My two cents on salt

Different types of salt

Fancy salts are currently in vogue. You better spend your money on a salt like fleur de sel, or you can impossibly cook a good meal. At least this is what you can read almost everyhwere. But is it really true? Does it make any difference whether you use fleur de sel or just regular table salt?

Fleur de sel is a particular type of sea salt. Just like “normal” sea salt, it is obtained by the evaporation of sea water in large ponds. Fleur de sel crystals, however, develop only on very hot and windless days. They form a thin layer on top of the brine, which must then be harvested quickly by hand. Its limited availabilty as well as the production efforts account for the high price of fleur de sel. The question remains whether it is worth it.

Table salt is much cheaper. It is usually made from rock salt in a largely industrialized process. After mining, the salt is purified and recrystallized, often it is enriched with iodate.

When you look through the internet, cookbooks, or magazines, you will find all kinds of reasons why you should prefer fleur de sel. More tasty, more healthy, more I don’t know what. I find these arguments sometimes rather esoteric, I do prefer a more unemotional, scientific look at it.

First of all, why do we salt at all? Why does salt make many foods taste better? In our chemistry lessons at school, we have all learned that salt is sodium chloride. Sodium is an integral component of our body, being the most abundant cation in extracellular fluid. It is closely linked with total body water homeostasis, and it drives electrical excitation (e.g. nerve and muscle cells) as well as active transport processes (e.g. water, glucose, amino acids). We constantly lose some sodium, mainly through urine and sweat, so we have to supply our body with new sodium every single day of our life. We wouldn’t have special taste receptors for sodium, if we didn’t need that substance. We wouldn’t like it, if it wasn’t that important for us. You see that almost everything in biology can be and has to be explained from an evolutionary point of view.

We have all heard that we usually eat more sodium (salt) than we really need. This is not exactly a problem since excess sodium is eliminated by the kidneys. But this shows that our preference for salted food cannot be explained by maintenance of body sodium content alone. Instead, it is much influenced by habituation. You can test that yourself, if you want. Restrict your use of salt for one or two weeks. On the first days, you will find your meals rather flavorless. Then you will get accustomed to it and will start liking them again. The problem is that pretty much everyone around you will use more salt. This means that you won’t like what your people cook for you anymore, you will find their meals oversalted. So in the end, you will probably re-adapt to the society around you and will return to your prior, more excessive use of salt.

Now that we know why we like the taste of salt, let’s have a closer look whether different types of salt taste differently. Table salt contains about 97-99 % sodium chloride, fleur de sel about 95-97 % (of the mineral components). Fleur de sel comprises several other salts such as calcium sulfate or magnesium sulfate. By the way, it is a myth that sea salt simply resembles the ionic composition of ocean water. During the production of sea salt, the increasingly concentrated brine is moved through a series of ponds. This leads to changes in its composition. Calcium carbonate, for example, is the first salt which crystallizes. By moving the brine to the next pond, the calcium carbonate is removed from the sea salt.

Still, there are 3-5 % “impurities” in fleur de sel. And they should at least theoretically be able to influence the taste. Calcium has a very distinct, slightly bitter taste, which is generated by special calcium taste receptors. However, the differences between various types of salt are quite subtle. The high level of sodium chloride just overwhelms the other components.

So, you might guess that I do not share the hype on fleur de sel. Well, that isn’t true either. If you look at my pictures of the monkfish wrapped in prosciutto, you can clearly recognize flakes of fleur de sel on the fish. I do think that there are situations in which fleur de sel is indeed superior. But these are few.

Your pasta for sure does not care which type of salt you add to the water. Just use 10 g salt per 1 l water per 100 g dry pasta and the result will be good. Even if you take the most cheapest table salt available (as I do). I am pretty sure that nobody will ever taste the difference. The same applies to any other food when you add the salt at the very beginning so that it dissolves completely.

However, in some cases I want to add a pinch of “raw salt” to a meal just before serving it. I think that the basic salting should always be done during the early steps of preparation. You want the ingredients to take up the salt deeply, instead of being salted only on the surface. This process requires some time. However, superimposing some fleur de sel to properly seasoned food, can sometimes make a good dish a perfect one. Simply because we are accustomed to like the taste of sodium.

But be careful. You will bite on “raw salt”, as I call it. Table salt has rather small, but very dense crystals. They are usually covered by anti-caking agents such as sodium hexacyanoferrate (E 535). Fleur de sel has greater crystals, but these have more of a flaky shape and contain more moisture (about 10 % per weight). This is why fleur de sel crystals have an appealing crunchy mouthfeel, while table salt crystals seem displeasingly hard.

Furthermore, fleur de sel tastes less salty then table salt. This is very important since I add it to properly salted food as I told you. While fleur de sel in this case just slightly enhances the taste, table salt would be too much. Some consider the non-sodium mineral components of fleur de sel to be responsible for the lesser saltiness. I do not believe in that theory. I think that one reason might be the higher moisture of fleur de sel compared to table salt. This means that 1 g of fleur de sel contains less sodium than 1 g of table salt, since the mineral components are “diluted” by water. Another reason might be that the larger crystals of fleur de sel are less densely packed than the smaller crystals of table salt, i.e. there is more air between them. 1 tablespoon of fleur de sel weighs less than 1 tablespoon of table salt. Taking these two arguments together, it is much easier to oversalt with table salt than with fleur de sel. A third reason for the lesser saltiness might be different dissolving kinetics.

My conclusion is that I have two kinds of salts in my kitchen pantry. Table salt is my all-purpose salt. You could just as well use coarse cooking salt (“kosher salt”, a term which does not exist in German language), fine or coarse sea salt, refined or untreated, or even fleur de sel. It simply does not make any difference, so I’m up for the cheap table salt. However, for those special cases when I salt at the end, I only use fleur de sel. It’s worth the price, especially as an expensive package of fleur de sel lasts rather long.


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