When a wine is salty, and why it shouldn’t be

Salty is not a common wine descriptor. That it’s also not a positive one probably goes without saying. As a consumer, it’s also not a fault you’re likely to fret over (I don’t think I can recall ever hearing anyone say something like “Hey, Sarah, does this wine taste salty to you?”) But the fact that wine-producing countries have (widely varying) legal maximums for sodium chloride in wine should tell you something. Salinity is a concern in dry locations when frequent irrigation increases soil salinity, which increases wine salinity, which may add one more to the list of western American winemakers’ concerns. Soil composition often doesn’t translate in the way you’d expect into grape composition; salt is, unfortunately, an exception.

An article in the American Journal of Enology and Viticulture last year mentions Australian growers’ and winemakers’ experience that grapes that taste salty may clock in under the legal sodium chloride limit and vice-versa. Law or no law, obviously no one wants “salty” to show up in their product’s tasting notes. The article reported on an effort to quantify when wine saltiness kicked in and how best to measure it. Most of the non-sodium chloride salts that show up in wine – potassium chloride is notable – register as bitter more than salty. Sodium chloride registers as salty, obviously, but also appears to convey soapy sensations. They were interested, then, both in how much salt it took for a taster to call a wine salty and in the negative impacts of defined amounts of salt on wine flavor.

Their cadre of tasters – enology students at the University of Adelaide with some specialized tasting experience – were able to first identify saltiness in Australian Shiraz and unoaked Chardonnay at .36 to 1.76 g/L with a median of .8 g/L and a lot of individual variation (values were lower for the white wine, higher for the red). The Australian legal maximum of .606 g/L, then, means that some of these folk may sometimes encounter a salty wine; the Swiss limit of .06 g/L, on the converse, seems unwarranted at least in terms of sensory concerns. The researchers also spiked the Chardonnay with several concentrations of NaCl and asked a smaller group of specially trained students to rate their sensory qualities. Those experiments confirmed that at .5 and 1 g/L, added salt dampened perceptions of fruit and added a salty flavor and soapy mouthfeel.

To the Australian researchers, the utility of their findings was in recommending that Australian growers could probably rely on their (quite possibly a bit more sensitive than average) taste perceptions to gauge grape saltiness in the field, in terms of acceptability for the Australian market, but not for meeting more stringent international guidelines. They didn’t comment on the implications of their findings for the reasonableness of those guidelines, though perhaps they go without saying. It does seem plausible that saltiness perception thresholds might vary among people of different nations accustomed to different diets, though this study’s Australian-based results were about on par with previous studies including a few conducted in Japan.

One other interesting implication, for household use. Obsessive molecular gastronomist Nathan Myrhvold has recommended that people try salting their wine as they would salt any other food. This is the same gentleman who suggests that a blender is an efficient tool for oxygenating wine, a more aggressive version of “letting it breathe” in a decanter. Myrhvold suggests a tiny pinch per glass. If one teaspoon of salt weighs about six grams, then 1/10th teaspoon per liter of wine amounts to the Australian limit of .6 g/L. A standard glass of wine is about 150mL. In other words, any realistic pinch will send your glass over the technically established edge. But it’s worth noting that Myrhvold is recommending this as a tactic to make a wine taste more savory.

I tried this with an exceptionally ordinary glass of Australian shiraz. The salt did, indeed, make the wine taste more savory. Frankly, that was neither difficult nor especially unwelcome for something that started off as a bit of a fruit bomb. But – and keep in mind that I was not tasting blind – the potential for that to be a benefit was outweighed by the kind of soapiness you get from having added a bit too much baking soda to your biscuits. In this wine, where the fruit was pretty much what it had going for it, I wouldn’t do it again, but I’m interested to see what happens with the next glass of reasonably lively Chardonnay I come across.

For producers in California, Washington, and other devastatingly dry locales, unfortunately, adding salt isn’t going to be that kind of easy option.