# Do all salts taste salty?

Recently, I am learning the production of soluble and insoluble salts. My friend and I have done this experiment at the school lab.

We wanted to taste them to see whether they are salty are not. The teacher luckily stopped us from doing that.

So without tasting them, I would really like to know whether all salts are salty.

• A very interesting case is lead(II) acetate, as well as some other lead salts. Nov 17 '14 at 12:18
• Old mantra from the folks trying to make Salt Substitutes: "There seems to be only two chemicals that taste salty to human beings, and one of them is poisonous." I believe that the poisonous one is Potassium Chloride. ... Hmm, according to Wikipedia, KCl is bitter and mildly salty, and only poisonous at high doses... Nov 17 '14 at 18:06
• Another salt which can be bought in some specialist bakery stores is Hartshorn, also known as ammonium bicarbonate. I've tasted ammonium carbonate before, and it has a sort of bitter, watery/salty taste (I know that doesn't make much sense, but I'm not sure how else to describe it). Nov 18 '14 at 14:10
• @RBarryYoung It is not KCl, it is LiCl. KCl is has no salt taste and you can find it in table salts substitutes. Please don't call it poisonous.
– Greg
Jan 5 '15 at 17:28
• @Greg Ah yes, thanks. Lithium Chloride does make more sense. KCl's status was already clarified in the same comment above. Jan 5 '15 at 17:43

No. There are sweet, bitter, and various other salts. (Likely, there are tasteless salts too). Pure salty taste is as far as I know exclusive for table salt, though I wouldn't bet on it.

Lead and Beryllium salts are said to be sweet, though toxic. Epsom salt, $\ce{MgSO4}$, is bitter. $\ce{CuSO4}$ has an incomprehensible, persistent metallic taste. (Based on personal experience. Copper salts are slightly toxic, but not extremely, so I survived with no consequences.)

Salts with hydrolysing cation (various alums) are acidic in addition to other notes.

• It seems you are dared to try them although they are toxic. Nov 17 '14 at 14:36
• @Simon-Nail-It This was a good lesson why it is necessary to wash you hands after work in a lab and before you eat. Nov 17 '14 at 15:38
• Actually, the chloride salts do lean to a salty taste, especially when a "lightweight" cation (Periods 3-4, including Na) is used. Calcium chloride is an additive to pickle brine, used to give a salty taste without increasing sodium content. Potassium chloride is a similar "salt substitute" in small doses, as is magnesium chloride (which can be a danger to wildlife when using it as a road de-icing agent, specifically because it tastes salty but becomes toxic more quickly than table salt). The "flyweight" alkalis, lithium and beryllium, are quite toxic in any quantity you could taste. Nov 18 '14 at 1:40
• Soap is a salt. May 17 '15 at 0:06
• Salty liquorice (salmiak) is pretty salty, but it contains ammonium chloride, not table salt. Sep 16 '15 at 19:16

Saltiness is perceived when alkali metal enter taste buds.

From wikipedia:

Saltiness is a taste produced primarily by the presence of sodium ions. Other ions of the alkali metals group also taste salty, but the further from sodium the less salty the sensation is. The size of lithium and potassium ions most closely resemble those of sodium and thus the saltiness is most similar. In contrast rubidium and cesium ions are far larger so their salty taste differs accordingly.[citation needed] The saltiness of substances is rated relative to sodium chloride (NaCl), which has an index of 1. Potassium, as potassium chloride - KCl, is the principal ingredient in salt substitutes, and has a saltiness index of 0.6. Other monovalent cations, e.g. ammonium, NH4+, and divalent cations of the alkali earth metal group of the periodic table, e.g. calcium, Ca2+, ions generally elicit a bitter rather than a salty taste even though they, too, can pass directly through ion channels in the tongue, generating an action potential.

• Ammonium chloride is used as a food flavoring in salty liquorice, which is quite popular here in northern Europe. The pure stuff has a very intense and distinctive, vaguely bitter flavor, that's hard to describe to someone who hasn't tasted it; it's a bit like trying to describe the taste of table salt as something other than "salty". Products flavored with it do, of course, usually also have sugar, salt and other flavorings, often including liquorice root, that blend with the taste. Nov 17 '14 at 16:32
• When you can't be bothered to write your own answer and instead just copy/paste the relevant section of wikipedia, at least put in the minimal effort needed to remove the [citation needed], or include the links, or at the very least hit enter once to preserve the paragraph breaks and make it a little easier to read. That will make it easier for you to argue that it "takes time to research an article". Nov 20 '14 at 4:35
• Well, believe it you must check this article @terdon I have edited it little bit according to what I think was needed. Obviously the [citiation needed] I once thought to remove but I didn't want to convey any wrong knowledge to my fellows who are reading it and letting them know that you don't have a good source for it. A wikipedia article would definitely have some links like : [1] linking to their reference which were indeed deleted. Nov 20 '14 at 17:02

permeakra is quite right with his counterexamples of salts that don't taste purely salty, but I'd like to expand on why. We haven't fully identified and elucidated the receptors involved in taste, but they can be broadly classed into tastes people are familiar with: salty, sweet, sour, bitter, and umami.

Salty and sour receptors are both known to be mostly dominated by ion channels, where salty receptors allow small cations to pass and sour receptors are sensitive to pH in a similar fashion. The other receptors are g-protein coupled receptors. The trick with taste (and smell, for that matter) is that there is not a single receptor type for each possible chemical one can taste, i.e. there's not a receptor entirely selective towards $\ce{Na+}$. The way it works is that there are many types of taste receptors that are somewhat selective to specific classes of molecules and a given molecule may induce a response in many different receptors. The brain takes all the data from all these receptors; combines them; integrates information from the nose, eyes, ears, tactile nerves in the mouth, etc.; and then produces the sensation of taste.

Thus, though both $\ce{Na+}$ and $\ce{K+}$ will stimulate some of the same saltiness receptors, they also stimulate other receptors and in different amounts, making them taste different. In general, small cations can stimulate the ion channel receptors for saltiness, so many salts do taste salty to a certain extent, but many also stimulate other receptors. Because what we perceive as taste comes from the interaction of all these different receptors (as well as other senses), one salt may taste very salty and another quite bitter, despite both activating saltiness receptors; the responses are not independent (which is why it's possible to mask overly salty soup or whatever by adding sugar).

The short answer is no, as suggested in the various comments. Not being a biologist I cannot give any underlying theory to explain this, but from personal and reported tasting I can give some examples: Copper sulphate, iron(II) sulphate, aluminium sulphate among others are very bitter. One you could try yourself would be sodium carbonate (washing soda) or sodium bicarbonate (baking soda). Interestingly Lead acetate as mentioned in one of the comments has a sweet taste which makes it particularly dangerous due to its toxicity. Even potassium chloride (used as a substitute for salt to reduce sodium intake) tastes quite different.

• Sodium bicarbonate does taste salty, due to the presence of sodium ions. Please don't try tasting sodium carbonate, at least not as anything but a very dilute solution -- at high concentrations, it's strongly caustic. Nov 17 '14 at 16:23
• In response to the above comment, I would first like to point out that tasting is very different from eating or drinking. I have personally tasted sodium carbonate and while it is certainly alkaline I suffered no ill effects apart from the very unpleasant soapy taste. As to sodium bicarbonate this is quite harmless and I would suggest that its taste bears little similarity to salt. Nov 17 '14 at 19:35
• I actually went and tasted a pinch of baking soda before posting that comment, and it sure does taste salty to me. It takes a second or two to come out, but that sodium flavor is definitely there. (As for sodium carbonate, you may be right. All I know is that I for sure wouldn't want to put anything that alkaline in my mouth, not even briefly.) Nov 17 '14 at 19:45

As mentioned, while not all salts taste salty, many do, and not just salts with sodium ions. If you want to try another edible salt, try to get ahold of ammonium chloride, which is used (both as a powder and otherwise) in sweets in the Nordic countries, the Netherlands and Germany. Its taste can definitely be described as salty, but not the same kind of salty as sodium chloride.

• In my opinion, the taste of ammonium chloride is due to a combination of saltiness plus an element of umami. Nov 21 '14 at 9:45

Ionic forms of some organic compounds that you will perfectly know, which can also be considered salts, have sweet taste, like sodium saccharin or sodium cyclamate, which are used as "artificial" sweeteners. The latter is considered to be about 50 times sweeter than sugar itself.