Sea Salt, Coarse, 1 kg

Coarse sea salt from the European coast has two distinct roles in cosmetic making. In large amounts, it forms the base of bath salts and body scrubs, where its large crystals come into their own. In small amounts, it thickens shower gels, shampoos and other surfactant-based products. It is obtained by crystallisation from seawater followed by drying, with no additives.

It is supplied in both food grade and cosmetic grade. The same salt is therefore suitable for body recipes, foot salt soaks and the kitchen.

What it is suitable for

• Bath salts – the base of most recipes. The coarse crystals can be coloured, scented with essential or fragrance oils and combined with dried herbs. They dissolve gradually in the bath.
• Body scrubs – the large grains exfoliate dead skin cells more strongly than fine salt or sugar. They are especially suitable for feet, elbows and thicker body skin.
• Thickening surfactant-based products – at a usage rate of 0.5–2%, it increases the viscosity of shower gels, shampoos and liquid soaps based on anionic surfactants.
• Soaps and bath bombs – it is used to make salt soaps and as an addition to ordinary cold process soap. In bath bombs, it forms a dry ingredient alongside baking soda and citric acid.
• Deodorants and scalp scrubs – salt appears in deodorant recipes and in salt scrubs for the scalp, which are rinsed out after application.

Use in formulations

Salt belongs in the water phase. In surfactant-based products, it works well to prepare a concentrated solution in a small amount of water and add it to the finished surfactant mixture in portions, while stirring. Viscosity keeps rising for a short time after each addition until the salt has dissolved completely, so it is assessed only after a few minutes. Coarse crystals dissolve more slowly than fine salt. When the salt is poured directly into a thick gel, undissolved grains therefore remain at the bottom.

The processing temperature should not exceed 80 °C. Salt tolerates acidic, neutral and alkaline pH and can be combined with anionic, amphoteric and non-ionic surfactants. The thickening effect is most evident in systems with an anionic surfactant.

In bath salts and scrubs, the salt does not dissolve; it serves as a carrier for fragrance, colour and oils. Essential or fragrance oil is mixed in drop by drop so that it is distributed evenly. Water-soluble dyes are added in a very small amount of liquid so that the salt does not start to absorb moisture. If the oils from the bath salt are to disperse in the bath rather than float on the surface, a solubiliser, for example Polysorbate 80, is added to them.

In cold process soap, the salt is dissolved in distilled water before sodium hydroxide is added to it. In salt soaps, where it makes up a large share of the mass, the coarse grain can feel scratchy in the finished soap. For this purpose, a finer salt is therefore chosen, or coarse salt is crushed before use.

Good to know

Sodium chloride is an electrolyte. In gel products thickened with carbomer or other salt-sensitive polymers, viscosity drops markedly after it is added, and sometimes the gel breaks down completely. Some emulsifiers react in a similar way. In such recipes, salt is added only after verification in a small test batch, or not at all.

With salt scrubs, bear in mind that the coarse grain irritates open cuts and freshly shaved skin. For the face or sensitive areas, finely ground salt or sugar is more suitable. In an oil-based scrub, salt grains are heavier than the oil and settle at the bottom on standing, so the product is stirred before use.

The raw material is not classified as hazardous and does not require a safety data sheet. Ordinary hygiene in production is sufficient when working with it.

It should not be confused with Epsom salt. Epsom salt is magnesium sulfate, a different substance with a different composition and different behaviour in the bath. Coarse sea salt differs from fine sea salt only in grain size. Fine salt dissolves faster and is suitable for face scrubs, while coarse salt lasts longer in a bath mixture and looks more striking.

Frequently asked questions