Pink, black, blue and other coloured salts: how good are they nutrition-wise?

Do these gourmet coloured salts* have more value in a nutritional or culinary way, or both?

Harvested and mined from lava flows, volcanoes, lakes, underground aquifers and oceans from exotic locations such as Peru, Persia, Bolivia and Pakistan (Himalayas) along with more local destinations close to the Grampians in Victoria and down from the Murray River, coloured salt crystals look like precious gemstones. The colours are surprising.

But not so the taste. Unless your palate is exceptionally refined, I suspect you will be hard-pressed to taste the difference between different coloured salts if you were blindfolded.

They taste salty, as salty as white salt crystals, because sodium chloride is the dominant component in both coloured and white salt crystals. Coloured salts also contain very very tiny amounts of other natural impurities or contaminants such as minerals, heavy metals, trace elements, carotenoids. The amounts present are very tiny but they are enough to taint the colour of pure salt.

Transparent white salt is a more pure and contains fewer impurities.

According to a report from Spexcertiprep (an analytical laboratory), grey and black salts  (in particular Indian Kala Namak) tend to have higher levels of toxic elements: lead, arsenic, mercury or cadmium. This undesirable contamination is understandable when coupled with information from the Food and Agriculture Organization of the United Nations (FAO) notes on salt cropping in Bangladesh:"The quality of crude salt varies depending on the substrate used for collecting deposits of sediments in the salt bed. When the substrate is soil, the salt produced is black and of inferior quality because it contains a substantial proportion of mud (10 to 20 percent) and other impurities." Clearly, attempts are made to remove mud and other impurities before the black salt is fit for human consumption. Black Cyprus salt contains fewer impurities than Indian black mineral salt.

The basic nutrient profile of a few coloured salts is shown in the linked chart and table (pdf downloadable file)..

You quickly see how much sodium chloride is present and how little there is of anything else. I’ve compared the coloured salts with regular table salt and iodised salt.

To put the values in perspective, I’ve added chili powder, black pepper, instant coffee and dried seaweed to the table.

You get better nutritional value from a teaspoon of instant coffee than a teaspoon of coloured salt. A sprinkling of crushed dried seaweed would add more nutrients, a distinct flavour and less sodium than any salt.

Coloured salts in the salt grinder or as a garnish glisten gorgeously.

I can’t detect a big difference in taste but I don’t claim to have a gourmet’s fine tastebuds. I am very salt sensitive because I don’t use a lot of salt. The coloured salts I have tried so far do nothing for my food except add saltiness. I haven’t tried any salts with a higher sulphur content, which if sufficient may subtly deliver a pungent aroma and add to the taste.

If you have a more sophisticated palate you might be able to detect subtle differences. These subtle differences in ingredient quality and flavour profiles do influence the final taste of a fine meal.

Bottom line?

The salts offer culinary value and appeal rather than nutritional benefit. If you want to cut down on sodium salt, ditch both the coloured salts and ordinary white salt. The colours do not transform salt into a health food.

Importantly, if you know someone who is breastfeeding or pregnant, an iodised salt (has added iodine) is a wiser nutritional choice, for when salt is added. Iodine deficiency will cause baby to have developmental problems and a reduced IQ.

None of the coloured salts I reviewed are iodised.

According to Food Standards Australia, Victoria, New South Wales and Tasmania are areas of mild iodine deficiency, and iodine status in South Australia is borderline. Mild iodine deficiency is associated with a reduced IQ. In severe deficiency, cretinism is seen. These are preventable.

*When I refer to salt, I mean sodium chloride salt. Information is sourced directly from manufacturers and official Australian and international food composition tables, and analytical laboratories.