Anglesey Sea Salt (Halen Môn): How It Is Made, What It Contains and How to Use It

Anglesey sea salt comes with its own rulebook. It’s been a Protected Designation of Origin since 2014,¹ so a published specification fixes where and how it can be made and what it can contain, right down to its calcium. It’s a flaky white sea salt made from the water of the Menai Strait, the channel between the Isle of Anglesey and mainland Wales, and it’s sold under the producer’s name, Halen Môn. Most cooks use it as a finishing salt, for its soft, crisp flakes, which are still harvested by hand.

At a glance

Where it comes from

The Isle of Anglesey sits off the northwest coast of Wales. The 2021 census counted around 68,900 residents, down from just under 69,800 in 2011.³ The Menai Strait is the strip of water between it and the mainland.

The specification makes the case that the water itself is the point. It describes the strait as served by the Gulf Stream, with no big cities or heavy industry on its banks, and says a sandbank and a mussel bank naturally filter the seawater before it’s drawn in. It also notes that shellfish pull calcium out of the seawater during the growing season.²

How it is made

The specification lays out the method:²

1. Seawater is drawn from the Menai Strait after passing the sandbank and mussel bank, then run through sand, carbon and spun polypropylene filters.
2. It’s concentrated in a seawater vacuum evaporator and flows into a saturator tank.
3. In the crystallizing tanks, gas heaters above the brine concentrate it further at 50 to 65 °C for a maximum of 23 hours, and crystals form on the surface.
4. The flakes are harvested by hand, scooped out with a shovel, and rinsed by hand in concentrated brine.
5. The salt is dried in a low-temperature oven at 85 °C to under 4% moisture.

Rock salt or other sea salt can’t be added at any point.²

Flavor and texture

The specification credits the salt with a clean taste without the bitterness that too much calcium can cause, and caps calcium at 0.08 to 0.15%.² The flakes are flat and soft, with a light crunch between your teeth.

The specification also says the salt contains over 30 trace elements, and sets maximum levels for several of them:²

Those are ceilings set by the specification, not measured averages. See Health below for what health authorities say about the minerals in sea salt.

History

According to the specification, the first records of salt making on Anglesey go back to Roman times. Salt making on the island peaked in the early 18th century, then shut down in the 18th century because rock salt was being added to strengthen the brine, which was seen as adulteration. The remains of a salt works survive at Holyhead in the north of the island.² The specification doesn’t say where that rock salt came from. The often-repeated claim that it was Cheshire rock salt isn’t in any source we found.

The current salt works, Halen Môn, started at Brynsiencyn in 1997.² You’ll often read that production resumed in the 1970s. The specification doesn’t support that.

Protected status

The name “Anglesey Sea Salt / Halen Môn” was registered as a Protected Designation of Origin with the EU on 15 January 2014 and, after Brexit, under the UK scheme on 31 December 2020, in product class 2.6, salt.¹ The producer notes that the UK scheme protects the name in Great Britain and the EU scheme protects it in Northern Ireland and the EU.⁴

The specification describes an additive-free salt and doesn’t mention smoked or flavored versions.

How to use it

Anglesey sea salt is mostly a finishing salt. Crumble the flakes over steak, roast vegetables, salads, eggs, buttered bread or chocolate desserts just before serving, where the texture is part of the fun. The fine and ground grades work for everyday cooking. Flakes are bulkier than fine salt, so in baking, measure by weight or use the salt type the recipe names instead of swapping spoon for spoon. For the general principles, see cooking with sea salt.

Buying and storage

Look for the protected name “Anglesey Sea Salt / Halen Môn”; the specification is what defines it. Salt doesn’t spoil. Keep the flakes in a closed container somewhere dry so they stay crisp.

Health

Most sea salts are about 40% sodium by weight, like table salt. The American Heart Association says sea salt may carry trace minerals such as magnesium, potassium and calcium, but that total sodium intake is what matters most for heart health.⁵ FDA sets the Daily Value for sodium at less than 2,300 mg a day,⁶ and WHO recommends adults eat less than 2,000 mg of sodium a day.⁷ Anglesey sea salt counts toward those limits like any other salt.

The specification allows up to 1 mg/kg of iodine and no additives,² so this isn’t an iodized salt.

Related salts and comparisons

• Sea salt
• Maldon sea salt and fleur de sel vs. Maldon salt
• Fleur de sel
• Celtic sea salt
• Smoked sea salt
• Table salt vs. sea salt
• Himalayan salt vs. sea salt
• Sea salt substitutes
• Too much sea salt