Electrolyte Mineral Water Formula Sheet

Mineral waters, sometimes called electrolytes, originated from natural springs and volcanic mineral waters millennia ago. We still drink these waters today, just like Romans did thousands of years ago. However, we mostly drink them from bottles today under brand names like Perrier, Gerolsteiner, Apollinaris and Badoit water, though they are from the natural spring. One cool fact about the soda fountain was that they originally had a thriving business selling mineral waters and even had formulas to replicate natural spring water mineral content because shipping water across an ocean to America was prohibitively expensive.

Many of these recipes were published in several books, though the chemistry of replicating them properly can be difficult. The key issues are calcium and magnesium reacting with carbonates (and phosphates) to form insoluble calcium and magnesium carbonate, basically chalk. There are ways to work around this issue. One is to use carbonation to help dissolve the carbonates, but it needs to be done properly. The second option is to avoid forming calcium and magnesium carbonate by avoiding the mineral salts that react.

This is the key to formulating your own mineral and electrolyte waters. You can't mix different mineral salts together and expect them to stay the same; they, more often than not, react with one another to form different compounds. Creating different flavour profiles, as well as the aforementioned insolubility issues.

There is some great research on which mineral salts people prefer, and here are references to three on which I've based the mineral water formulation. Due to copyright restrictions I can't share the papers, but if you have questions about them, post a comment below.

Influence of minerals on the taste of bottled and tap water: A chemometric approach
Stefan Platikanov, Veronica Garcia, Ignacio Fonseca, Elena Rullan, Ricard Devesa, Roma Tauler (Water Research, 2012)

Predicting consumer preferences for mineral composition of bottled and tap water
Stefan Platikanova, Alejandra Hernández, Susana González, Jose Luis Cortina, Roma Tauler,
Ricard Devesa (Talanta, 2016)

Guidance for optimizing drinking water taste by adjusting mineralization as measured by total dissolved solids (TDS)
R. Devesa, A.M. Dietrich (Desalination, 2018)

Research Results

The key findings of these research papers are that people prefer mineral waters with calcium, magnesium, sulphate, and bicarbonate ions, as well as a higher pH (alkaline). Higher total dissolved solids (TDS) in the 200 to 800 mg/L range are preferred over distilled water or low TDS content. Some people preferred sodium chloride (table salt) ions. The ions that are less appealing are potassium and chloride, and if you've ever tried potassium chloride (no sodium salt substitute) straight, you'll understand why it is less likable, though it is fine in small amounts.

Calcium sulphate, like bicarbonate, is associated with the general pleasantness of water. For the included formulation, calcium sulphate works well because it does not easily react with sodium or potassium bicarbonate to form calcium carbonate.

Almost all other commonly available calcium salts will react with bicarbonate ions to form insoluble calcium carbonate, and you don't want that unless you can carbonate you mineral water to help dissolve it. I have tested many calcium salts with sodium bicarbonate and calcium sulphate is the best option.

Bicarbonate is the ion that increases pH, and the higher pH, in the 8 to 9.5 range, is often perceived as pleasant. Bicarbonate also neutralizes stomach acid, so some people gravitate toward these high-bicarbonate waters to settle their stomachs.

Three of the most popular commercially available mineral waters are in the 200 to 800 TDS (mg/L) range:

Evian - 300 mg/L
Perrier - 470 mg/L
San Pellegrino - 854 mg/L

Other mineral waters are higher in TDS and may appeal to you, so feel free to experiment with these levels to see what suits you. However, bicarbonate makes up most of the TDS content in these mineral waters, so using sodium and potassium bicarbonate is the best option.

Badoit - 1200 mg/L
Apollinaris - 1600 mg/L
Gerolsteiner - 2488 mg/L

 An important note is that most tap water already contains minerals, so if you plan on making your own water, you need to factor that in or use distilled water. I recommend tasting samples of individual minerals with distilled water to understand how different salts taste. I recommend tasting at about 400 mg/L. Note that there are differences, but they can be subtle, so if you don't notice much difference, you are not wrong.

Modern Mineral Salts

Most of the old formulations for mineral water typically comprised inorganic salts, like those mentioned above. Other salts can be used, like citrates, malates, glycinates and many others that aren't found in mineral springs but are still common in nature. For example, potassium citrate is just the citric acid salt of potassium. So, if you mixed potassium bicarbonate with citric acid, you'd get potassium citrate and carbon dioxide bubbles. Sodium acetate is just sodium bicarbonate and vinegar (acetic acid). These salts can provide different flavours, often a slightly sour flavour, and lower the pH more towards the mildly acidic. But they can be handy when dialling in a specific pH.

You can also find salts that are made from amino acids, like magnesium glycinate and sodium aspartate. These can provide some interesting flavours, specifically glycinate salts, which tend to taste slightly sweet and make your water pleasant and less harsh. I will eventually do a video on this topic as it is quite interesting. Still, for amino acid salts, the TDS used with mineral salts is different, so you could use 1000 mg/L to 2000 mg/L of magnesium glycinate in a formulation and only get 14 to 28 mg of elemental magnesium. But more on this in the future.

Notably, most calcium amino acid salts are still problematic and will react with bicarbonates to become insoluble.

Safety

Mineral salts are quite safe, though try to keep the levels for any one salt to less than 2000 mg/L. Certain magnesium salts, like magnesium citrate or chloride, are used as laxatives so keep the levels lower. Amino acid salts of magnesium don't have the same issue. Excess potassium can be an issue, though working with potassium salts below 500 mg/L should not cause any issues.

You should stick with calcium, magnesium, sodium and potassium salts, though others like zinc, lithium, iron and copper were common in mineral springs; they are used at ultra-low levels and don't really do anything for taste. Zinc might be the exception that I'll post about in the future.

Avoid nitrate, nitrite and sulphite salts as well as things like sodium and potassium hydroxide.

In old books on mineral water formulas, you may come across some formulas that are really high in salts. These were medicinal mineral waters and not meant to be used as table water. Some examples are Hathorn and Hunyadi waters. Most books will label them as medicinal.

Sourcing Mineral Salts

Finding mineral salts is quite easy. Here is a quick list of places to find salts:

Sodium Bicarbonate - grocery store, called baking soda (not baking powder)

Magnesium Sulphate - pharmacy, often used as a bath salt, though approved for internal use

Calcium Sulphate - gypsum, which is common at homebrew stores and is used to make tofu

Potassium Bicarbonate - found at health food stores or online and is a good source of potassium

Citrate and amino acid salts are easily found online. For many ingredients, my go-to source is Bulk Supplements, which ship to the US and Canada, possibly elsewhere.

Health food stores are a great place to buy salts, but only buy pure powders and don't use anything that has been put in a capsule as they often contain flow agents (helps get material into the capsule). Two of these are magnesium carbonate and silicon dioxide (basically really fine sand), and both are used because they don't absorb water, which keeps the powders from getting sticky. But this excellent property also makes them insoluble in water.

This is a big topic, so I will have more to say on it in the future. I plan to create formula sheets for some mineral waters, like Perrier, Badoit, and Apollinaris. Why ship water across an ocean when you can make it in your kitchen?

Questions? Post them below.

YouTube Video: https://youtu.be/rUS7qi6_xvQ