during low tide. This is very labour intensive, but indispensable to guarantee a quality product without sand.
These immense reservoirs can contain 10,000 tonnes of mussels over an area of 250 hectares. The quality of the water is sampled periodically for testing purposes, as the wholesaler is required to obtain a health certificate for the sale.

3.5 SALE

The mussels may still swallow sand during the last collection. They will thus be subjected to one last growout in special basins equipped with pumps and filters that provide a constant supply of clean and fresh seawater. They are then sorted and trimmed in preparation for shipment.
Machines are used to remove mussels that are too small, empty shells, seaweed and above all the byssal threads.
The latter operation is carried out with two rollers turning in reverse.
Laid out on a conveyor belt, they are inspected one last time before they are put in 15, 25 or 30 kg bags.
Very high consumer demand over many years has led to packaging in 1, 2 or 3 kg bags. All these mussels are in fact packaged so that they are ready to cook.
The YERSEKE plants have a packaging and shipping capacity of 30 tonnes/hour and process 100,000 tonnes per year.
This capacity puts the Netherlands among the very top mussel producers in the world.
Although consumption in the Netherlands is increasing constantly, the majority of shipments are for export, with Belgium and France being the biggest customers.
These shipments are dispatched by refrigerated trucks.
A considerable portion of these molluscs is nonetheless processed into tins, the best known of which are:   – mussels with vinegar  – mussels Niçoise style  – mussels with garlic butter
An increasingly larger quantity is now shelled and then deep frozen, making it possible to enjoy Zealand mussels year round.


Rudy Vanlancker has always been extremely keen on the notion of team spirit, this comes from the pride of being part of a company present for more than a century in the Belgian capital. He organises a convention every year for all the franchisees and direct employees of the Group.

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